Research Journal of Chemistry and Environment

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Research Journal of Chemistry and Environment

Antibacterial, antioxidant and cytotoxicity activities of extracts from Hericium erinaceus

Lin Yin, Wei Han and Ke Yuan

Using Hericium erinaceus as research objects, we concentrate extract of Hericium erinaceus which is extracted by methanol as solvent. The concentrated liquid is dispersed in water, extracted with petroleum ether, ethyl acetate, n-butanol extraction respectivly. The ethyl acetate extract was purified by silica gel column chromatography, eluted gradient with solvent of different polarities to get the different fraction. The slope tube method was established to determine the antibacterial activity of plant pathogens in vitro by MIC value while the antioxidant activity in vitro was determined by three methods. The shrimp larvae is used as the research object and the experiment of the shrimp lethal biological activity is targeted to preliminarily screen the cytotoxic activity in different parts of Hericiumm erinaceus methanol extract. The experiment results show that different methanol extract fractions of Hericiumm erinaceus had certain antibacterial activity and antioxidant activity. There is a clear does-effect relationship in which the ethyl acetate extract has the strongest antibacterial activity while the antioxidant capacity of the n- butanol fraction is the strongest. The various extracts of Hericium erinaceus by methanol also have some cytotoxic activity where as in the ethyl acetate fraction, the fraction (CH2Cl2:CH3OH=1:1) is the strongest.

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Numerical Simulation Study on Non-Darcy Seepage Mechanism in micro-pore based on the Micro-fluidic Boundary Layer Theory

Liu Jianjun and Song Rui

Accurate prediction and understanding of the non-Darcy seepage mechanism contribute to the macroscopic physical properties of the porous media such as conductivity, permeability, formation factor, elastic moduli etc. Multiscale simulation of transport in porous media requires microstructure models. Different types of porous media models have been established based on the capillary tubes of different diameters. Boundary layer reflects the resultant effects of the physical conditions of the reservoir and fluid (reservoir porosity, permeability, fluid viscosity) and the conditions of development (pressure gradient, etc.).Based on the micro-fluidic boundary layer theory and the Navier-Stokes equation, the models are simulated in microscopic scale in Fluent software in case to acquire seepage velocity field graph and study on how the interaction force between fluid and solid, the fluid viscosity, the pore diameter and the pressure gradient affects the effective circulation aperture of the pore and the seepage flow rate.

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Environmental Effects of Nano Additive Co3O4 in Grape Seed Oil biofuel fuelled in CI Engine

Karthikeyan S., Elango A., Prathima A. and Raja K.

The present analysis is to study the effect of nano additives of Cobalt Oxide (Co3O4) on the performance and emission characteristics of GSOME (Grape Seed Oil Methyl Ester) biodiesel (B20) in a four stroke, single cylinder, air cooled and direct injection diesel engine. The Co3O4 nano particle size range is less than 100 nm. The additive (Co3O4) was added to B20 at a dosage of 50ppm and 100ppm. The GSO(Grape Seed Oil) was mixed with Co3O4 nanoparticles with the aid of an ultrasonicator. The fuel properties of D80B20, (80% Diesel + 20% GSOME), D80B20 Co3O450 (80% Diesel + 20% GSOME +50ppm Co3O4 nano particles), D80B20 Co3O4100 (80% Diesel + 20% GSOME+100ppm Co3O4 nano particles) were studied and compared according to ASTM standard test methods for biodiesel. It was noticed that the addition of nano cobalt oxide additive acts as an oxygen buffer which improves the combustion, brake thermal efficiency and reduces specific fuel consumption at full load conditions. The Co3O4 nano additive resulted in maximum reduction in hydrocarbon (HC), carbon monoxide (CO), smoke opacity and oxides of Nitrogen (NOx) at full load operation.

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Removal of Humic Acid from Synthetic Water using Chitosan as Coagulant Aid in Electrocoagulation Process for Al and Fe Electrodes

Seid-Mohammadi A., Asgari G., Samadi M. T., Ahmadian M. and Poormohammadi A.

Humic Acid (HA) is one of the polyelectrolyte compounds which cause many problems in water treatment process. The removal of this organic compound from drinking water is recommended due to its toxicity and health risks. In present study, comparative experiments were carried out using aluminium (Al) and iron (Fe) as the electrode material in Electrocoagulation Process (ECP) using chitosan as a natural coagulant aid for removing HA in synthetic water. Also, the effects of main operational parameters including pH, current density, HA initial concentration and different chitosan concentrations were investigated separately. Results indicated that the optimum conditions were obtained at pH=6, current density= 20 mA/cm2, HA initial concentration=5 mg/L and chitosan concentration=2 mg/L. Experimental results expressed that in chitosan concentration of 2.5 mg/L, the process efficiency with Al electrode was 90%. Also, in the optimum condition, removal efficiency of HA were 83% and 63%, for Al and Fe electrodes in ECP without chitosan respectively. Al electrode will be a better choice as compared with Fe electrode in ECP for removing HA. On the other hand, using chitosan as a coagulant aid could improve the efficiency and can be used as a convenient and cost-effective coagulant aid.

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Utilization of Base Modified Oil Palm Fiber for Removal of Cd(II) from Aqueous Solution

Nor Aimi A. W., Norain I.,, Nor Aziyah B., Nurul Izza H., Vicinisvarri I. and Mas Rosemal Hakim M. H.

The potentiality of base modified oil palm fiber (OPF) in the removal of Cd(II) in aqueous solution was investigated as compared to commercial activated carbon (AC). Base modification of OPF were carried out by using dilute solutions (0.013 M) of NaOH, KOH and Ca(OH)2. A series of experiment were conducted in a batch system to assess the effect of the system variables i.e. initial pH (3-9), contact time (10-120 min) and initial metal ion concentration (5-15 mg L-1). The results indicated that at 5 mg L-1, the adsorption percentage increases in the order of Ca(OH)2-modified OPF (92.75 %) < NaOH-modified OPF (97.51 %) < KOH-modified OPF (99.28 %) < AC (99.96 %) at an initial pH value of 7. Equilibrium data were fitted to the Freundlich and Langmuir isotherm equations and the equilibrium data were found to be well presented by the Langmuir isotherm equation. Pseudo-first order and pseudo-second order kinetic model were employed to describe the adsorption mechanism. The kinetic data were found to fit pseudo-second order kinetic model with good correlation coefficient. The experimental data obtained in this study indicate that base modified OPF could be employed as a low cost adsorbent for the removal of Cd(II).

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Heterogeneous Photocatalysis of Methomyl and Metalaxyl using TiO2 supported over Activated Carbon

Ibrahim Khalil M., Musleh Salem M., Nabeh Inas and Al-Akasheh Talal

Heterogeneous photo catalysis degradation of agrochemicals under UV-irradiation and sunlight was investigated. A laboratory set up was designed to evaluate the optimal oxidation process for the stable, hazardous water-soluble methomyl and metalxyl. The degradation depends on the concentration of the pesticides, H2O2, H2O2/TiO2 ratio and the percentage of the activated carbon. The photolysis of both pesticides under light (UV or sunlight) was confirmed and the solar photolysis results were not more 5% for both pesticides after a sufficient time. The reaction parameters were changed and studied under UV-irradiation, both substances undergo pseudo first–order reaction but a red deviation was observed with high initial metalaxyl concentration. On the other hand, the increase in catalyst concentration causes an increase of the screening effect. An electron acceptor H2O2 was added in the presence of O2, the reaction initial rate was unaffected at low H2O2 initial concentration (<0.0092% (v/v)). Results did not differ when using the same parameters under sunlight instead of UV-irradiation. Finally pretreated wastewater samples containing methomyl/metalaxyl under these conditions produce higher mineralization efficiency in relatively short radiation time under these optimum conditions.

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Enhancement of Esterification of Propionic Acid with Ethanol by Pervaporation Reactor

Rathod Ajit P., Wasewar Kailas L. and Sonawane Shriram S.

Pervaporation reactor is a combined process of chemical reaction and separation in ex-situ type has fascinated much concentration for its overcoming capacity of the equilibrium conversion. Pervaporation reactor shows potential preference to increase conversion in reversible esterification reactions, generating water as a byproduct. In present work, polyvinyl alcohol-polyether sulfone (PVA-PES) composite hydrophilic membrane was used for pervaporation-assisted esterification of propionic acid with ethanol. Pervaporation reactor is a water selective pervaporation membrane module combined with esterification reactor. Effects of various parameters such as process temperature, initial mole ratio of ethanol over propionic acid, the ratio of the effective membrane area over the volume of reacting mixture and catalyst concentration on the performance of pervaporation reactor were discussed. The following optimum conditions were obtained: temperature = 80°C, catalyst concentration = 0.416 kmol/m3, initial molar reactant ratio (ethanol / propionic acid) = 2, ratio of effective membrane area to the reaction volume = 16.84 m2/m3. The presented data can be extended for study and design of pervaporation reactor for comparable type of reactions.

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Investigation of color removal from real textile wastewaters in ABR followed by ozonation as post treatment

Hatice Ozbebek, Sebnem Ozdemir, Dilek Akman, Kevser Cirik and Ozer Cinar

The textile industry wastewaters are known as one of the main sources of severe pollution problems worldwide. In particular, the release of highly colored effluents is undesirable, due to toxic and resistant effects to the environment. In this study, four stage anaerobic baffled reactor (ABR) with a working volume of 19 L was fed with real textile effluent containing about chemical oxygen demand (COD) of 1000mg/L, color of 80.2 m-1(λ436), 89.9 m-1(λ525), 95.7 m-1(λ620), 3335 Pt-Co and assessed under varying operational conditions. Initially effect of glucose as external substrate on ABR performance was assessed. COD and color removal efficiencies of the ABR reached to 66.9% and 88% when influent COD was increased to 2000 mg/L by external substrate addition. Additionally, ozonation was applied followed by anaerobic treatment to investigate the removal of the residual color and COD. The overall COD and color (Pt-Co unit) removal efficiencies via post-ozonation were 41.7% and 68.5% respectively for ozonation time of 75min.

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Performance of a full scale upflow anaerobic sludge blanket reactor for the treating distillery wastewater

Saner A. B., Mungray A. K. and Mistry N. J.

Performance of a full-scale upflow anaerobic sludge blanket (UASB) reactor having capacity 450 m3 day-1 for the treatment of distillery spent wash is evaluated in this paper. The designed hydraulic retention time (HRT) of the plant was 18.67 days having average inlet COD of 83340.00 mg l-1. The pH of the raw spent wash was in between 3.42 to 5.84 and the pH of the effluent coming out of the UASBR was varying in between 6.54 to 8.75 during the study period. The ratio of VFA/Alkalinity was in between 0.25 - 0.48 which shows stable conditions of the reactors during the study period. In the plant, the overall average percentage removals of COD, BOD3 and TS were 71.56, 38.15 and 26.82 respectively at an OLR of 0.92 - 5.03 kg COD m-3 day-1. Biogas produced was stable in the range of 1300.00 – 18870.00 m3 day-1. Sludge profile in UASB reactor and its characteristics such as COD, TS including COD mass balance was also done for the insite performance of the reactor. Sludge profile indicates decreasing trend of solids up to 6th port from bottom and found increased at the7th port. COD profile also shows decreasing trend with increase in the height of the reactor. Study summarizes that the treatment of the distillery wastewater by biological treatment using UASB reactors has a major role in the reduction of polluting parameters as well as producing biogas as renewable energy source.

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Treatment of biodigester effluent of a maize based starch industry by coagulation

Mazumdar Bidyut and Chaudhari Parmesh Kumar

Biodigester effluent (BDE) from maize based starch industry wastewater (MSIWW) was treated with inorganic coagulants, FeCl3, Alum and Polyaluminum Chloride (PAC) and Moringa oleifera seeds, a natural coagulant, for the removal of the color and for the reduction in the chemical oxygen demand (COD). The coagulation yielded about 64%, 63% and 50% COD reduction when treated with FeCl3, Alum and PAC respectively. When the Moringa oleifera seed extract was used as coagulant, the reduction in COD was 53%. Color reduction was 64%, 69% and 75%, when biodigester effluent (BDE) was treated with FeCl3, alum and PAC. No appreciable color change was observed with Moringa oleifera. The coagulation/flocculation is affected by pH and optimum pH was found to be pH 9 for Moringa oleifera and pH 6 for FeCl3, alum and PAC. Settling and filtration studies were also done on coagulated/flocculated effluent. The process can be applied to treat the effluent which will be suitable influent to membrane separation unit to make the effluent recyclable.

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Optimization of Polycyclic Aromatic Hydrocarbons extraction efficiency from selected processed meat using different methods

Olatunji O. S., Opeolu B. O., Fatoki O. S. and Ximba B. J.

The efficiency of recovery of five polycyclic aromatic hydrocarbons (PAHs), namely phenanthrene, benzo[k]flouranthene, benzo[a]pyrene, indeno[123-cd]pyrene and benzo[ghi]perylene from processed meat was evaluated using hydrolysis/ liquid-liquid extraction and microwave assisted extraction procedures. Beef stripes and chicken fillets were bought at the butchery and processed to edibility by smoking and grilling. The meat samples were hydrolysed and the PAHs extracted in n-hexane using liquid-liquid extraction and microwave assisted extraction procedures. The extracts were subjected to column cleaned-up and quantified for the PAHs fractions using Gas Chromatography-Flame Ionisation Detector (GC-FID). The recovery of the 5-PAHs using hydrolysis/liquid-liquid extraction procedure was significantly (p<0.05) high for all meat samples than hydrolysis/microwave assisted extraction technique. The mean concentrations (µg/kg) of phenanthrene, benzo[k]flouranthene, benzo[a]pyrene, indeno[123-c,d]pyrene and benzo[ghi]perylene extracted by MAE from the grilled and smoked-processed beef were <0.001, 3.197±1.118, <0.001, 4.359±0.526 <0.001 respectively and 10.446±0.675, 4.550±1.360, <0.001, 20.987±7.222, <0.001 respectively, while their mean concentrations (µg/kg) of in extracts recovered by liquid-liquid extraction from grilled and smoked-processed beef were <0.001, 1.068±0.001, 0.794±0.042, <0.001 0.755±1.070 respectively and <0.001, 2.241±1.191, <0.001, 1.499±0.042, 1.703±0.451 respectively. Also, the levels of PAHs detected in the different processed meat samples were dependent on the processing method; with those smoked- showing higher PAHs concentrations than in grilled-processed beefs. The concentration of indeno[123-cd]pyrene in smoked processed beef samples was relatively higher than the other PAH fraction determined. Results also showed that recoverable PAHs concentrations in the different meat samples are a function of the meat type and processing methods.

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Spectrophotometric Study of the Ligand Exchange Reaction between Potassium Hexacyanoferrate(II) and Schiff’s Base derived from Salicylaldehyde and Sulphanilamide (SASN) Catalyzed by Mercury(II) Ions

Ramachar T., Rafi K. M., Umamahesh M. and Fathima Nuzhath

Potassium hexacyanoferrate when mixed with the Schiff’s base derived from Salicylaldehyde and Sulphanilamide(SASN) at pH 3 in 20% v/v dimethyl formamide (DMF) in the presence of mercury(II) ions forms an intense reddish brown colored species. The maximum color development occurs in 30 minutes after mixing. The color formation is spectrophotometrically monitored under the established optimum experimental conditions. The optimum experimental conditions established are: pH 3, 20% v/v DMF solvent, 520 nm as wavelength of maximum absorbance, 2 fold excess of hexacyanoferrate(II) to Schiff’s base SASN, 1 x 10-5M concentration of Mercury(II). The color reaction is successfully investigated for the spectrophotometric determination of Schiff’s base SASN in the range 0.20mg/ml to 2.0 mg/ml when Hg(II) concentration is kept fixed. In the same way, when the concentration of SASN is fixed, the method is successfully explored for the spectrophotometric determination of Hg(II) in the range 0.2 µg/ml to 1.4 µg/ml. The proposed method can be suitably applied for the spectrophotometric estimation of SASN and also Hg(II).

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Biogas Generation through Anaerobic Digestion Process-An Overview

Deepanraj B., Sivasubramanian V. and Jayaraj S.

Depleting petroleum resources, ever increasing petroleum price and the rapid addition of greenhouse gases into the atmosphere rekindle the researchers to develop new techniques to obtain clean and sustainable energy from the renewable sources. There are many such resources existing in reality and ready to serve the mankind on demand. Out of the many renewable options, wind, solar and biomass energies are considered as the major sources. This paper focuses on biogas technology which is a very attractive way to utilize biomass sources for fulfilling partial energy requirements. Biogas system can provide multiple benefits to the users and aid to protect the environment. Biogas systems produce biogas through digestion of organic materials. All biodegradable biomass materials are suitable for feeding into biomass digesters. Common feedstock includes agricultural wastes, crop residues, animal wastes, forest residues etc. This paper presented an overview of anaerobic digestion process including various stages and microorganisms involved in the biogas production, the parameters that affect biogas production, types of digesters and the byproducts. It also discusses the results of the experiments conducted using various feedstock.

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