Efficiency of reverse osmosis in removal of total organic carbon and trihalomethane from drinking water

Rajamohan R., Venugopalan V. P., Mal Debasis and Natesan Usha

During chlorination, the natural organic matter present in water reacts with chlorine and leads to the formation of trihalomethanes. Trihalomethanes are known for their carcinogenic characteristics. Removal of THM and DOC from the source water, therefore, is an important task in the water purification process. With the aim of removal of THM and its precursor natural organic matter from the water, a laboratory scale study was carried out using reverse osmosis process. In this study, drinking water dosed with chlorine or an alternative disinfectant, chlorine dioxide, was passed through a micro filter, an activated carbon filter and a reverse osmosis membrane. The RO membrane removed 83.8% of THM from the drinking water source.

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Salinization of groundwater in semi-arid zone: an example from Fetzara Lake, North-East Algeria

Fekrache Fadila and Djamai Rachid

Groundwater salinization has become a crucial environmental problem worldwide and is considered the most wide spread form of groundwater contamination. The origin of salinity in the coastal aquifer of the Fetzara Basin, Algeria was investigated by means of chemical analyses of groundwater samples from 25 wells. The groundwater samples present a clear gradation from bicarbonate sodium salinization to that of sodium chloride. The saturation indices for calcite, gypsum, halite, dolomite and anhydrite and binary diagrams of different ions indicate the existence of various salinization processes such as the dissolution/precipitation of minerals. Statistical analysis can be an important tool to identify and classify different sources of groundwater salinization. This paper refers to the application of Principal Components Analysis (PCA) as an effective technique for the identification of major constituent ratios which can be used for efficiently identifying various salinity sources.

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Investigation of Greenhouse Gas Emissions from Alternative Waste Management Strategies in Tehran by Waste Reduction Model (WARM)

Fahimeh Rahimi, Farideh Atabi, Jafar Nouri and Ali Omrani Ghasem

The goal of this study is the calculation and verification of greenhouse gas (GHG) emissions along the waste management system by means of waste reduction model (WARM). Climate change and greenhouse gas emissions have become a focal environmental issue around the globe. In this context, the present work describes an environmental life cycle analysis of waste management system, comparing two possible strategies in Tehran. The purpose of this study was to identify and assess the trends in greenhouse gas emissions associated with waste management system in Tehran. The waste reduction model was used to determine greenhouse gas emissions from baseline and alternative waste management including source reduction, recycling, combustion, composting and land filling. The results illustrate source reduction; reuse and recycling of materials which can reduce greenhouse gas emission and manage materials more sustainable. It can help waste managers and policy-makers to recognize the best options for greenhouse gas reductions during the materials management.

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Efficacy of biosynthesized silver nanoparticles as antimicrobial agent against Staphylococcus aureus and Escherichia coli by using Plectranthus barbatus (coleus forskohlii) aqueous root extract

Manikandan D., Thenesh Kumar S. and Nagendra Gandhi N.

Bio-reduction of silver nitrate (AgNO3) was used for the synthesis of silver nanoparticles respectively with the Plectranthus barbatus (Coleus forskohlii) root extract. These biosynthesized silver nanoparticles were characterized using UV–VIS spectroscopy followed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The results showed that the roots extract of Plectranthus barbatus is an excellent bioreductant for the synthesis of silver nanoparticles. Therefore, obtained silver nanoparticles exhibited good antibacterial activity two human bacterial pathogens such as gram positive (Staphylococcus aureus) and gram negative bacteria (Escherichia coli).

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Regeneration of Iodate loaded resin using multi atomic anions

Ratnesh Kumar, Mishra Ajay Kumar and Seshadri K. S.

The basic philosophies of waste management are delay and decay, dilute and dispersal and concentrate and containment. In addition to these, the recent option for waste management is recycle and reuse which arose due to the existence of precious elements available in the waste stream which when picked up judiciously can be put to use for their applications. The spent resins generated in the nuclear reactor was considered as waste and was subjected to disposal before thought about the pickup of precious elements it contains. It contains essentially cesium, strontium, cobalt iodide, iodate etc. with active loading to the extent of 0.1Ci./m3 and surface dose of the order 5 R. It is necessary to convert the spent reins into innocuous, non-leachable form. An attempt has been made to convert the simulated spent resin into multivalent ionic form in batch as well as in column studies to use the regenerated resin for uptake of radioactivity and minerals. Conditions favoring highest percentage exchange were attempted by using regenerant of higher concentration and smaller solid to solution ratio in the batch studies and optimized flow rate in the column studies to regenerate completely the active resin into inactive form.

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Utility of Ceric Ammonium Nitrate (CAN) in Organic Synthesis: An Efficient One-pot Synthesis of Spiro [indoline-3, 4-quinazoline/pyrimidine]ones

Lahsasni S., Mohamed M. A. A. and El-Saghier A. M. M.

Some new spiro[indoline-quinazoline/pyrimidine]ones were synthesized via a novel three-component Biginelli-like reaction between isatin, cyclic or acyclic 1,3-dicarbonyl compounds and urea, or thiourea in one pot reaction.

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Ameliorating effect of Trigonella foenum-graecum L. (Fenugreek) against diesel and petrol exhaust nanoparticle induced toxicity in H9C2 cells

Mohan Durga, Soundararajan Nathiya and Thiyagarajan Devasena

Trigonella foenum-graecum L. is traditionally used in medicine for diabetes, gout, hypertension, tuberculosis, bronchitis and cancer. Air pollution has persistently been the major cause of respiratory related illness and death. Environmental pollutants such as diesel and petrol exhaust nanoparticles (DEPs and PEPs) are the major contributors to urban air pollution. Lipid peroxidation and oxidative stress have been found to be the key mechanisms leading to the toxicity of these air pollutants. The current study was conducted to determine the ameliorating activity of Trigonella foenum-graecum L. against DEP/PEP induced invitro nanotoxicity. The experimental groups were exposed to DEPs/PEPs and were evaluated by biochemical end-points (LDH, NO, Total Proteins, SOD, GSH, MDA, H2O2, TNF-α, IL-6 and IL-8). Cytotoxicity of DEPs, PEPs and fenugreek leaf extract was determined by MTT assay in H9C2 (rat cardiomyocyte) cell lines. 24 hours exposure to DEPs / PEPs/ leaf extract resulted in dose‐dependent cytotoxicity in cultured H9C2 cells that were closely correlated with changes in biochemical parameters indicating oxidative stress and inflammation. Prior treatment with fenugreek leaf (Trigonella foenum-graecum L.) extract showed replenishment of antioxidant status and brought all values to near normal, indicating protection of cardiac cells from oxidative damage and inflammation by the anti-toxic and anti-oxidant effects of fenugreek leaf extract in cultured cell lines. Phytochemicals present in fenugreek could play an important role in ameliorating the DEP/ PEP induced toxicity.

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Study on the sorption kinetics and thermodynamics of Am(III) onto Attapulgite/Iron Oxide Magnetic Composites by linear and nonlinear methods

Yu T.

Attapulgite/Iron Oxide Magnetic Composites (ATP/IOMs) were prepared and characterized and the sorption behavior of Am(III) on ATP/IOMs was studied as a function of pH, ionic strength, the solid-to-liquid ratio (m/V), contact time and the concentration of Am(III) under ambient conditions using batch technique. Kinetic and thermodynamic studies of Am(III) sorption on ATP/IOMs were investigated by linear and nonlinear methods. Linear and nonlinear regression methods in selecting the optimum sorption isotherm were applied on the experimental data. The results indicated that the sorption can be described by a pseudo-second-order rate equation and the nonlinear pseudo-second-order kinetic expression could fit the kinetics better, compared to the linear forms. The nonlinear method is a better way to represent the sorption isotherm than the linear method and thus it should be primarily adopted to obtain the sorption isotherm parameters. Freundlich isotherm model is the best-fit model to the experimental data for the sorption. Nonlinear method is found to be the more appropriate method to determine kinetic and thermodynamic parameters.

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Comparative study of wet and dry process of cement manufacturing using Life Cycle Assessment approach

Boughrara S., Aksas H. and Louhab K.

The aim of this study is to evaluate or to assess the environmental impact of two kinds of cement Portland processes in the Algerian manufactories: that the first one- the dry process situated in a rural region (Sour El Ghozlane) and the second one-the wet process situated in an urban region (Rais Hamidou). To evaluate the potential impacts generated by these factories, the LCA approach is applied using the Simparo.7.1 software which shows several impacts assessed by EDIP 2003 in this study. A comparative study of impacts evaluated for those processes is made.

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Effect of cooling rate on properties of bovine and fish gelatin films fabricated by thermo-compression moulding technique

Chuaynukul K. and Prodpran T.

Effect of cooling rate (fast and slow cooling) on properties of compression-molded bovine and fish gelatin films molded at 120 and 140°C was investigated. Films prepared at moulding temperature of 140°C followed by fast cooling exhibited obvious shrinkage after conditioning at 25°C and 50% relative humidity while those obtained from other conditions showed negligible shrinkage. Generally, films with slow cooling rate had higher elongation at break (EAB) but slightly lower tensile strength (TS) and elastic modulus (EM) (p<0.05) compared to those obtained from fast cooling regardless of gelatin types and moulding temperatures used. Cooling rate showed no significant effect on water vapor permeability (WVP) and optical properties of resulting films (p>0.05).

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Effects of sulfur concentration and kinetics on heavy metal bioleaching from electroplating sludge using bubble column

Sundramurthy Venkatesa Prabhu and Rajoo Baskar

Electroplating sludge is classified as hazardous waste due to the heavy metal release into the environment. To leach heavy metals, bacterially assisted technique is an economical technology for treating the sludge. In this study, bioleaching of typical heavy metals (Zn, Ni and Cr) from the sludge generated at the metal finishing plant has been investigated using sulfur-grown Acidithiobacillus ferrooxidans. Experiments were carried out using bubble columns with 1 L/min of air flow rate and the effect of sulfur concentration (2–10 g/L) has been studied. For 50 g/L sludge loading, results have shown that maximum of 97.96% Zn, 78.83% Ni and 89.65% Cr were leached out at 6 g/L sulfur concentration. The kinetic study on bioleaching data showed that the rates of heavy metal bioleaching were relatively high at optimum sulfur concentration which were 0.0082, 0.0034 and 0.005 h1 for Zn, Ni and Cr respectively. The kinetics of shrinking core model on leaching data explicated that chemical reaction is the rate-controlling step of heavy metal bioleaching which controls the rate of heavy metal biosolubilization.

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Reproductive health effects of contemporary pesticides used in South Africa

Dalvie M. A.

A review of male reproductive health effects due to hormonally active contemporary pesticides used in South African agriculture was conducted. The objective was to examine and present evidence in order to evaluate the need for research in this area especially in the Western Cape, a major agricultural area in South Africa. The review identified a number of contemporary-used agricultural pesticides that have been shown to induce in vitro endocrine activity and that have been shown to affect gonadotrophin hormone release as well as adverse reproductive development in animals and humans. Rural residents in the Western Cape, South Africa are environmentally exposed to pesticides.

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New Generation or Perspective Ecofriendly Adsorbents for Future Emergency Water Purification

Chmielewská Eva

In this review paper some attention is focused on the various traditional and ecofriendly adsorbents, a few of the local repositories which prove enhanced performance for environmental pollutants removal. Due to their low cost and local availability, natural materials such as zeolite, montmorillonite-rich bentonite, industrial waste product chezacarb, beringite, chitosan, low rank coal shungite, fossil alginite, slovakite, starch, peat, commercial-grade active coke and iron oxyhydroxides GEH were chosen to evaluate their adsorption performance in selected pollutant removal.

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