Undergraduate Theses
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Item Removal of total solids from surface water of Malihao River, Victorias, Negros Occidental using chitosan derived from green mussel (Perna viridis) shellCaligan, Jeff Tristan Z. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2018-06)Total solids are water pollutants that can either be suspended or dissolved in water. Suspended solids are those that can be filtered while those that can passed through are considered as dissolved solids. Five sampling stations were tested along Malihao River in Victorias City, Negros Occidental to determine parameters such as pH, temperature, total settleable solids (TSeS), total suspended solids (TSS), total dissolved solids (TDS), volatile suspended solids (VSS), conductivity, and salinity. Among these parameters, the focus of the study is on TSS and TDS and assess the removal efficiency of chitosan with these pollutants. The chitosan used was obtained from the shells of green mussel (Perna viridis) through deacetylation of chitin. The chitosan obtained has 73% degree of deacetylation and has characteristic peaks in the IR spectra at 3470.82 cm-1 and 1636.36 cm-1 representing the vibrating aliphatic O-H and bending N-H group, respectively. The optimum chitosan dosage was determined at 15 mg, which has removal efficiency of 83.46% and 25.48% for TSS and TDS, respectively. It also decreases the turbidity of the water based on the clarity in color. High TSS values were observed at Station 2 (Malihao Bridge) and Station 5 (Daan Banwa Wharf) with values of 125.5 and 232.0 mg/L, respectively. These values exceed the DENR Administrative Order 2016-08 for Class C waters, which is 80 mg/L. The optimum dosage was used to remove TSS and TDS at each sampling stations. TSS of all sampling stations were reduced to more that 50% of the initial value while TDS values rose to 80% and higher of the initial value. Thus, chitosan derived from green mussel shells were effective in removal of TSS but not with TDS.Item Comparative study of trace metals and common impurities of table salt produced in Leganes, Iloilo and Tibiao, AntiqueCalawag, Jerolet E. (Division of Physical Sciences and Mathematics, College of Arts and Sciences, University of the Philippines Visayas, 2000-10)Trace metals such as cadmium (Cd), chromium (Cr) and lead (Pb) as well as the common impurities in salt like magnesium (Mg), calcium (Ca), sulfate, moisture, matter insoluble in water (MIW) and matter insoluble in acid (MIA) were analyzed using spectrophotometric (Flame Atomic Absorption &UV-vis Spectrophotometers) and gravimetric methods. Results showed that percentage concentrations of magnesium and calcium were significantly higher in sample A (Tibiao table salt) than in sample B (Leganes table salt) at 1- percent level of confidence. The percentage concentrations of MIW, MIA, moisture and sulfate were significantly higher in sample B than in sample A. Results of Uv-vis absorption spectroscopy indicated that both chromium and cadmium were absent in both samples while the lead concentrations in samples A and B were 10.9190 and 11.4831 ppm respectively. At 5% level of probability, the lead concentrations of both samples did not differ from each other. Using another technique of analyzing trace metals, the flame atomic absorption spectroscopy based on flame atomization, different results were obtained. Lead concentration in samples A and B were 6.4874 and 9.4977-ppm salt respectively. At 5 % level of probability, sample B had higher lead concentration than in sample A. The lead concentrations in both samples were all higher than 0.015 ppm, the allowable maximum limit of lead in water, or any drinks. The over-all results showed that sample B had higher contaminants than in sample A.Item Sediment organic matter, nitrogen, and phosphorus of four tivers in Miagao, IloiloCahilig, Guen Gian D. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2019-06)The four rivers of Miagao are examples of aquatic areas where sediment pollution can be related and mostly caused by anthropogenic and non-point sources. The four rivers of Miagao, namely Bacauan, Naulid, Oyungan and Tumagbok rivers, were assessed and observed to have low levels of water due to the dry season, presence of water stagnation due to dikes; other factors such as discharges from domestic activities and livestock wastes, and thick vegetation are also present in the river. The relevance of this study is to provide baseline information about the levels of organic matter, NH4-N, and available phosphorus present in the river, provide public knowledge about the negative impacts of excessive levels of those parameters; and locate possible sources of the pollution through the values obtained. For the total phosphorus concentration present in river sediments, the values are ranging from 0.0648 ppm to 0.154 ppm. Therefore, the values of the available phosphorus are harmful and can cause eutrophication to the river. However, for the values of organic matter and nitrogen, it was reported to be not harmful to the river but can still contribute to the excessive nutrient levels and eutrophication of the river.Item Toxicity of the aqueous leaf extract of datilis (Muntingia calabura) on the fry and fingerling of Oreochromis niloticusCagampang, Ma. Hazel C. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1994-08)A 96-hour static bioassay on the effects datilis (Muntingia calabura) leaf extract on the fry and fingerlings of Oreochromis niloticus was conducted to determine the Average Median Lethal Concentration (LC50) of datilis (Muntingia calabura) leaf extract on the fry and fingerlings of Oreochromis niloticus and to describe the behavioral responses of the fish to the extract. The assay consisted of six treatments: 0, 12.5, 25, 50, 100, and 200 ppm concentrations of the extract. Physico-chemical conditions (e.g. temperature, pH, salinity, dissolved oxygen, ammonia, nitrite, and hardness level of water) were monitored. Results showed that the average LC50 at the 12, and 24- hour period of the extract in fingerlings (128.61 and 92.37 ppm) were significantly higher (P<0.05) than in the fry (65.45, and 60,99) respectively. Mortality was higher at higher concentrations than at lower concentrations of the extract. Highest mortality was in 200 ppm followed by 100 ppm, then 50 ppm. No death occurred in 0, 12.5 and 25 ppm concentrations of the extract. Mortality was also significantly higher (P<0.05) in fingerlings than in fry. The fish, exhibited avoidance - response reaction and loss of equilibrium. Possibly, the death and unusual behavior manifested by the fish may be due to saponins present in the extract. Physico—chemical conditions were within the tolerable range for the fish hence, these may not have contributed to the death of fish. This study provides preliminary data on the toxic effects of the aqueous leaf extract of datilis on the fry and fingerlings of ?Oreochromis niloticus.Item Spontaneous formation of silver nanoparticles in humid acid-rich water of Santa Barbara, IloiloCadelina, Mary Dored Ann D. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2018-06)Humic acid (HA) - rich water of Sta. Barbara, Iloilo is successful in acting as a reducing and capping agent in the synthesis of silver nanoparticles (AgNPs). UV-Visible spectroscopy was used to determine the effect of irradiation time, varying HA and AgNO3 concentration, and electrolyte addition. Furthermore, the bactericidal efficacy of AgNPs was evaluated using broth microdilution method. Measurement of AgNPs was done using transmission electron microscopy (TEM). Lower irradiation time (10- 40 min) shows an increasing absorbance trend. However, absorbance decreased and showed bathochromic shifts when irradiated at longer times (50-60 min). AgNP formulations of 40 ppm HA with 4 mM AgNO3 and 50 ppm HA with 4 mM AgNO3 showed the highest peak intensity for varying AgNO3 and HA concentration, respectively. These results were found in both irradiated and un-irradiated samples. Aggregation occurred upon the addition of 50 mM, 100 mM, and 500 mM NaCl but was more prominent at 500 mM NaCl. Dialyzed and un-dialyzed AgNPs have bactericidal activity. However, un-dialyzed AgNP was a more effective treatment because it showed a bactericidal activity up to 1:16 dilution for both Staphylococcus aureus and Escherichia coli as compared to the dialyzed AgNPs which showed a bactericidal activity up to 1:4 for S. aureus and 1:8 for E. coli. The dialyzed AgNPs are polydispersed but were mostly small with sizes less than 10 nm based on the TEM image.Item Heavy metals (Cr, Cu, Pb, and Zn) concentrations of road-deposited sediments within six public plazas in Iloilo CityCaceres, Rizza Daphet E. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2011-04)Contamination from overland transportation is an unavoidable result of urbanization. Cr, Cu, Pb, and Zn arc common heavy metals introduced to the environment by transportation. Road-deposited sediment (RDS) samples were collected from six public plazas (Villa Plaza, Molo Plaza, Mandurriao Plaza, Plaza Libertad, Lapaz Plaza and Jaro Plaza) in Iloilo City from March 2010 to May 2010. 0.5M HC1 was used as extractant and heavy metals (Cr, Cu, Pb, and Zn) concentrations were determined using Flame Atomic Absorption Spectrophotometer (FAAS). The mean concentrations of Cr, Cu, Pb, and Zn in road-deposited sediments from six plazas were 8.79 ± 1.93, 40.90 ± 24.21, 60.74 ± 22.32, and 164.25 ± 25.0 mg/kg, respectively. Metal enrichment of Cr, Cu, Pb and Zn were approximately xl, x8, x7 and x18 more than the background values respectively. There was no significant temporal variation in metals concentrations of RDS between sampling collections. Generally, RDS from Plaza Libertad has the highest metal concentrations. Cu and Pb metals were highly correlated (R2 = 0.891) indicating possible similar sources. A good correlation (R2 = 0.918) was observed between Pb concentration and the number of vehicles that pass along the plaza per hour. Heavy metal concentrations in sediments from plazas have low hazard quotients but bioaccumulation of metals in the body could cause health effects. Efficiency of digestion procedures varied depending on characteristics, texture and composition of road-deposited sediments. 0.5M HC1 digestion was used because it is simple, cost-effective, time-efficient and it leaches out meaningful amounts of bioavailable metals. Using HC1 as extractant simulates human digestion since human stomach contains HC1 that could leach out metals if road-deposited sediments were ingested.Item The adsorption capacity of silica gel and rice hull ash on phenol and anilineBulatao, Ben Fermin P. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2011-04)Chemical waste has been a problem here in the University of the Philippines Visayas, Miagao, Iloilo. Various methods of removal have been utilized. Extraction of silica gel from rice hull and rice hull ash was used to remove organic compounds (phenol and aniline). In this study, silica gel and rice hull ash adsorption on phenol and aniline were investigated with varying contact time and initial concentration. Silica gel reaches its optimum adsorption of both phenol and aniline at 60 minutes contact time. Silica gel was the basis for rice hull ash’s contact time because rice hull ash is 90% by weight silica gel.. Silica gel-phenol system decreases it adsorption capacity as the initial concentration is increased from 25 ppm to 100 ppm. Rice hull ash- phenol system, on the other hand, shows that the adsorption capacity increases as the initial concentration is increased. Both on silica gel-aniline system and rice hull ash- aniline system have increasing adsorption as initial concentration is increased. As the contact time is increased, adsorption increases only until it reaches its optimum adsorption which is 60 minutes contact time where saturation is reached. Increasing initial concentration however has different effect on adsorption on all system explained by the adsorption isotherms. The isotherms show that phenol has the fastest rate to form a monolayer (K and Q°) with the greatest binding strength (b) on silica gel. It is also observed that phenol and aniline formed a monolayer (1/n) on the surface of the silica gel and rice hull ash.Item A quantitative and qualitative analyses of phytoplankton in Lamentao, Barotac Nuevo, IloiloBoglosa, Jescel B. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2000-03)The study was conducted to identify the different genera of phytoplankton in Lamentao, Barotac Nuevo, to determine the distribution and composition of phytoplankton both near shore and offshore and to determine the physico-chemical characteristics in both sampling sites. The samples were obtained near shore (10m) and offshore (15m) for 10 minutes. Towing was done at 12 noon for 200 m. Sampling was done once a month for three consecutive months starting October to December. Each sample was allowed to stand for at least 24 hours. Then these were decanted to have a concentrated sample. Then 1ml sample was introduced in a sedge wick counting chamber for identification and counting under the microscope. The study gave the following findings: There are 32 genera identified in the surface water of Lamentao. Offshore has a higher abundance than the near shore. There are some genera that significantly differ in 2 sampling area shown by the t-test. Density offshore were generally significantly higher than density nearshore. Relative abundance, Leucosolenia sp. and Rhizosolenia sp. have the higher one. There is a higher diversity in off shore than in near shore. Most of the genera is present in both sites and month as shown by the index of similarity.Item Photodegradation of methylene blue in aqueous media using TIO2 -based heterogeneous photocatalysts under natural lightBernido, Julidyn P. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2015-06)This study developed two heterogeneous TiO2-based photocatalysts: pure TiO2 and Fe-doped TiO2 (Fe-TiO2). Heterogeneous catalysts were prepared by coating TiO2 and Fe-TiO2 powder on glass beads. The photocatalytic activity of both heterogeneous photocatalysts were studied by photodegradation of methylene blue in aqueous solution under two pH conditions (6 and 9) and two ionic concentration conditions (0 and 38 ppt). The Fe-TiO2 powder contained minimal amount (2.245%) of Fe as expected. However, surface functionality and ultraviolet-visible (UV-Vis) profile of both TiO2 and Fe-TiO2 powder were very similar indicating that doping did not alter these properties. Between the two heterogeneous catalysts prepared, the amount of Fe-TiO2 catalyst coated on glass beads was lower compared to pure TiO2. The removal of methylene blue was significantly affected by ionic concentration which removal is higher at lower ionic concentration (0 ppt). Although it appeared that the removal of methylene blue was higher at pH 9, statistical analyses revealed that the effect was not significant. In addition, the removal of methylene blue by the two catalysts were significantly different. Heterogeneous photocatalyst based on pure TiO2 showed higher removal of methylene blue in all pH and ionic concentration. Moreover, no interactive effects between variables were observed. Lastly, the blank showed no significant difference on the removal of methylene blue with the heterogeneous photocatalysts which suggest that degradation by direct photolysis from sunlight could be the reason for this result.Item Moss (Brachythecium sp.) and a filamentous green algae (Oedogonium sp.) as bunker oil sorbentsBautista, Norwell Brian C. (Division of Physical Sciences and Mathematics, College of Arts and Sciences, University of the Philippines Visayas, 2007-04)Oil spills are very catastrophic and very destructive events. One way of controlling the dispersion of oil from these spills is by the use of sorbents. The procurement of commercial sorbents can be very costly. Thus, this study analyzed and evaluated the efficiency and effectivity of moss (Brachythecium sp.) and a green filamentous algae Oedogonium sp. as substitutes for commercial sorbents. Brachythecium sp. can grow in any moisture—rich environment and Oedogonium sp. algae grow freely in fish ponds and in any body of stagnant, oxygen-poor water. Thus, both samples are very abundant in the environment. Sorption capacity results showed that the moss Brachythecium sp. and the algae Oedogonium sp. can sorb five times and seven times its weight, respectively. In comparison, Peat Sorb, a commercial sorbent, was recorded to sorb 15 times its weight (Emedco, 2007). The minimum sorption capacity of the moss and algae samples was recorded to be approximately equal to their weight. The adsorption isotherms of both samples follow the Langmuir plot for monolayer adsorption. In the hexane capillary rise experiment, hexane rose significantly in ground moss (72.25 mm in 7 min.) and unground moss (64.80 mm in 7 min.) compared with unground algae (23.52 mm in 7 min.) and (20.70 mm in 7 min.), indicating that moss is more hydrophobic. In water, capillary rise, on the other hand, unground algae is a better medium (5.76 mm in 4 min) compared to the rest (ground algae - 4 mm, unground moss - 5.29 mm, and ground moss — 4.11 mm, all in 4 min.). Results also revealed that the moss Brachythecium sp. and the algae Oedogonium sp. expressed hydrophobic characters in the hexane-water system by remaining in the hexane layer after agitation. The moisture content of the algae (14.85%) is twice that of moss (7.94%). This gives the moss an advantage in oil sorption. The lipid contents of algae (15.58%) and moss (11.47%) do not comprise the majority of their biomass, but the lipids aid in increasing the samples’ affinity for non-polar substances. The samples may not sorb as effectively as the commercial sorbents, but they are abundant in the environment, thus, a cheaper alternative. Like Peat Sorb, which was processed from the biomass of Sphagnum sp. moss, the samples may undergo the same process that increases the hydrophobicity several-fold and gives oil-biodegradation capabilities.
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