Adsorption of Nickel on Vertisol: Effect of pH of soil Organic Matter and Co-contaminants

Sathya V. and Mahimairaja S.

Nickel (Ni), one of the toxic heavy metals is widely distributed in soil and water ecosystem. Its impact on environment mainly depends on the chemistry of soil. To predict the problems associated with the toxicity of Ni, a better understanding of adsorption and desorption of Ni is required. Adsorption is the foremost process which occurs when metals come in contact with the soil. In this study a series of laboratory batch experiments were conducted to study the adsorption and desorption behavior of Ni in soil. For adsorption of Ni, the equilibrium period was found that 12 hours and the maximum adsorption (90.45 mg kg-1) was obtained with the highest concentration of Ni added (100 mg kg-1). To describe adsorption kinetics, zero-, first-, second-, third order reaction, parabolic diffusion and Elovich equations were tested for goodness of fit by least square regression analysis. Among the different kinetic models, third-order reaction (R2=0.998), parabolic diffusion (R2=0.829) and Elovich (R2=0.922) reaction were described by the adsorption of Ni adequately with high coefficient of determination. Langmuir isotherm (R2=0.72) was best fit for adsorption of Ni when compared with Freundlich isotherm (R2=0.39). Further the effect of pH of soil, organic matter content and presence of co-contaminants on the adsorption of Ni was studied. The Ni adsorption was increased with increasing pH levels. The maximum adsorption of Ni (94.84 mg kg-1) was found in the pH of 9. The organic amendments were decreased by the adsorption of Ni in soil. The adsorption was higher in control (93.18 mg kg-1) than the organic amendments added soil. The presence of co-contaminants significantly affected the adsorption of Ni. The Ni adsorption decreased due to the presence of Cd but increased in the presence of Cr. Desorption behavior of Ni in soil was also observed in this study by using different extractants such as DTPA and Ca(NO3)2. DTPA has desorbed more amount of Ni (82.9 %) from soil than Ca(NO3)2 (33.8 %). From the results it is inferred that the adsorption and desorption behavior of Ni is the basis for prediction of toxicity effects of Ni in soil.

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Investigation of Pb Ions interaction in Troponin C of the skeletal muscle

Mahdavian Leila

In recent years many of human diseases are caused by the arrivalof heavy metal ions such as lead ions to human bodyin differentways. One of the diseases of lead ions ismuscle painand muscle relaxation. Muscle contraction is a result of actin and myosin sliding on each other. Rate and mechanism of Ca2+ exchange in troponin C in the skeletal muscle is the key point for understanding this interaction. In this study, we have investigated Pb2+ interaction with NH2 and COOH terminals of troponin C (sTnC) on actin filaments in skeletal muscle. Initially, the effect of replacing lead ions with calcium in the positionofamine andcarboxylis examinedto usethemolecularmechanics (MM) force field of MM+, Amber and BIO+ (Charmm).

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Production of Green Fuel Briquette from Glycerol Waste mixed with Coal Powder and Cow Dung

Boonyawanich Siriorn, Pisutpaisal Nipon and Haosagul Saowaluck

This research aims to produce green fuel briquettes from glycerol waste mixed with an agricultural waste (cow dung) or an industrial waste (sub-bituminous coal powder). The briquettes were synthesized by varying the ratios of glycerol waste to coal powder/cow dung at 30:60, 45:60, 50:60, 60:60, 60:45 and 60:30 (w/w) respectively. The heating value and the strength of all briquettes were measured. The briquettes with the heating value above 3,000 calg-1 were further developed by the addition of binders, gum arabic or cassava starch. Without the addition of the binders, the glycerol-coal powder and glycerol-cow dung with the mixture ratios of 45:60 and 60:30 yielded the best coal properties. The glycerol waste-coal powder mixture of 45:60 showed the heating value, strength, moisture content, volatile matter, fixed carbon and ash content of 5,469 calg-1, 1.76 MPa, 2.4%, 63.9%, 21.3% and 12.3% respectively while the glycerol waste-cow dung mixture of 60:30 showed the heating value and strength of 4,269 calg-1 and 0.21 MPa respectively. The addition of the binders did not improve the heating value and strength.

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Biogenic synthesis of silver nanoparticles using aqueous floral extract of Azadirachta indica and its Anti-Candida and larvicidal activities

Busi Siddhardha, Hnamte Sairengpuii and Rajkumari Jobina

The aim of this study was to develop a rapid biological method for the synthesis of silver nanopar-ticles using aqueous floral extract of Azadirachta indica. The phytochemicals present in the aqueous floral extract were responsible for reducing silver ions to silver nanoparticles. The synthesized AgNPs were characterized by using UV-Visible spectroscopy where the surface Plasmon resonance was obtained at 420nm. Further the AgNPs were characterized by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) analysis and dynamic light scattering (DLS) measurement. TEM micrographs showed the formation of smooth surfaced, polydispersed and spherical shaped silver nanoparticles in the size range 35-60 nm. FTIR analysis revealed the presence of functional groups in the synthesized silver nanoparticles. Minimum inhibitory concentration (5µg/ml) and minimum fungicidal concentration (7.5µg/ml) of AgNPs was established against Candida albicans. The synthesized AgNPs showed significant larvicidal effects on third and forth instar larvae of Aedes aegypti after 24 h of exposure. The LC50 and LC90 values against third instar larvae are 3.99 and 10.92 mg/L respectively. The lethal concentrations observed against forth instar larvae are LC50=4.35 and LC90=11.88 mg/L.

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Synthesis and charcterization of the complexes of humaic acid (extracted from Azraq soil Jordanian ) with some divalent cations

Abualreish M. J. A., Al msiedeen A.M. and El-eswed Bassam

Humic acid (HA) was extracted from the soil of Azraq oasis lying in the Jordanian desert 100 km east of the capital Amman. The complexes of the humic acid with the divalent cations Cu2+, Ni2+, Zn2+ and Co2+ were prepared. The prepared metal–humic acid complexes were characterized by elemental analysis, FT-IR, thermo gravimetric analysis (TGA), X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). Fourier transform infrared (FT-IR) analysis indicates that cations Cu2+, Ni2+, Zn2+, and Co2+ are bound to HA primarily through bidentate carboxyl functional groups. Elemental analysis of the HA indicated that the carbon, hydrogen and nitrogen percents are close to that of the Temple Northeastern Birmingham (TNB) model of HA. The % metal ions in HAs complexes ranged from 4 to 10 %. The thermo gravimetric analysis (TGA) of HAs complexes indicated the order of thermal stability as: Zn-HA > Cu-HA > Ni-HA > Co-HA. The SEM study of HAs complexes does not reveal clear changes of HAs surface upon complexation. The X-ray diffraction pattern of HA in the 2θ range from 0 to 60° exhibited very small diffuse peaks with a few intense peaks, implying their non-crystalline nature. The HA was dominated by the graphite mineral matrix which is disturbed by complexation with metal ions.

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Removal of colour and COD of Distillery Effluent by Electrochemical- Oxidation Method

Arulmathi P., Elangovan G. and Sivakumar K. K.

Distillery industry is recognized as one of the most polluting industries in India with a large amount of annual effluent production contributing highly to water pollution. Colour, COD, and suspended solids are the crucial pollution problems of the Distillery industry. In this present study, the viability of electrochemical treatment process was reported to treat the colour and COD of distillery effluent using with Ti/Pt as an anode in batch mode. The effects of the operating factors such as electrolyte concentration, pH, current density, reaction time, agitation speed and distance between electrode were studied. During this process the best removal efficiency obtained were around 95% of colour and 79% COD. The concentration of electrolytes plays vital role in this present study.

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Decrease in Unlikely Components by Non-Hydrodesulphurization Process using Fenton’s Reagent as Oxidizing Agent to meet Environmental Standards

Mohammed Aslam Abdullah and Thirunavukkarasu Sekar

Sulphur compounds are one of the most important impurities in various petroleum fractions that cause serious devastating to earth’s environment. Integration of Non-Hydrodesulphurization Process with Hydrodesulphurization process can bring benefits to produce ultra-low sulphur diesel fuels. Using the hydrotreated Kakinada diesel fuel as a feedstock, oxidation process during Non-Hydrodesulphurization process has been studied using Fenton’s reagent without ultrasound for effective removal of sulphur. This technique without extraction and adsorption has resulted in 69% removal of sulphur. It shows a good synergic effect when extraction and adsorption are integrated with Oxidative desulphurization using Fenton’s reagent. Under the best operating conditions of 65oC and atmospheric pressure the sulphur content present in the diesel fuel has decreased from 766 µg/g to 6.04 µg/g. This is equivalent to 99.82% of sulphur removal and is 1.09 times better than Bharat IV norms.

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Adsorption of Organic Dye on to Novel Magnetic Biocomposite: Kinetics and Equilibrium Studies

Sivashankar R., Susheeba O.K. and Sivasubramanian V.

The magnetic biocomposite (MBCs) was synthesized using co-precipitation method and applied as a highly efficient adsorbent for the sequestration of organic dye from aqueous solution. Methylene blue (MB) was selected as a model cationic dye to examine the adsorption behavior of magnetic composite. A very fast adsorption rate was observed by the non-immobilized adsorbent compared to immobilized adsorbents and could be well described by the pseudo second order kinetic model. The effect of initial solution pH, initial concentration, agitation speed and contact time was systematically investigated. Langmuir monolayer capacity had a mean value of 232.66 mg/g. The adsorption performance of methylene blue on to MBCs was strongly dependent on initial solution pH. Further, the recycling experiments showed good reusability of MBCs.

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Purification and flux decline of protein solution using series model through modified cellulose acetate ultra-filtration membrane

Gajendran T. and Stalin N.

Flux decline of BSA protein solution during ultra-filtration (UF) was quantified by resistance in series model. Resistance against the solvent flux was assumed to be comprised of four components which are membrane hydraulic, adsorption, pore plugging and fouling resistance independently. Flat sheet ultra-filtration membrane was prepared by cellulose acetate (CA)/Low cyclic dimer poly sulfone (LCD PSf) and N-N-Dimethyl formamide (DMF) as solvent by phase inversion method. The hydrophobic nature of polysulfone is reduced by blending the polymer solution with additive polyethylene glycol of different molecular weights (PEG 000, PEG 200, PEG 400, PEG 600). The experiments were conducted in a stirred continuous mode with protein solution, the range of transmembrane pressure drops from 344.7 to 68.9 at a constant stirring speed. The effect of pore plugging resistance and fouling layer resistance with increase of time and pressure was examined by using protein solution.

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Chemical Speciation of Zinc and their Availability to Wheat in Typic Haplusterts as influenced by Zinc Fertilization

Keram K. S., Sharma B. L. and Sharma G. D.

The results of comprehensive field experiment revealed that the application of Zn @ 2.5, 5, 10 and 20 kg ha-1 significantly increased DTPA-extractable Zn, WS-Zn, EX-Zn, CMPLX-Zn, ORG bound-Zn, CRAMOX bound-Zn, CRYOX bound-Zn and total-Zn at 0, 15, 30, 60, 90 and 120 DAS as compared to control. However, the DTPA-extractable Zn, WS-Zn, EX-Zn, CMPLX-Zn, ORG bound-Zn, CRAMOX bound-Zn, CRYOX bound-Zn and total-Zn reduced with ascending days after sowing (0 to 120 DAS). The maximum residual-Zn was observed with the application of 1.25 kg Zn ha-1 at 15, 30, 60, 90 and 120 DAS. Further, it was revealed that the fractions contributing directly and positively to total-Zn are WS-Zn, EX-Zn, CMPLX-Zn, ORG bound-Zn, CRAMOX bound-Zn, CRYOX bound-Zn and residual-Zn and indicate the influence of these fractions on availability of Zn in soil under field condition. The per cent contribution of all the fractions to total-Zn decreased with the increasing days after sowing (0 to 120 days) while the contribution of residual-Zn was maximum and increased with ascending days after sowing.

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Polycyclic aromatic hydrocarbons in processed meats: A toxicological perspective

Nisha A.R., Dinesh Kumar V., Arivudainambi S., Umer M. and Khan M.S.

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants caused by incomplete combustion of organic materials. These compounds are also found in food as a result of food processing like curing, drying, smoking, roasting, refining and fermentation. The acute exposure of these compounds is not common whereas chronic exposure causes hazardous heath effects including carcino-genicity and mutagenicity. This article reviews the health effects of Polycyclic aromatic hydrocarbons, formation of PAHs by different meat processing procedures like smoking, grilling, cooking and procedures for the reduction of PAHs in the processed meat. Smoking and grilling are the major processing procedure leading to high concentration of PAHs in meat when compared to other cooking procedures. There are relatively rare experiments to alleviate PAH content in processed meat. Sugar smoking, low density polyethylene and ultraviolet irradiation are some suggested methods.

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Nanoscale Zero Valent Iron supported on solid support as an advanced material for the environmental purification: A Review

Thakare Sanjay R., Thakare Jyoti and Kosankar P.T.

Nanoscale zero-valent iron (nZVI) particles are typically 5–40 nm sized particles that rapidly transform many environmental contaminants to benign products and are promising in situ remediation agent. Due to their small size and increased reactivity, these manufactured nanoparticles have the potential to be more effective than the microscale ZVI that is already in use for contaminant remediation in soil and groundwater aquifers. In recent years, the use of nanoscale zero-valent iron (nZVI) for the treatment of toxic contaminants in groundwater and wastewater has received wide attention and encouraging treatment efficiencies have been documented. This report examines the literature on nanoscale ZVIs, their potential use as decontaminants of various organic as well inorganic pollutants and ways to enhance their activity. Most of the research to date has looked at the reductive potential of ZVIs but it has been reported that zero-valent iron (ZVI) can actually catalyse oxidative degradation in a Fenton-type reaction. Thus this report also explores Fenton-type degradation. The report also examines methods of incorporating nanoscale ZVI particles onto solid supports which may be useful for increasing the lifetime, activity and usability of the particles. Finally, possible challenges to developing ZVIs as a decontaminant are discussed.

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