Research Journal of Chemistry and Environment

Indexed in SCOPUS, Chemical Abstracts Services, UGC, NAAS and Indian Citation Index etc.

Research Journal of Chemistry and Environment

Effects of low molecule weight organic acids on Cd solubility in paddy and red soils in South China

Ding Yongzhen, Tang Shirong, Li Zhian and McBride Murray

Batch experiments of Cd adsorption and Cd desorption were conducted to study the effects of low-molecule-weight organic acids (LMWOAs) on Cd solubility in paddy and red soils in south China. Cadmium solubility was highly pH dependent. As pH increased from 2 to 8, Cd solubility decreased in the presence of fumaric, oxalic, tartaric and malic acids. Citric acid showed very different behavior causing Cd solubility to reach a minimum at an intermediate pH of 4-5. At low pH, increasing citric, oxalic or malic acid concentrations resulted in a decrease in Cd solubility, whereas fumaric and tartaric acids had little effect. At high pH, citric acid increased Cd solubility dramatically even at the lowest concentration (0.5 mmol L-1). Other acids had little effect except that fumaric and oxalic acids increased Cd solubility slightly in red soil with concentrations above 5.0 mmol L-1. Overall, the effects of LMWOAs on Cd solubility were small, but oxalic and citric acid strongly influenced solubility at low and high pH respectively. Among the LMWOAs, those with higher stability constants for Cd-LMWOA complexes and weak tendency to adsorb on soils had maximum ability to solubilize Cd. Higher Cd solubility was observed in red soil compared to paddy soil due to lower pH, CEC and clay content of the red soil.

Full Text

Studying Solubility of Biodegradable Films prepared from Collagen Hydrolysate

Mokrejs P., Janacova D., Mladek M., Langmaier F., Kolomaznik K. and Vasek V.

Biodegradable films were prepared by casting from 50 % solution of hydrolysate (w/w) cross-linked with starch dialdehyde (DAS). DAS was dosed 0, 2, 4, 6, 8 and 10 % based on weight of hydrolysate. 30 g of hydrolysate were dissolved in 100 ml of water at 60 oC and after adjustment of pH to 11 with 1 N NaOH, starch dialdehyde was added. The solution was cast on a silicone plate and the film was made after evaporation of water at 30 oC for 72 hours. Test film samples measuring 2 by 2 cm were cut and conditioned over silica gel in a dessicator for 2 and/or for 15 days. Solubility tests were conducted in glass bottles where test film samples were covered with water and incubated at 37 oC for a desired period of time. After the prescribed dissolution time, the non-dissolved fraction of the test film sample was separated by filtration, dried at 103 oC to a constant weight and weighed. The dependences of dissolved film sample fractions on time of dissolution with various amounts of DAS, are presented graphically. It was found that the higher is dosage of DAS, the lower is solubility of films. A longer conditioning time also showed a lower dissolving rate of films. Solubility curves of biodegradable films are very important characteristics for their utilization in practice.

Full Text

Arsenic Removal Household Filter for Small Community

Maji Sanjoy Kumar, Pal Anjali and Pal Tarasankar

Natural adsorbent, laterite soil was selected and found to be an effective adsorbent for arsenic removal from arsenic bearing drinking water. The real arsenic bearing groundwater was collected from Nivedita Palli, 24 Paraganas, one of the arsenic affected areas of West Bengal. It was found that 20 g/L dose of the adsorbent removes ~98% of total arsenic from real arsenic bearing groundwater when the initial concentration was 0.33 mg/L with an agitation time and speed of 30 min and 170 rpm respectively. Isotherm study suggests that the removal capacity (0.18 mg/g) of the adsorbent is comparable with other natural adsorbents. Fixed bed column study was conducted to evaluate the column performance with the synthetic (using 20 cm bed depth) as well as real (using 10 cm bed depth) arsenic bearing groundwater samples. The fixed bed was designed by logit model. The values of adsorption rate constant (K) and adsorption capacity (No) were obtained as 0.3134, 0.7208, 1.21 L/(mg h) and 132.23, 70.81, and 69.22 mg/L for the minimum bed depth 13.89, 11.28 and 6.12 cm respectively for As(III) and As(V) and real sample. To get arsenic free water a domestic household filter “SANTA-2006”was designed with an earthen pitcher (kolsi). After continuous passing of 200.0 L of real sample of arsenic contaminated water under gravity, the breakthrough comes. The effluent water quality was tested. The results suggest that quality of water is acceptable for drinking purpose.

Full Text

Effects of Simulated Acid Rain on Disturbed, Rehabilitated and Mature Forest Soil of Lower Subtropic China: Leaching Experiment

Liu K.H., Yu F.M. and Peng S.L.

An evaluation of response of one disturbed, one rehabilitated and one mature forest soil in lower subtropic China to simulated acid rain (SAR) (pH = 4.5, 3.5 with three ions concentration levels, and using distilled water, pH=6.5 as control) were studied using a controlled laboratory leaching experiment. Land-use change is one of the important factors in controlling soil response to acid deposition. Effects of SAR on leachate pH, electrical conductivity (EC), base cations and its adsorpted values by soil were studied in these soils. The results showed that (1) the decrease extent of leachate pH and EC were more intensive in PMF than that in PBMF and MEBF. There was significant relationship between leachate pH and EC (Y = -309+1377*X, R = -0.81, P < 0.001, N = 252); (2) Leachate ion trend was not always having the same leaching dynamics in each forest soil. The concentrations of univalent cations decreased with treatment time during the study period, while the concentrations of bivalent cations increased in the later leaching period (except Ca2+ in PBMF); (3) Soil base cations showed negative adsorption in PMF, while the opposite occurred in PBMF and MEBF; (4) Ionic strength played a more importhant role on leachate’s content than acid strength; (5) As in the same forest soil, there were no significant differences between treatments in this study that might be the reason of extremly acidity soil and comparable short treatment time.

Full Text

High Turbidity Removal by Magnetite Particles

Shang-Lien Lo, Yung-Li Wang and Ching-Yao Hu

The high turbidity raw water during the rainstorm period has made the water treatment plants fail to supply applicative water in recent years. How to improve the treating capacity of water treatment plants is an important issue at present. In this study, high turbidity raw water was effectively treated by magnetite (Fe3O4) particles. After magnetization, magnetite particles can reduce turbidity from 9,600 NTU to 20 NTU. Furthermore, magnetite particles are suitable for the pH ranges of drinking water from pH=6.0 to pH=9.0 and an external magnetic field applied during sedimentation increases the removal rate. In addition, the recycle and reuse of magnetite particles were investigated. Magnetite particles were successfully regenerated by cetyltrimethyl ammonium bromide (CTAB) and the effective used times of magnetite particles was five times.

Full Text

Hydrolysis Activity of Mutants of F1-ATPase: A Comparative Study using Spectrophotometric Method

Hossain Mohammad Delawar

Biological cells contain ATP synthase that makes ATP. F1-ATPase is the water soluble portion of ATP synthase that acts as an ATP-hydrolysis driven rotary molecular motor. Previously we studied ATP hydrolysis activity as well as generation of torque by some mutants of F1-ATPase in which 14, 17 or 21 amino acid residues at the carboxy terminus of the g subunit were absent1. It has been found that the mutant made by deletion of 21 amino acid residues could produce about half of the torque of another mutant that lacks 14 amino acid residues or wild type but it showed poor ATP hydrolysis activity. In this paper, the rate of ATP hydrolysis by these mutants was compared using spectro-photometric method. It was found that the mutant lacking 14 amino acid residues was activated that was recognized by a well defined peak in the activation profile whereas the mutant lacking 21 amino acid residues was deactivated indicating its structural instability.

Full Text

Determination of Tenofovir in Pharmaceutical Formulation by Zero Order and First Order Derivative UV-Spectrophotometry Methods

Shirkhedkar Atul A., Bhirud Charushila H. and Surana Sanjay J.

Two simple, rapid, accurate and economical ‘Zero order UV- spectrophotometry’ and ‘First order derivative’ methods have been developed for estimation of tenofovir in bulk and tablets. In double reverse osmosis water, the l max of tenofovir was found to be 260 nm and the same spectrum was derivatised into first order derivative using UV probe software of UV-spectrophotometer (Shimadzu 2450), at Dl = 4. The amplitude of the trough was recorded at 273 nm. In both the proposed methods, linearity was observed in the concentration range of 5 – 40 µg/ml. The assay results were in good agreement with label claim. The methods were validated statistically and recovery studies.

Full Text

Aniline Biodegradation in Riverbed Sediments with Low Concent of Organic Carbon under Denitrification Conditions

Yaoguo Wu, De-Zhong Yin and Yun-Feng Li

The riverbed sediments (collected from Weihe River, close to Xi’an, China) treated with chemical sequential extraction procedures as well as groundwater (from a 20m-depth well in Xi’an) are used in the microcosms tests to research the characteristics of aniline biodegradation in the riverbed sediments with low content of organic carbons (SLC) under denitrification conditions. The results show that aniline can be degraded in SLC under denitrification conditions. It takes about 20d, 45d and 70d to degrade (about 50mg/L) aniline 95%, when the intinal concentration of nitrate is 30.69 mg/L, 184.16 mg/L and 245.54 mg/L respectively. But, when 35.98 mg/L acetate is added as external organic matter to the microcosm, and the intinal concentration of nitrate is 184.16 mg/L, aniline is degraded quicker than that when nitrate is 30.69 mg/L or 245.54 mg/L. Compared the rates of aniline degradation in the microcosms without and with (35.98 mg/L) acetate added aniline is degraded faster in the microcosms without acetate than that in the microcosms with acetate added. So the external matters have a potential to inhibit the degradation of aniline under these conditions. However, when the concentration of nitrate is 184.16 mg/L or 245.54 mg/L, the external matters have a potential to enhance the degradation. Hydrous metal oxides accelerate the degradation of aniline in SLC under denitrification conditions.

Full Text

Spectrophotometric Determination of Microgram Quantities of Palladium (Ii) in Alloys

Pape Gowd C.T. , Srinivas J. and Rao Suryanarayana V.

A method for the spectrophotometric determination of Pd(II) has been developed by using furfuraldehyde thiosemicarbazone (FFTSC) as complexing agent. Pd(II) reacts with FFTSC in the pH range 1 to 5 to form yellow coloured solution. The complex shows maximum absorption in a buffer solution of pH 1. lmax is 360.5nm. The composition of the complex is 1:4(M:L). Beer’s law is obeyed in the range 0.170 mg/ml to 1.703 mg/ml. The molar absorptivity and Sandel sensitivity are calculated as 3.9911X104 L mol-1 cm-1 and 0.0026664 mg cm-2 respectively. The method has been successfully applied for Pd(II) determination in alloys.

Full Text

Photocatalytic Oxidation of Arabinose and Glucose over Cadmium Sulphide

Jain Sangeeta and Ameta Suresh C.

The photocatalytic oxidation of arabinose and glucose on cadmium sulphide was carried out and the progress of reaction was monitored spectrophotometrically. The effect of the variation of various parameters such as pH, concentration, amount of cadmium sulphide, light intensity, etc. on this photocatalytic oxidation was observed.A tentative mechanism for this degradation has also been proposed.

Full Text

Assessment of Water Quality of Godavari River at Nanded, Maharastra and Rajahmundry, Andhra Pradesh, India

Srinivasarao V., Khan A.M., Murthy Y.L.N., Viplavaprasad U. and Machiraju P.V.S.

This paper represents the result of chemical characteristics such as Dissolved Oxygen, Biochemical Oxygen demand, and Chemical Oxygen demand during one year at Nanded (Maharashtra) and Rajahmundry (A.P). It was observed that Godavari River at Nanded was more polluted than Rajahmundry.

Full Text

Degradation of Thiocyanate from Aqueous Waste by a Mixed Bacterial Community

Patil Yogesh B.

Aqueous wastes containing thiocyanate (SCN-) are frequently encountered from variety of industrial processes. If improperly managed, these wastes can cause reversible or irreversible impact on the soil and water environment. In the process of developing a microbial technology for the SCN- removal from aqueous waste, heterotrophic bacterial consortium’s capable of degrading the SCN- compound were isolated by an enrichment culture technique from activated sludge and garden soil. All the isolated cultures were Gram negative and motile. Bacterial community isolated from activated sludge was found to be more efficient. Experiments performed under standardised laboratory conditions revealed that biodegradation of SCN- (50 mg/l) by microbial community isolated from activated sludge occurred within 24 h with an efficiency of >99.9 % at pH 7.0, temperature 30°C, glucose 5 mM and initial cell density of 108 cells/ml.

Full Text

Adsorption of Hg (II) Ions from Water by Activated Carbons

Goyal Meenakshi and Amutha R.

The adsorption isotherms of Hg (II) ions from aqueous solutions have been studied on three granulated activated carbons and a sample of activated carbon cloth. The adsorption data obeys both the Langmuir and Freundlich isotherm equations. The xm value obtained from the linear Langmuir plots has been used to determine the fraction of the carbon surface occupied by the Hg (II) ions while the linear Freundlich plot constant n has been used to look at the heterogeneity of the carbon surface. The adsorption takes place on certain specific sites on the carbon surface and only a fraction of the BET surface area is occupied by the Hg (II) ions. The adsorption is determined by the amount of acidic carbon – oxygen surface groups present on the carbon surface. It increases with increase in the amount of these surface groups on oxidation and decreases when these surface groups are eliminated on degassing of the oxidized carbon. The adsorption involves attractive electrostatic interactions between the negative sites created by the ionization of the acidic carbon - oxygen surface groups and the positively charged Hg (II) cations.

Full Text

Influence of Cl– and SO4–2 ions on the Corrosion Behaviour of ZA-27 alloy

Pruthviraj R.D.

The effects of anions like Cl– and SO42– on the anodic dissolution of the monolithic ZA-27 alloy have been investigated at neutral pH through immersion testing and electrochemical techniques like potentiodynamic polarization techniques. Scanning electron microscopy was employed to characterize the corroded surface and to observe the extent of pitting in different media. From the evaluated corrosion parameters it was found that the dissolution of the matrix was extensively reduced in presence of aqueous solutions containing SO42– ions while Cl– ions aggravated corrosion by penetrating into the barrier oxide film on the surface of the material. Pronounced effect of pitting was observed in presence of Cl–. Corrosion rates were, however, controlled during prolonged exposure in the electrolytic media, specially in case of chloride media, due to the predominance of film repair kinetics.

Full Text

Synthesis, Characterisation and Antimicrobial Activities of Co(II), Ni(II), and Cu(II) Complexes of Hexamethylenetetramine Ligand

Agwara M.O., Ndifon P.T., Ndikontar M.K. and Atamba M.A.

Hexamethylenetetramine (HMTA, C6H12N4) complexes of Co(II), Ni(II), and Cu(II) have been synthesized in ethanol. While the cobalt(II) and copper(II) complexes have one molecule of hexamethylenetetramine, the nickel complex has two molecules. These complexes have been characterised by elemental analyses, infrared and visible spectroscopy, 1H NMR, conductivity and room temperature magnetic susceptibility measurements. The results suggest octahedral coordination in which the central metal ion is bonded to HMTA and aqua ligands. Antimicrobial activities of the ligand and its derived complexes show that the ligand, HMTA is active against 2 out of 11 tested organisms; the nickel complex [Ni(H2O)4(HMTA)2]Cl2.5H2O is active on none and the cobalt complex is active against 4 of the organisms. The copper complex, [(CuCl2)2 (HMTA)(H2O)2] is active against all the 11 tested organisms, including the yeast, Candida albicans.

Full Text

E-Waste Recycling-Best Option for Resource Recovery and Sustainable Environment

Parthasarathy P. , Keshav A. Bulbule and Anantha Murthy K.S.

Bangalore figures prominently in the world map for its contribution in Information Technology (IT), Business Process Outsourcing, Research and Development ( R&D) outsourcing and Bio-Technology. This phenomenal growth over the past decade, has given rise to the generation of lot of Electronic Waste. E-waste thus generated contains many recoverable metals and non metals along with hazardous wastes and their improper disposal may cause environmental problems. The main issue of E-Waste is that there are backyard recyclers who are practicing E-waste recycling by adopting crude methods resulting in inefficient recovery, besides causing health and environmental hazards.

Full Text

Nuclear Overhauser Effect : Revolutionary Approach in NMR Spectroscopy

Upmanyu Neeraj, Dolly Archana, Garg Gopal and Mishra Pradeep

Nuclear overhauser effect (NOE) is the change in a signal’s intensity as the result of perturbation applied to spins other than those associated with that signal. NOE, is therefore, the effect of magnetization transfer through space. NMR is commonly used for characterizing the structure and molecular dynamics of target or ligand molecules. NOE is used for the identification of lead compounds in an NMR screening, preferably in a high throughput manner. Reverse NOE pumping and transferred NOE can be used without isotope labelled protein. Sequential NOE connectivity determines the secondary structure elements. The three-dimensional structure is from NOE connectivity’s between secondary structure elements. NOE-based methods not only prove ligand-protein binding interactions, but they can, in addition be used to characterize the binding epitope of the ligand.

Full Text