This study inquired the adsorption ability of Terminalia catappa, locally known as talisay, leaves to remove hexavalent chromium in aqueous solutions. The investigatory project placed 3rd in the 2015 Regional Science Fair held by Department of Education Region 7.

1. i
REMOVAL OF HEXAVALENT CHROMIUM IN
AQUEOUS SOLUTIONS THROUGH TALISAY
(TERMINALIA CATAPPA) LEAVES
AN INVESTIGATORY PROJECT
conducted representing
Science and Technology Education Center - Science and Technology High School
Basak, Lapu-Lapu City
PHYSICAL SCIENCE CATEGORY
INDIVIDUAL
REINA MARIZ P. BAGUIO
IP Researcher
MRS. MARIA FE G. DECATORIA
IP Adviser
November 2016

2. ii
Abstract
Terminalia catappa, locally known as talisay, remains as abundance in the Philippines. Thus,
the researcher decided to use as an adsorbent of hexavalent chromium in aqueous solutions.
Chromium has beendetected in factory sewage along with heavy metals, one of the main causes of
water pollution. This study aimed to determine the adsorption ability of talisayfor removal of
hexavalent chromium in aqueous solutions. Batch experiments were carried out in solutions
prepared by the researcher compromising of potassium dichromate and distilled water. The
experimental solutions were tested under spectrophotometry in between time intervals.
There were two experiments done by the researcher – to test the effect of varying adsorbent
dose on constant concentration of chromium content and to test the effect of a constant adsorbent
dose on carrying chromium concentration. Test results showed that after the treatment there was
100% removal of the chromium content in the aqueous solutions. The metal uptake was also
calculated to know how much milligrams of chromium content in aqueous solutions are adsorbed
by a gram of the adsorbent.
The talisayproved to be an effective adsorbent due to its characteristics - porosity and surface
area. There is a significant difference between the pre-test and posttest results in the experiments.
Therefore, the researcher recommends to test talisayon other heavy metals as well, particularly
those commonly found in factory wastewaters to minimize the amount of water contaminationdue
the heavy metals. Application of this study may include the making of a filter system connected
directly on a factory wastewater sewage system so water that would flow back on the environment
would be clean and not contaminated with hexavalent chromium which contribute to diseases in
humans.

3. iii
Acknowledgement
For the success of this study, the researcher would like to formally express her gratitude to the
persons who made this study possible with their support. The researcher’s gratitude for assistancen
is rendered to the following: Mrs. Maria Fe G. Decatoria, researcher’ IP adviser, for her
suggestions and guidance in the making of the study; Dr. Bryant C. Acar, researcher’ IP
consultant, for his valuable advises on the study and for correcting the misconceptions of the
researcher in the making of the study; Mrs. Angelita D. Pagobo, principal of Science and
Technology Education Center, for her full support and encouragement; Mrs. Kristie B. Reyes,
head chemist of the USC Water Laboratory for giving us permission to use the laboratory for the
conduct of the experiments and the completion of the study and giving further consultations about
the study; Ms. Nikki Marie Marquez, chemist at the USC Water Lab for assisting the researcher
for the use of the laboratory and testing the samples provided by the researcher; Department of
Science and Technology - Region 7 Library and Engineers for giving us free consultation and
advices about the application of the study to the researcher; Department of Agriculture for the
verification of the plant Terminalia catappa samples; The researcher’s parents, Mr. and Mrs.
Rogelio B. Baguio for their unending love and support - morally and financially to the researcher
in the making of the study, for encouraging them in times of despair, and for giving them the love
to carry on with the study; Above all, the Lord God Almighty, whom the researcher are greatly
grateful for giving them the knowledge and wisdom needed to do the study. There are no words to
express how grateful the researcher for His gift of life, strength, courage, protection, and hope
throughout the making of the study. To those people the researcher may have forgotten to
acknowledge, they would like to express their gratitude for their help and support.

4. iv
Table of Contents
Abstract.............................................................................................................................................ii
Acknowledgement.............................................................................................................................iii
Table of Contents ..............................................................................................................................iv
CHAPTER I.......................................................................................................................................1
THE PROBLEM AND ITS SCOPE.....................................................................................................1
Rationale of the Study .................................................................................................................1
Review of Related Literature........................................................................................................4
Statement of the Problem........................................................................................................... 15
Assumptions/Hypotheses........................................................................................................... 17
Significance of the Study ........................................................................................................... 18
Scopes and Limitations .............................................................................................................. 20
CHAPTER II....................................................................................................................................21
RESEARCH METHODOLOGY.......................................................................................................21
Research Design........................................................................................................................ 21
Research Environment............................................................................................................... 21
Materials and Methodology........................................................................................................22
Definition of Terms ................................................................................................................... 27
CHAPTER III..................................................................................................................................29
RESULTS AND DISCUSSION ........................................................................................................29
Findings and Analysis of Data....................................................................................................29
Summary of Findings ................................................................................................................ 41
Conclusions .............................................................................................................................. 43
Recommendations ..................................................................................................................... 44
REFERENCES.................................................................................................................................45
APPENDICES.................................................................................................................................52

5. 1
CHAPTER I
THE PROBLEM AND ITS SCOPE
Rationale of the Study
Chromium (Cr) is classified as one of the known heaviest metals. In its solid form, it is
known as a lustrous, brittle, hard metal. Its color is silver-gray and it can be highly polished.
Chromium main uses are in alloys such as stainless steel, in chrome plating and in metal
ceramics. Chromium plating was once widely used to give steel a polished silvery mirror
coating. Chromium is used in metallurgy to impart corrosion resistance and a shiny finish; as
dyes and paints, its salts color glass an emerald green and it is used to produce synthetic rubies;
as a catalyst in dyeing and in the tanning of leather; to make molds for the firing of bricks.
This research uses chromium in its 6th oxidation state, which is Hexavalent chromium
(chromium(VI), Cr(VI)). Cr(VI) refers to chemical compounds that contain the element
chromium in the +6 oxidation state. Virtually all chromium ore is processed via hexavalent
chromium, specifically the salt sodium dichromate. Approximately 136,000 tons (300,000,000
lb) of hexavalent chromium were produced in 1985(Weinheim, 2005). Cr(VI) is used for chrome
plating and the production of stainless steel as well as leather tanning, wood preservation, textile
dyes and pigments.
However, it is a heavy metal. Cr(VI) is a known human carcinogen when it is inhaled, and
can pose a serious health risk to workers in industries where it is commonly used. Although the
potential health risk of Cr(VI) in drinking water is a growing concern in many communities and
at the national level, there is not yet enough scientific evidence to confirm the actual risk or to
determine at what level of contamination it occurs.

6. 2
Water pollution is the contamination of water bodies (e.g. lakes, rivers, oceans, aquifers
and groundwater). This form of environmental degradation occurs when pollutants are directly or
indirectly discharged into water bodies without adequate treatment to remove harmful
compounds. One of the main factors of water pollution is sewage or waste water that comes from
industrial factories. These factories release water that has been exposed to harmful chemicals.
Most factories don’t have their own waste water treatment facilities and use the region’s,
or just dump it into fresh water bodies that are often where drinking water originate. However,
this poses a problem, because the waste water treatment facilities prioritize water to be consumed
by the people. In some situations, toxins have been detected in tap water at residences. An
example of this was the 2015 Hong Kong heavy metal in drinking water incidents. Samples of
potable water in Hong Kong were found to contain excessive levels of heavy metals including
lead, nickel and cadmium in 2015. Such discoveries of contamination caused widespread crisis
within the city. Cr (VI) is widely known to have been contaminating water from all around the
world.
Terminalia Catappa, or as the locals would prefer to call it, talisay, is one of the most
commonly found tree in Cebu, let alone the school of the researcher. A larger surface area will
enhance the biosorption efficiency of the biosorbent (Lim et al, 2014). Most leaves are broad and
so have a large surface area allowing them to absorb more light (“BBC”, 2014). These properties
of the talisayleaves make adsorption in hexavalent chromium possible and efficient.They are a
member of the leadwood tree family, Combretaceae, that grows mainly in the tropical regions of
Asia, Africa, and Australia (Paull and Oudhia, 2008). The leaves contain agents for
chemo-prevention of cancer and probably have anticarciogenic potential. They also have an
anticlastogenic effect (a process which causes breaks in chromosomes) due to their antioxidant
properties. Ethanol extracts of the leaves shown potential in the treatment of sickle cell disorders.

7. 3

8. 4
Review of Related Literature
Profile of talisayLeaves. Terminalia catappa, the botanical name of talisaytree, is a member
of the family Combretaceae. Terminalia catappa L. is known for its nutritional fruit and
possesses medicinal benefits as well. The tree grows to a height of 35 m with an upright,
symmetrical crown and horizontal branches. Its branches are characteristically arranged in tiers.
The leaves are large, 15-25 cm long and 10-14 cm broad, ovoid, glossy dark green, and leathery.
The trees are monoecious, with distinct male and female flowers on the same tree. Both are 1 cm
in diameter, white to greenish, and inconspicuous with no petals. The fruit is a drupe 5-7 cm long
and 3-5.5 cm broad, green at first, then yellow, and finally red when ripe, containing a single
seed. The seed within the fruit is edible when fully ripe. A larger surface area will enhance the
biosorption efficiency of the biosorbent (Lim et al, 2014). Most leaves are broad and so have a
large surface area allowing them to absorb more light (“BBC”, 2014). These properties of the
talisayleaves make adsorption in hexavalent chromium possible and efficient.
Harmful microorganisms are the agents for many diseases and deaths. Many medicines
are available but have some harmful side effects. To overcome this problem, many natural
sources are available.
The chloroform as well as methanolic extracts show good antimicrobial activity against
Gram-positive and Gram-negative microorganisms. The chloroform root extract of T. catappa
shows antimicrobial activity against Escherichia coli and Staphylococcus aureus while petroleum
root ether extract of T. catappa is devoid of antimicrobial activity. The methanolic root extract of
T. catappa exhibits minimal inhibition concentration (MIC) of 0.065 mg/ml against Escherichia
coli and the chloroform extract exhibits MIC of 0.4 mg/ml against Staphylococcus aureus.

9. 5
The aqueous and methanolic extracts of the leaves of T. catappa show different degrees
of activity against Pseudomonas aeruginosa, Pseudomonas testosteroni, Pseudomonas
pseudoalcaligenes, Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus
subflava, Proteus mirabilis, Proteus vulgaris, Proteus morganii, Bacillus cereus, Bacillus subtilis,
Bacillus megaterium, Citrobacter freundii, Micrococcus flavus, Alcaligenes faecalis,
Enterobacter aerogenes, Salmonella typhimurium, Klebsiella pneumoniae, Escherichia coli,
Streptococcus faecalis, Streptococcus cremoris, Streptococcus agalactiae, and Candida tropicalis.
The methanolic extract is significantly more efficient than the aqueous extract in inhibiting the
investigated microbial strains. Shikhamandloi et al. found that the methanolic extract shows
antifungal activity against Curvularia lunata, Aspergillus niger, Penicillium chrysogenum, and
Trichophyton tonsurans (Anand, A. V., Divya, N., & Kotti, P. P. , 2015).
Taganna et al. found that the leaves of T. catappa are rich in tannin components and are
able to inhibit certain phenotypic expression of quorum sensing (QS) in some test strains.
Akharaiyi et al. conducted the work on antibacterial activity of T. catappa. Leaves in different
stages are extracted by using water and are used against various harmful microorganisms. The
results show that T. catappa leaves have the capacity to be active against various organisms.
(Pharmacogn Rev, 2015).
Biosorption. Biosorption is a physiochemical process that occurs naturally in certain
biomass which allows it to passively concentrate and bind contaminants onto its cellular structure
(Volesky, 1990). It is a process which represents a biotechnological innovation as well as cost
effective excellent tool for removing heavy metals from aqueous solutions (Ahalya, 2003). It is
essential to realize that the metal is only “removed” from solution when it is appropriately
immobilized. The procedure of metal removal from aqueous solutions often leads to effective

10. 6
metal concentration (Volesky and Holan, 1990). Since biosorption is determined byequilibrium, it
is largely influenced by pH, the concentration of biomass and the interaction between different
metallic ions (Ahalya, 2003). Some other plants, including B.juncea and also some yeasts, employ
molecules called phytochelatins, small peptides that bind metals in forms that are less toxic to the
plant (Mofia, 1995).
The most widely used adsorbent in the industry is activated carbon. This is also known as
activated charcoal. It is charcoal that has been treated with oxygen to open up millions of tiny
pores between the carbon atoms.
Like most things, biosorption has it positives and negatives. Here are some:
• Cheap: the cost of the adsorbent is low since they often are made from
abundant or waste material.
• High uptake capacity: they have the ability to adsorb high quantity of
Heavy metals.
• Metal selective: the metal sorbing performance of different types of
biomass can be more or less selective on different metals.
• No sludge generation: no secondary problems with sludge occur with
biosorption, as is the case with many other techniques, for example, precipitation.
• Metal recovery possible: In case of metals, it can be recovered after being
sorbed from the solution.
• Competitive performance: biosorption is capable of a performance
comparable to the most similar technique, ion exchange treatment (Igwe, J. C.,
Abia, A.A., 2006).

11. 7
Here is a list of its disadvantages:
• Early saturation i.e. when metal interactive sites are occupied, metal
desorption is necessary prior to further use.
• The potential for biological process improvement (e.g. through genetic
engineering of cells) is limited because cells are not metabolizing (P.R.O
Edogbanya , O.J Ocholi and Y. Apeji, 2013).
Heavy metals such as chromium are essential for normal plant growth and development
since they are constituents of many enzymes and other proteins. However, elevated
concentrations of both essential and non‐ essential heavy metals in the soil can lead to toxicity
symptoms and the inhibition of growth of most plants. The toxicity symptoms seen in the
presence of excessive amounts of heavy metals may be due to a range of interactions at the
cellular/molecular level. Toxicity may result from the binding of metals to sulphydryl groups in
proteins, leading to an inhibition of activity or disruption of structure, or from the displacing of an
essential element resulting in deficiency effects (Van Assche and Clijsters, 1990).
Heavy metals are introduced into water bodies mainly by Industrial, agricultural, mining
and many other activities carried out by man. This is a major issue of concern due to the toxic
nature of these heavy metals, even in very minute quantities. Many conventional materials such as
commercial activated carbon have since being used in the removal of these heavy metals, mainly
by the process of adsorption. But the use of these materials is usually expensive and involves a
number of technicalities (P.R.O Edogbanya , O.J Ocholi and Y. Apeji, 2013).
The process of biosorption is mainly due to high affinity of the sorbent for the sorbate. The
sorbate is attracted and removed by various mechanisms. The process continues until equilibrium
is established between the amount of sorbate bound to the sorbent and the portion remaining in the

12. 8
solution. The degree of sorbent affinity for the sorbate determines its distribution between the solid
phase and liquid phase (Das, N., Vimala, R.,Karthika, P, 2008). For agricultural by-products, the
mode of sorption can be attributed to two main terms; intrinsic adsorption and coulombic
interaction. The coulombic term results from the electrostatic energy of interactions between the
adsorbents and adsorbates. The charges on substrates as well as softness or hardness of charge on
both sides are mostly responsible for the intensity of the interaction. Coulombic interaction can be
observed from the adsorption of cationic species versus anionic species on adsorbents (Gang S.,
1998).. The intrinsic adsorption of the materials is determined by their surface areas, which can be
observed by the effect of different sizes of adsorbent on adsorption capacity (Igwe, J. C., Abia,
A.A., 2006).
Aggregation. Particle agglomeration or refers to formation of assemblages in a suspension
and represents a mechanism leading to destabilization of colloidal systems. During this process,
particles dispersed in the liquid phase stick to eachother, and spontaneously form irregular particle
clusters, flocs, or aggregates. This phenomenon is also referred to as coagulation or flocculation
and such a suspension is also called unstable. Particle aggregation can be induced by adding salts
or another chemical referred to as coagulant or flocculant (M. Elimelech, J. Gregory, X. Jia, R.
Williams,1998). In water treatment, treatment of municipal waste water normally includes a phase
where fine solid particles are removed. This separation is achieved by addition of a flocculating or
coagulating agent, which induce the aggregation of the suspended solids. The aggregates are
normally separated by sedimentation, leading to sewage sludge. Commonly used flocculating
agents in water treatment include multivalent metal ions (e.g., Fe3+ or Al3+), polyelectrolytes, or
both.

13. 9
Flocculation, in the field of chemistry, is a process wherein colloids come out of
suspension in the form of floc or flake; either spontaneously or due to the addition of a clarifying
agent. The action differs from precipitation in that, prior to flocculation, colloids are merely
suspended in a liquid and not actually dissolved in a solution. In the flocculated system, there is no
formation of a cake, since all the flocs are in the suspension.
In colloid chemistry, flocculation refers to the process by which fine particulates are
caused to clump together into a floc. The floc may then float to the top of the liquid (creaming),
settle to the bottom of the liquid (sedimentation), or be readily filtered from the liquid.
Flocculationbehavior of soil colloids is closely related to freshwater quality. High dispersibility of
soil colloids not only directly causes turbidity of the surrounding water but it also induces
eutrophication due to the adsorption of nutritional substances in rivers and lakes.
Meanwhile in water treatment, Flocculation and sedimentation are widely employed in the
purification of drinking water as well as in sewage treatment, storm-water treatment and treatment
of industrial wastewater streams. Typical treatment processes consist of grates, coagulation,
flocculation, sedimentation, granular filtration and disinfection.
List of RelatedStudies
Related Study 1: Removal of Cr(VI) from Aqueous Solutions Using Powder of Potato
Peelings as a Low Cost Sorbent(Department of Chemical Engineering, National University of
Science and Technology, Bulawayo, Zimbabwe, 2014). Potato peels which are a low cost,
renewable agroindustry by-product were used for the removal of hexavalent chromium from
aqueous effluents. Batch experiments were carried out with an artificial effluent comprising of
potassium dichromate in deionized water. The effects of the initial hexavalent chromium
concentration, dose of adsorbent, and removal kinetics were explored. An adsorbent dosage of

14. 10
4 g/L was effective in complete removal of the metal ion, at pH 2.5, in 48 minutes. The kinetic
process of Cr(VI) adsorption onto potato peel powder was tested by applying pseudo-first-order
and pseudo-second-order models as well as the Elovich kinetic equation to correlate the
experimental data and to determine the kinetic parameters. The adsorption data were correlated by
the Langmuir and Freundlich isotherms. A maximum monolayer adsorption capacity of 3.28 mg/g
was calculated using the Langmuir adsorption isotherm, suggesting a functional group limited
adsorption process. The results confirmed that potato peels are an effective adsorbent for the
removal of hexavalent chromium from effluent (Zhe-Sheng Chen, 2014).
RelatedStudy 2: Phytochelatins and Their Roles in
Heavy Metal Detoxification (Department of Genetics, University of Melbourne, Parkville,
Victoria, 3052, Australia, 2000). Plants respond to heavy metal toxicity in a variety of different
ways. Such responses include immobilization, exclusion, chelation and compartmentalization of
the metal ions, and the expression of more general stress response mechanisms such as ethylene
and stress proteins. These mechanisms have been reviewed comprehensively by Sanita di Toppi
and Gabbrielli (1999) for plants exposed to Cd, the heavy metal for which there have been
arguably the greatest number and most wide-ranging studies over many decades. Understanding
the molecular and genetic basis for these mechanisms will be an important aspect of developing
plants as agents for the phytoremediation of contaminated sites (Salt et al., 1998). One recurrent
general mechanism for heavy metal detoxification in plants and other organisms is the chelationof
the metal by a ligand and, in some cases, the subsequent compartmentalization of the ligandmetal
complex. A number of metal-binding ligands have now been recognized in plants. The roles of
several ligands have been reviewed by Rauser (1999). Extracellular chelation by organic acids,

15. 11
such as citrate and malate, is important in mechanisms of aluminum tolerance. For example,
malate efflux from root apices is stimulated by exposure to aluminum and is correlated with
aluminum tolerance in wheat (Delhaize and Ryan, 1995). Some aluminum-resistant mutants of
Arabidopsis also have increased organic acid efflux from roots (Larsen et al., 1998). Organic acids
and some amino acids, particularly His, also have roles in the chelation of metal ions both within
cells and in xylem sap (Kramer et al., 1996; Rauser, 1999). Peptide ligands include the
metallothioneins (MTs), small gene-encoded, Cys-richpolypeptides. Our current understanding of
the functions and expression of MTs in plants, particularly Arabidopsis, have been reviewed
elsewhere (Fordham-Skelton et al., 1998; Rauser, 1999). In contrast, the phytochelatins (PCs), the
subject of this Update, are enzymatically synthesized Cys-richpeptides. The most recent review of
PC structure, biosynthesis, and function in this journal was by Rauser (1995). Other more recent
reviews are by Zenk (1996) and Rauser (1999). Recent advances inour understanding of aspects of
PC biosynthesis and function are derived predominantly from molecular genetic approaches using
model organisms (Christopher S. Cobbett, 2000).
Related Study 3: Biosorption of Heavy Metals(Department of Chemical Engineering,
McGill University, 3480 University Street, Montreal, Canada H3A 2A7, and B. V. Sorbex, Inc.,
Montreal, Canada, 1995). Only within the past decade has the potential of metal biosorption by
biomass materials been well established. For economic reasons, of particular interest are abundant
biomass types generated as a waste byproduct of large-scale industrial fermentations or certain
metal-binding algae found in large quantities in the sea. These biomass types serve as a basis for
newly developed metal biosorption processes foreseen particularly as a very competitive means
for the detoxification of metal-bearing industrial effluents. The assessment of the metal-binding

16. 12
capacity of some new adsorbents is discussed. Lead and cadmium, for instance, have been
effectively removed from very dilute solutions by the dried biomass of some ubiquitous species of
brown marine algae such as Ascophyllum and Sargassum, which accumulate more than 30% of
biomass dry weight in the metal. Mycelia of the industrial steroidtransforming fungi Rhizopus and
Absidia are excellent adsorbents for lead, cadmium, copper, zinc, and uranium and also bind other
heavy metals up to 25% of the biomass dry weight. Biosorption isotherm curves, derived from
equilibrium batch sorption experiments, are used in the evaluation of metal uptake by different
adsorbents. Further studies are focusing on the assessment of adsorbent performance in dynamic
continuous-flow sorption systems. In the course of this work, new methodologies are being
developed that are aimed at mathematical modeling of biosorption systems and their effective
optimization. Elucidation of mechanisms active in metal biosorption is essential for successful
exploitation of the phenomenon and for regeneration of adsorbent materials in multiple reuse
cycles. The complex nature of adsorbent materials makes this task particularly challenging.
Discussion focuses on the composition of marine algae polysaccharide structures, which seem
instrumental in metal uptake and binding. The state of the art in the field ofbiosorption is reviewed
in this article, with many references to recent reviews and key individual contributions (B.
Volesky and Z. R. Holant, 1995).
Related Study 4: UTILIZATION OF MANGO LEAF AS LOW-COST ADSORBENT FOR
THE REMOVAL OF CU(II) ION FROM AQUEOUS SOLUTION (Ong Pick Sheen, 2011). Heavy
metal contamination exists in aqueous waste streams of many industries suchas metal purification,
metal finishing, chemical manufacturing, mining operations, smelting, battery manufacturing, and
electroplating. (Liang et al., 2009; Issabayeva et al., 2010; Lu and Gibb, 2006). As a result of

17. 13
industrial activities and technological development, the amount of heavy metal ions discharged
into streams and rivers by industrial and municipal wastewater have been increasing incessantly
(Serencam et al., 2007). Heavy metals are member of a loosely-defined subset of elements that
exhibit metallic properties, which mainly includes the transition metals, some metalloids,
lanthanides, and actinides. Certain heavy metals such as iron, copper (Cu), zinc and manganese are
required by humans for normal biological functioning. However, heavy metals such as mercury,
lead, cadmium are toxic to organisms. Most of the health disorders are linked with specific
tendency of heavy metals to bioaccumulate in living tissues and their disruptive integration into
normal biochemical processes (Issabayeva et al., 2010). Increased use of metals and chemicals in
process industries has resulted in generation of large quantities of effluent that contains high level
of toxic heavy metals and their presence poses environmental-disposal problems due to their
non-degradable and persistence nature (Ahluwalia and Goyal, 2 2005). Table 1.1 shows the
permissible limits and health effects of various toxic heavy metals. Most heavy metals are cations,
carrying a positive charge, such as zinc and cadmium. Soil particles tend to have a variety of
charged sites on their surfaces, some positive while some negative. The negative charges of these
soil particles tend to attract and bind the positively charged metal cations, preventing them from
becoming soluble and dissolve in water. The soluble form of metals is more dangerous because it
is easily transported, hence more readily available to plants and animals. Metal behavior in the
aquatic environment is surprisingly similar to that outside a water body. Sediments at the bed of
streams, lakes and rivers exhibit the same binding characteristics as soil particles mentioned
earlier. Hence, many heavy metals tend to be sequestered at the bottom of water bodies. Yet, some
of these heavy metals will dissolve. The aquatic environment is more susceptible to the harmful
effects of heavy metal pollution. Metal ions in the environment bioaccumulate and are

18. 14
biomagnified along the food chain. There, their toxic effect is more pronounced in animals at
higher trophic levels (Ahluwalia and Goyal, 2005).
Related Study 5: Adsorption of Malachite Green (MG) on Low Cost – Adsorbent from
Aqueous Solution (Fouad F. Al-Qaim, 2011). The use of cheap adsorbent has been studied as an
alternative substitution of activated carbon for the adsorption of MG from its aqueous solution.
The low cost adsorbent Egg Shell Powdered (ESP) was successfully used for the sorption
dyes from its aqueous solution .This study investigates the potential of egg shell powder as a low
cost adsorbent for malachite green removal from its solution. The equilibrium time was 60 min.
The effect of initial concentration for MG, sorption time on dye removal, and dose of
adsorbent was studied. The equilibrium sorption isotherms have been analyzed by the linear,
Freundlich and Langmuir models. The kinetics studies were provided with Pseudo first order.

19. 15
Statement of the Problem
This study aimed to determine the biosorption ability of talisay(Terminalia catappa) for
removal of hexavalent chromium in aqueous solutions. Furthermore, the researcher sought
answers for the following subsidiary questions:
1. What is the chromium content before the treatment in the following to test the effect of
varying adsorbent dose on constant chromium concentration:
1.1 negative setup;
1.2 experimental setup 1 (10g talisay);
1.3 experimental setup 2 (20g talisay); and
1.4 experimental setup 3 (30g talisay)?
2. What is the chromium content after the treatment in the same setups in the following
time intervals:
2.1 10 minutes;
2.2 20 minutes;
2.3 30 minutes?
3. Is there a significant difference in the chromium contents before and after the treatment to
test the effect of varying adsorbent dose on constant chromium concentration?
4. What is the chromium content before the treatment in the following to test the effect of
constant adsorbent dose on varying chromium content:
1.5 experimental setup 1;

20. 16
1.6 experimental setup 2;and
1.7 experimental setup 3?
5. What is the chromium content after the treatment in the same setups in the following
time intervals:
2.4 10 minutes;
2.5 20 minutes;
2.6 30 minutes?
6. Is there a significant difference in the chromium contents before and after the treatment to
test the effect of constant adsorbent dose on varying chromium concentration?
7. What is the amount of adsorption per unit mass (metal uptake) of the talisayleaves in the
setups to test the following:
7.1 the effects of varying adsorbent dose treated on constant chromium
concentrations; and
7.2 the effects of constant adsorbent dose treated on varying chromium
concentrations?

21. 17
Assumptions/Hypotheses
1. There is no significant difference between the following:
1.1 chromium contents before and after the treatment to test the effect of constant
adsorbent dose on varying chromium concentration.
1.2 chromium contents before and after the treatment to test the effect of varying
adsorbent dose on constant chromium concentration?

22. 18
Significance of the Study
Water pollution is one of the major problems that the world is currently facing. Most of
the waste water comes from factories and most likely contains harmful and heavy metals. With
the rapid development of many industries and aerospace and atomic energy installations, wastes
containing metals are directly or indirectly being discharged into the environment causing
serious environmental pollution and even threatening human life.
Hexavalent chromium makes up a large percentage in waste water produced by certain
factories. It is can cause lung cancer, ulcers, nasal septum perforations, and damage to the
kidneys. Further, it can also cause chromium dermatitis which is chronic and difficult to treat.
Human exposure to hexavalent chromium can further encompasses impaired fertility, heritable
genetic damage and harm to unborn children.
Specifically this study benefits the following:
The Community. That through this study, they become appreciative of the abilities of T.
catappa especially in treating waste water from factories; and aware about their health and will
be knowledgeable about the contamination and will eventually teach them how to prevent and
treat contamination of water.
People Living near Bodies of water. They will benefit from this study because we’ll be
able to prevent any damages to one’s body due to the heavy metals on polluted water. They
would also be aware about the possible effects contamination and exposure to hexavalent
chromium would be avoided.
The Philippine Economy. This study paves the way to reduce the cost of water treatment
by providing alternative natural methods of treating wastewater.

23. 19
The Researcher. The making of this paper enhances their skills in research, improves their
knowledge and cultivates their interest in discovering pesticidal uses of indigenous talisayplant.
Wastewater Engineers. The findings will give them opportunity to undertake further
research and water-treating development. Futhermore, they can make an innovation to improve
and use this study.
School. This will be used as a reliable material and reference for discussion and teaching.
This is a source of knowledge for them of which they can base their future studies.
Future Researcher. This study can be used a reference for their personal studies with
regards to wastewater engineering and treatment. It will give them a background to their study.

24. 20
Scopes and Limitations
The study only focuses and investigates on the pure knowledge on the biosorption
potential of talisay leaves on removing hexavalent chromium in aqueous solutions. The study
doesn’t cover the disposal of the adsorbent after the treatment. Due to the expensive laboratory
test, the study is only limited to testing and manipulating the effects of adsorbent dosage and
intial concentration of chromium over time. Other factors that could affect the adsorption
capacity such as pH level and temperature were not manipulated instead they were constant.

25. 21
CHAPTER II
RESEARCH METHODOLOGY
ResearchDesign
The researcher used the quasi experimental method of analysis in order to reach the
investigatory objectives of the study. The researcher undertook 2 experiments to investigate the
answers to the stated subproblems. These are the two experiments tested by the researcher:
1. The Effects of Varying Adsorbent Dose (10, 20, 30 grams) Treated on Constant
Chromium Concentrations (20 ppm)
2. The Effects of Varying Chromium Concentrations (10, 20, 30 ppm) Treated with Constant
Adsorbent Dose (20 grams)
ResearchEnvironment
The collection of the talisayleaves were conducted at the school of the researcher
“Science and Technology Education Center” and at the residence of the researcher Aleya
Oliveron at Basak, Lapu-Lapu City. The preparation and shredding of the leaves were done at
the residence of researcher Christia N. Tangin at Kaimitohan, Basak, Lapu-Lapu City. The
powdered form Cr(VI) was obtained from the Chemistry Laboratory of the University of San
Carlos – Talamban Campus. The aqueous solutions of chromium was then prepared at the USC
Water Lab and at STEC Chemistry Laboratory. The chromium was dissolved at varying
concentrations. The solvent used in the solutions was distilled water.

26. 22
Materials and Methodology
Collection of Plant Material. Fresh matured leaves from talisay(T. catappa) trees at Science
and Technology Education Center were collected. Plant samples were submitted to Department
of Agriculture Region 7 for verification and certification.
Preparation of Adsorbent Material. First, the leaves were washed with distilled water to
remove all contaminants e.g. dust that could affect the further results. The leaves were then
sun-dried for 48 hours. Then, they were heated in an oven toasted at 350 degrees Fahrenheit for
20 seconds to produce char. According to (Metcalf and Eddy,1989) exposure of the char particle
to an oxidizing gas at a high temperature develops a porous structure thus creating a large
internal surface area. After cooling the leaves, it was then shredded using a blender. The
adsorbent was then stored in a container.
Hexavalent Chromium Solution Preparation. Preparations of chromium solutions vary
according to the version of method used in the study. Each preparation would be elaborated as
follows.
Experiment 1. A stock solution of 2622.5 ppm was prepared by 0.5245 g
of K2C2O7 into 0.2 L of distilled water. Experimental solutions (10ppm, 20ppm,
30ppm) were obtained from the stock solution by appropriate dilutions with
250mL of distilled water.
Experiment 2. The chromium concentration in this set-up is constant. The
constant concentration was 20ppm. This was prepared by taking 7.6 mL of the
2622.5ppm solution, then filling the flask to 1000mL.

27. 23
Treatments
Experiment 1. Effect of Varying Adsorbent Dose on Constant Cr (VI)
Concentration. This method tests if there are any significant differences in varying
adsorbent dose at constant chromium concentration which is 20 ppm. 4 setups of
200mL of 20 ppm chromium solution were prepared in separate beakers. The initial
setups were tested under spectrophotometry. The varied adsorbent doses of 10
grams, 20 grams, and 30 grams were added as treatment. The negative control setup
was the chromium solution not added with the adsorbent. 10 mL was taken from
each solution for testing under spectrophotometry. Testing was done in the interval
of 10 minutes. Refer to table 1.1 of the prepared readings sheet for each
experimental group.
Table 1.1
Experiment 1 sample table for absorbance readings
READINGS (Interval of 10 mins)
Amount of adsorbent Initial 10 mins 20 mins 30 mins
0 – negative control setup
10 grams
20 grams
30 grams

28. 24
Experiment 2. Effect of 20 grams talisayon varying Chromium concentrations.
This method tests if there is any significant difference between the setups of varying
chromium concentrations; 10 ppm, 20 ppm, 30 ppm, once treated with a constant
amount 20 grams for the adsorbent talisay. Each chromium solution of different
concentration were placed in separate beakers and were all treated with 20 grams of
the shredded adsorbent. In every 10 minutes, 10 ml of the solution was taken for
sampling and testing under spectrophotometry. This was done thrice, and testing
done with the UV-Vis Spectrophotometer. There was no negative control group set,
but the conclusions for the readings were based on the initial concentration of each
solution before treated with said adsorbent. Refer to table 3.2 of the prepared
readings sheet for each experimental group.
Table 1.2
Experiment 2 Sample Table for absorbance readings
READINGS (Interval of 10 mins)
Chromium Concentration
(in ppm)
Initial 10 mins 20 mins 30 mins
10 ppm
20 ppm
30 ppm

29. 25
Spectrophotometer Reading. The diphenyl carbazide colorimetric method was used to read
the chromium solutions. The hexavalent chromium was determined colorimetrically by reaction
with diphenyl carbazide in acid solution. A red-violet color of unknown composition was
produced in this method.
Color development and measurement. 0.25 mL (5 drops) H3PPO4 was added to the 10 mL
taken from each chromium solution set up. 0.2N H2SO4 and a pH meter were then used to adjust
the solution to pH 2.0 ± 0.5. A solution of 100-mL sample was transferred in a volumetric flask
and diluted to 100 mL and mixed afterwards. A 2.0 mL solution of diphenyl carbazide was
added and the solution was let still for 5-10 mins for full color development. An appropriate
portion of each solution was transferred to a 1-cm absorption cell and its absorbance was
measured at 540 nm. Distilled water was used for reference. The absorbance reading of the
sample was corrected by subtracting absorbance of a blank carried through the method.
Statistical Treatments. Statistical tools used for the results were the t-test. This is used to
test if the differences between the pretests and post-tests are significantly different from each
other.
Amount of Adsorption per Unit Mass of the talisayLeaves (Metal Uptake).
The quality of the sorbent material is judged according to how much sorbate it can
attract and retain in an ‘immobilized’ form. For this purpose it is customary to
determine the metal uptake (q ) by the adsorbent as the amount of sorbate bound by
the unit of solid phase (by weight, volume, etc.). The Cr(VI) uptake or the amount
of adsoprtion was calculated from mass balance and the difference between initial
and final chromium concentrations by using the formula:

30. 26
)(0
V
M
CC
q e

Where:
q - is the metal uptake
C o - is the initial Cr(VI) concentration
C e - is the final Cr(VI) concentration
M- is the mass of adsorbent or the adsorption dose
V- is the volume of the solution used
Removal Percentage. The removal percentage of chromium was calculated
using the formula:
o
e
C
CC
removalVICr
)(100
%)( 0 

Where:
Cr(VI)removal% - is the percentage of removed chromium from
the solution
C o - is the initial Cr(VI) concentration
C e - is the final Cr(VI) concentration

31. 27
Definition of Terms
To fully understand the terms used in this study, they are defined operationally as
follows:
Adsorbate. A substance adsorbed. Refers to the Chromium in this experiment.
Adsorption. Adsorption is the adhesion of molecules of gas, liquid, or dissolved solids to a
surface.
After Treatment. Refers to the state of the subject after researcher’s planned procedure was
done unto the subject.
Aqueous Solution. Any solution with water as the main solvent.
Before Treatment. Refers to the state of the subject before researcher’s planned procedure
was done unto the subject.
Control Group. Refers to a group in an experiment that does not receive treatment from the
researcher and is used as the basis on how they will measure the other subjects.
Control Set up. Refers to the set-up similar to the experimental, however, the researcher do
not alter or test any of the variables.
Experimental Group. Refers to a group in an experiment that receives treatment from the
researcher. It is compared to the control group.
Experimental Set up. Refers to the set-up which the researcher tests.

32. 28
Heavy Metal. Any metallic chemical element that has a relatively high density and is toxic
at low concentrations. Common examples of these are mercury (Hg), cadmium (Cd), Arsenic
(As), and Chromium (Cr).
Procedure. Refers to the method or treatment that the researcher expose the subject to.
Wastewater. Any water that has been affected or changed due to human activity. This
term is often used relative to sewage, however, it is classified into many categories in accordance
to where it originates.

33. 29
CHAPTER III
RESULTS AND DISCUSSION
Findings and Analysis of Data
Testing the Effect of Varying Adsorbent Dose on Constant Chromium Content
I. Chromium Content before the Treatment
The aqueous solutions were prepared by diluting potassium dichromate, a hexavalent
chromium compound in appropriate amounts of distilled water. There were a total of 4 setups in
this experiment. Hexavalent chromium was chosen as the heavy metal in this study, because it is
one of the toxic heavy metals that contaminates wastewater from factories in making alloys such
as stainless steel, in chrome plating and in metal ceramics. This heavy metal is a known human
carcinogen when it is inhaled, and can pose a serious health risk to workers in industries where it
is commonly used (IARC,1990).

34. 30
Table 2.1
Chromium Content before the Treatment
Table 2.1 shows the chromium content before the treatment of the solutions. This experiment
uses constant chromium concentration which is 19.3-19.4 ppm. Each experimental setup has a
different planned amount of adsorbent dose.
II. Chromium Content after the Treatment
The adsorbent used in this experiment was the talisay. According to Lim et al, a large
surface area enhances the adsorption efficiency of the adsorbent (2014). The porosity of the
leaves is another factor of its adsorption capability (Jhadhav, n.d.) .
The experimental setups were treated with varying adsorbent dose (10, 20, and 30 grams).
10 mL of the solutions were taken from each setup. The solutions were then tested under the
Setups
Chromium Content
(ppm)
Interpretation
Negative
Control
19.4
very high
concentration
Experimental 1
10 g talisay
19.3
very high
concentration
Experimental 2
20 g talisay
19.4
very high
concentration
Experimental 3
30 g talisay
19.3
very high
concentration

35. 31
spectrophotometer to identify the chromium content in each setup. This procedure was repeated
three times in different intervals (10, 20, and 30 minutes).
Table 2.2
Chromium Content after the Treatment
( in 10, 20, 30 minutes)
Setups
Chromium
Content (ppm)
Removal Interpretation
Negative Control 19.4 0%
very high
concentration
Experimental 1
10 g talisay
0 100% No concentration
Experimental 2
20 g talisay
0 100% No concentration
Experimental 3
30 g talisay
0 100% No concentration
Table 2.2 shows that the negative control setup had no changes in chromium content. This
was expected since no treatment was made. On experimental setups 1, 2, and 3, there was no
chromium content on the treated solutions. After the given time, the chromium content on the
experimental solutions were adsorbed by the talisay.
On the first test (after 10 minutes), the chromium content on the experimental setups were
fully removed. Hence, the chromium content after 20 and 30 minutes, the results were the same.
III. Difference of the Chromium Content Before and After the Treatment

36. 32
Using the t-test, the significance of the differences of the chromium contents before and after
the treatment was computed.
Table 2.3
Difference of the Chromium Content Before and After the Treatment
Table 2.3 shows the significance of the differences between the chromium content before
and after the treatments. With the confidence level of 95% and degree of freedom of 4, the
critical level according to the t-distribution table is 2.776. Since the t-value is 3.3625 and is
within the area of rejection, therefore it can be concluded that there is a significant difference
between chromium contents before and after the treatment in all intervals of time (10, 20, and 30
minutes).
Before Treatment After Treatment
Mean 19.033 0
Standard
Deviation
9.804 0
Standard Error of the
Mean
5.66 0
Number of setups 3 3
Computed t value 3.3625
Critical t 2.776
Decision Rejected Ho
Interpretation Significant

37. 33

38. 34
Testing the Effect of Constant Adsorbent Dose onVarying Chromium Content
IV. Chromium Content before the Treatment
This experiment was done to test the effect of constant adsorbent dose on varying chromium
content on the aqueous solutions. The aqueous solutions were prepared by diluting potassium
dichromate, a hexavalent chromium compound in appropriate amounts of distilled water. There
were a total of 3 experimental setups in this experiment. In this experiment, the constant
adsorbent dose was 20 grams of talisay. The hexavalent chromium content on each experimental
setup varied ( 10, 20, and 30 ppm).
Table 2.4
Chromium Content before the Treatment
Setups
Chromium Content
(ppm)
Interpretation
Experimental 1
9.4
Very high
concentration
Experimental 2
18.7
Very high
concentration
Experimental 3
29.0
Very high
concentration

39. 35
Table 2.4 shows chromium content before the treatment of the solutions. Each
experimental setup had different chromium contents (9.4, 18.7, and 29.0 ppm) before the
treatment on the setups.
V. Chromium Content after the Treatment
The adsorbent used in this experiment was the talisay. This experiment is similar to the
first experiment however their objectives and parameters were different. Their explanation
and reason of their adsorption capability are the same. According to Lim et al, a large
surface area enhances the adsorption efficiency of the adsorbent (2014). The porosity of the
leaves is another factor of its adsorption capability (Jhadhav, n.d.).
The experimental setups were treated with constant adsorbent dose – 20 grams. 10 mL of
the solutions were taken from each setup. The solutions were then tested under the
spectrophotometer to identify the chromium content in each setup. This procedure was
repeated three times in different intervals (10, 20, and 30 minutes).

40. 36
Table 2.5
Chromium Content after the Treatment
( in 10, 20, and 30 minutes)
Setups
Chromium
Content (ppm)
Removal Interpretation
Experimental 1
9.4 ppm
0 100% no concentration
Experimental 2
18.7 ppm
0 100% no concentration
Experimental 3
29.0 ppm
0 100% no concentration
Table 2.5 shows that there are no chromium content on all experimental setups after the
treatment of 20 grams talisay dose on all setups. After the given time, the chromium content on
the experimental solutions were adsorbed by the On the first test (after 10 minutes), the
chromium content on the experimental setups were fully removed. Hence, the chromium content
after 20 and 30 minutes, the results were the same.

41. 37
VI. Difference of the Chromium Content Before and After the Treatment
Using the t-test, the significance of the differences of the chromium contents before and after
the treatment was computed. This test seeks to determine if there is a significant difference in
having a constant adsorbent dose on varying chromium content.
Table 2.6
Difference of the Chromium Content Before and After the Treatment
Before Treatment After Treatment
Mean 19.333 0
Standard
Deviation
0.058 0
Standard Error of the
Mean
0.033 0
Number of setups 3 3
Computed t value 580
Critical t 2.776
Decision Rejected Ho
Interpretation Significant

42. 38
Table 2.6 shows the significance of the differences between the chromium content before
and after the treatment. With the confidence level of 95% and degree of freedom of 4, the critical
level according to the t-distribution table is 2.776. Since the t-value is 580 and is within the area
of rejection, therefore it can be concluded that there is a significant difference between
chromium contents before and after the treatment.

43. 39
Metal Uptake
VII. Metal Uptake on the Effects of Varying Adsorbent Dose treated on Constant
Chromium Contents
The metal uptake is the amount of adsorption per unit mass of the talisayleaves. Using the
results of the experiment on the effects of varying adsorbent dose with constant chromium
contents, the researcher was able to calculate the metal uptake.
Table 2.7
Metal Uptake on the Effects of Varying Adsorbent Dose treated on Constant Chromium
Contents
Table 2.7 shows the amount of the adsorption or the metal uptake on the set-ups with
different adsorption dose. As show on the table, the amount of adsorption decreases as the
amount of the adsorbent dose increases with a constant concentration of Cr(VI). The decrease in
the amount of adsorption with an increase in the adsorbent dose is mainly because of
unsaturation of adsorption sites through the adsorption process (Dorris et al, 2003). Another
reason may be the inter-particle interaction, such as aggregation, resulting from high adsorbent
Adsorption Dose(g) Amount of Adsorption (mg/g)
10 mins 20 mins 30 mins
0g 0 0 0
10g 0.4825 0.4825 0.4825
20g 0.2425 0.2425 0.2425
30g 0.16 0.16 0.16

44. 40
dose. Aggregation would lead to a decrease in the total surface area of the adsorbent and on an
increase in diffusional path length (Dorris et al, 2003).
VIII. Metal Uptake on the Effects of Constant Adsorbent Dose treated on Varying
Chromium Contents
The metal uptake is the amount of adsorption per unit mass of the talisayleaves. Using the
results of the experiment on the effects of varying chromium contents with constant adsorbent
dose, the researcher was able to calculate the metal uptake.
Table 2.8
Metal Uptake on the Effects of Constant Adsorbent Dose treated on Varying Chromium
Contents
Table 3.2 shows the amount of the adsorption or the metal uptake on the set-ups
with different initial concentration of Cr(VI). The amount of adsorption increased with
the increase in the initial concentration. This means that the adsorption is highly
dependent on the initial concentration of hexavalent Chromium .This is because at lower
concentration the ratio of the initial number of the chromium molecules to the available
surface area is low.
Initial
Concentration
Amount of Adsorption (mg/g)
10 mins 20 mins 30 mins
10 ppm 0.1175 0.1175 0.1175
20 ppm 0.2338 0.2338 0.2338
30 ppm 1.8125 1.8125 1.8125

45. 41
Summary of Findings
Testing the Effect of Varying Adsorbent Dose on Constant Chromium Content
I. Chromium Contents after the Treatments (10, 20, 30 min)
In 10, 20 and 30 minutes after the treatment, the chromium contents on all
experimental setups were removed. The negative control setup had very little to no changes
at all. This is because no treatment was done on this setup.
II. Difference of the Chromium Content Before and After the Treatment
There was a significant difference on the pre- and posttests of all experimental setups
as all chromium content were adsorbed and it showed no signs of desorption. The negative
control had no significant as there was little to no removal at all.
Testing the Effect of Constant Adsorbent Dose on Varying Chromium Content
III. Chromium Contents after the Treatments (10, 20, 30 min)
In 10, 20 and 30 minutes after the treatment, the chromium contents on all
experimental setups were removed and readings were constant since its first reading. There
were no signs of desorption.
IV. Difference of the Chromium Content Before and After the Treatment
There was a significant difference on the pre- and posttests of all experimental setups
as all chromium content were adsorbed and it showed no signs of desorption. The
negative control had no significant as there was little to no removal at all.

46. 42
Metal Uptake
V. Metal Uptake on the Effects of Varying Adsorbent Dose treated on
Constant Chromium Contents
The amount of adsorption is inversely proportional to the adsorbent dose. This means
that the amount of adsorption decreases as the amount of the adsorbent dose increases
with a constant concentration of Cr(VI).
VI. Metal Uptake on the Effects of Constant Adsorbent Dose treated on Varying
Chromium Contents
The amount of adsorption is directly proportional to the adsorbent dose. This means
that the amount of adsorption increases as the amount of the chromium concentration
increases with a constant concentration of Cr(VI).

47. 43
Conclusions
1. There is a significant difference between the chromium contents before and after the
treatment to test the effect of constant adsorbent dose on varying chromium
concentration.
2. There is a significant difference between the chromium contents before and after the
treatment to test the effect of varying adsorbent dose on constant chromium
concentration.
3. In the experiments, time element is not a factor contributing to the adsorption capability
of the talisay.
4. Different amount of adsorbent dose and different chromium content in the aqueous
solutions do not affect the adsorption capability of talisay.
5. The metal uptake is inversely proportional to the amount of adsorbent dose; and directly
proportional to the amount of chromium content in the solution.
Conclusively, talisay is an effective adsorbent in removing hexavalent chromium in aqueous
solutions. It can be said that talisayhas properties such as large surface and porosity to adsorb
hexavalent chromium. They are cheaper and biodegradable and can be used easily by an ordinary
man without hazardous effects.

48. 44
Recommendations
The researcher would like to recommend to future researcher the exploration of the other
different variables that can affect the adsorption such as pH level, temperature, particle size, etc.
It is also best to find a way to treat the adsorbent after the treatment and remove the chromium
from it. The talisayis also reusable once the heavy metal is removed, and it is recommended to
find a simpler way of doing so.
Replication of the experimental setups, use of positive control ( e.g. activated carbon) group
for comparison, and the use of negative control group are also highly recommended by the
researcher in further experimentations.
Lastly, the application of this research is highly recommended. Finding out a method on
how this new data about talisayas an adsorbent should be studied further and applied to help
solve pollution. Its application using a filter box recommended by the DOST, would be an
innovative and cheaper way to treat wastewater from factories.

49. 45
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56. 52
APPENDICES
Appendix A
Documentation
Preparation of the standard solution Set-ups for test the effects of Intial
concentration of Cr (VI)
Exposure of talisayleaves to high
temperature.
Dilution of solution to acquire the
needed ppm.

57. 53
Blending the talisay leaves into
shredded particles.
Talisay leaves as adsorbent.
Weighing of talisay leaves into
different adsorbent dose.
The talisay leaves dose varied 10
grams,20 grams, and 30 grams
Filtering the set-ups for the analysis
of chromium content.
The different experimental set-ups and
negative control set-ups prior to the
chromium analysis

58. 54
Appendix B
Gantt Chart
Week
Activities 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Approval of IP
Proposal
Submission of
Facility Use
Proposal
Experimentation at
USC
Verification of Plant
Sample
Retrieval of Plant
Material
Research on Related
Studies

59. 55
Appendix C
Bell Curve for t-test
Difference in the Effects of Constant Adsorbent Dose on Varying Chromium
Concentrations (10, 20, 30 minutes)
Difference in the Effects of Constant Chromium Concentrations on Varying Adsorbent
Dose (10, 20, 30 minutes)
Test t=508

60. 56
Appendix D
Metal Uptake of the Adsorbent
0
0.1
0.2
0.3
0.4
0.5
10 20 30
Amountofadsorption(mg/g)
Time(mins)
Effects of Adsorbent Dose
10g 20g 30g
Metal Uptake on the Leaves on the Experiment on testing the Effects of the Varying Adsorbent
Dose
0
0.5
1
1.5
2
10 20 30
Amountofadsorption(mg/g)
Time(mins)
Effects of Initial Concentration of Cr(VI)
10 ppm 20 ppm 30 ppm
Metal Uptake on the Leaves on the Experiment on testing the Effects of the Varying Adsorbent
Dose

61. 57
Appendix E
Summary of Budget
Product/Service Cost
USC Laboratory Test PHP 8,985.00
Distilled Water PHP 158.00
Ear Syringe PHP 20.00
Chromium Compound PHP 78.00
Masks PHP 12.00
Transportation PHP 500.00
Printing Services PHP 300.00
Total Cost PHP 10, 053.00

62. 58
Appendix F
Quantification
(Classification categorized according to researcher)
Scale Interpretation
0 None
1-5 Very Low
6-10 Low
11-15 High
16-20 Very High
21-25 Severely High
26 and above Extremely High

63. 59
Appendix G
Correlation of Pre-test and Post-test.
varying adsorbent varying chromium content
pretest talisay Cr pretest talisay Cr
0 19.4 20 9.4
10 19.3 20 18.7
20 19.4 20 29
30 19.3 0 0
0 0
0 0
protest talisay Cr protest 0 0
0 19.4 20 0
10 0 20 0
20 0 20 0
30 0
120 96.8 60 57.1
Mean 15 12.1 Mean 20 19.03333
SD 11.18034 9.3727 SD 0 8.005137
pre&post -0.34832 pre&post 0.477575 0.477575
pre -0.44721 pre 0.765264
post -0.7746 post 0