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CONTENTS
Volume 2, Number 4, December 2013
 

Abstract
The degradation of alachlor has been investigated using sonolysis (US), photocatalysis (UV) and sonophotocatalysis (US/UV) using three photocatalyst viz. TiO2 (mixture of anatase and rutile), TiO2 (anatase) and ZnO. The effect of photocatalyst loading on the extent of degradation of alachlor has been investigated by varying TiO2 (both types) loading over the range of 0.01 g/L to 0.1 g/L and ZnO loading over the range of 0.05 g/L to 0.3 g/L. The optimum loading of the catalyst was found to be dependent on the type of operation i.e., photocatalysis alone or the combined operation of sonolysis and photocatalysis. All the combined processes gave complete degradation of alachlor with maximum rate of degradation being obtained in the case of sonophotocatalytic process also showing synergistic effect at optimized loading of photocatalyst. About 50% to 60% reduction in TOC has been obtained using the combined process of sonophotocatalysis depending on the operating conditions. The alachlor degradation fitted first order kinetics for all the processes under investigation. It has been observed that the TiO2 (mixtrure of anatase and rutile) is the most active photocatalyst among the three photocatalysts studied in the current work. The effect of addition of radical enhancers and scavengers on sonophotocatalytic degradation of alachlor has been investigated in order to decipher the controlling mechanism. The alachlor degradation products have been identified using LC-MS method.

Key Words
alachlor degradation; sonophotocatalysis; photocatalysis; ultrasound; process intensification

Address
Manisha V. Bagal and Parag R. Gogate: Chemical Engineering Department, Institute of Chemical Technology, Matunga, Mumbai-40019, India.

Abstract
In this study, a comprehensive model developed to estimate greenhouse gas (GHG) emissions from urban area with low impact development (LID) and its integrated management practices (IMPs). The model was applied to the actual urban area in Asan Tangjeong district (ATD) as a case study. A rainwater tank (1200 ton) among various LID IMPs generated the highest amount of GHG emissions (3.77

Key Words
greenhouse gas emission; low impact development; green infrastructure; life cycle assessment; reduction effect; sensitivity analysis

Address
(1) Dongwook Kim, Taehyung Park and Woojin Lee: Department of Civil and Environmental Engineering, Korea Advanced Institute of Science & Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea;
(2) Kyounghak Hyun: Korea Land & Housing Corporation Institute, 539 Expo-ro, Yuseong-gu, Daejeon 305-731, Republic of Korea.

Abstract
In the present study, an experimental design methodology was used to optimize the adsorptive removal of Basic Yellow 13 (BY13) using Turkish coal powder. A central composite design (CCD) consisting of 31 experiments was employed to evaluate the simple and combined effects of the four independent variables, initial dye concentration (mg/L), adsorbent dosage (g/L), temperature (°C) and contact time (min) on the color removal (CR) efficiency (%) and optimizing the process response. Analysis of variance (ANOVA) showed a high coefficient of determination value (R2 = 0.947) and satisfactory prediction of the polynomial regression model was derived. Results indicated that the CR efficiency was not significantly affected by temperature in the range of 12-60°C. While all other variables significantly influenced response. The highest CR (95.14%), estimated by multivariate experimental design, was found at the optimal experimental conditions of initial dye concentration 30 mg/L, adsorbent dosage 1.5 g/L, temperature 25°C and contact time 10 min.

Key Words
adsorption; coal; organic dye; experimental design; optimization

Address
(1) Alireza Khataee and Leila Alidokht: Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran;
(2) Leila Alidokht: Department of Soil Science, Faculty of Agriculture, University of Tabriz, Tabriz, Iran;
(3) Aydin Hassani and Semra Karaca: Department of Chemistry, Faculty of Science, Ataturk University, 25240 Erzurum, Turkey.

Abstract
A new high capacity sorbent for preconcentration and determination of nickel in environmental samples was synthesized. The sorbent was synthesized by copolymerization of allyl glaycidyl ether / imminodiacetic acid with N,N-dimethylacrylamide as functional monomers in the presence of N,N-bismethylenacryl amid as cross linker and characterized by Fourier transform infra red spectroscopy, elemental analysis, thermogravimetric analysis and scanning electron microscopy. A recovery of 93.6% was obtained for the metal ion with 0.1 M, sulfuric acid as the eluting agent. The sorption capacity of the functionalized sorbent was 55.9 mg g-1. The equilibrium sorption data of Ni(II) on polymeric sorbent were analyzed using Langmuir, Freundlich, Temkin and Redlich.Peterson models. Based on equilibrium adsorption data the Langmuir, Freundlich and Temkin constants were determined 0.87 (L mg-1), 25.87 (mg g-1) (L mg-1)1/n and 171.4 (J mol-1) respectively at pH 4.5 and 20

Key Words
high capacity sorbent; nickel; preconcentration; isotherm study

Address
(1) Homayon Ahmad Panahi, Alireza Feizbakhsh and Fatemeh Dadjoo: Department of Chemistry, Islamic Azad University, Central Tehran Branch, Iran;
(2) Elham Moniri: Department of Chemistry, Islamic Azad University, Varamin (Pishva) Branch, Iran.


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