Research Journal of Chemistry and Environment

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Research Journal of Chemistry and Environment

Thermal, Structural and Optical Analyses of Benzimidazole Single Crystal Grown with Organic Dopants for Nonlinear Optical Applications

Vijayan N.,1* Madhurambal G.,2 Bhagavannarayana G.1, Maurya K. K.1 and Mojumdar S. C.3, 4

Nowadays nonlinear optical (NLO) materials are gaining attention because of their numerous applications in the area of fibre optic communication and optical signal processing. In the present study, the nonlinear optical material of benzimidazole (BMZ) has been grown by slow evaporation solution growth technique using two different organic dopants (Urea and N-methyl urea) at different molar percentages. The effect of dopants on the growth and other physical properties has been analyzed by different instrumentation methods. The addition of urea and N-methyl urea (NMU) to the host material of benzimidazole has not changed the existing crystalline system, but there was a trivial variation in the lattice dimensions which is confirmed by powder X-ray diffraction analysis. The crystalline perfection was analyzed by high resolution X-ray diffraction analysis. It was found that urea dopant enhances the crystalline perfection in comparison with the N-methyl urea, which is in tune with the scanning electron microscopic analysis. The thermal performance has been examined by TG-DTA for all the doped specimens. Its relative second harmonic generation efficiency was evaluated by Kurtz powder technique and it was found that the doped specimens showed enhanced efficiency in comparison with the pure benzimidazole. Its optical properties have been examined by UV-VIS spectral analysis and found variations in the observed transmittance values were found.

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Neutralization of Red Mud using Inorganic Acids

Rai S.B.,1 Wasewar K.L.,2,3* Mishra R. S.,1 Puttewar S. P.1 and Chaddha M. J.,1 Mukhopadhyay J.1 and Chang Kyoo Yoo3*

Red mud’ or ‘bauxite residue’ is a waste generated from alumina refinery in an enormous quantity posing a very serious and alarming environmental problem due to its high causticity. Red mud is highly alkaline in nature with a pH of 10.5-12.5 due to caustic soda solution used in extraction of alumina from bauxite ore using Bayer process. It can be made less hazardous and capable for utilization by ameliorating the caustic properties of red mud. One of the options may be neutralization of red mud using inorganic acid. To see the feasibility of using acid for the treatment of red mud, a systematic, methodological and comparative study of pH was carried out using three different inorganic acids (HCl, H2SO4, HNO3) for neutralizing red mud from two different Indian alumina refineries having different composition. The work describes the chemical characterization of red mud before and after neutralization at different pH values with all the three acids. Parameters such as weight of red mud and volume of acid are optimized. Phases of different constituents in neutralized red mud have also been studied. It has been observed that nearly 35- 40% of the total caustic soda can be reduced by acid treatment.

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Scaling up of poly (3-hydroxybutyrate) production from oil palm frond juice by Cupriavidus necator (CCUG52238T)

Zahari M.A.K.M.

It has been reported that oil palm frond juice (OPF) can be used as the sole renewable, alternative and cheap carbon source for the production of poly(3-hydroxybutyrate), P(3HB) at lab scale study. In order to further investigate the potential of OPF juice for P(3HB) production at larger scale, we scaled up the fermentation process from 500 ml shake flask to 20 L bioreactor based on constant volumetric mass transfer coefficient (kLa) of oxygen at both scale. It was interesting to note that the P(3HB) content obtained in this study was almost similar as reported in the previous study both in shake flask and 2 L bioreactor. The P(3HB) content for shake flask fermentation was 45 wt.%, while 44 wt.% and 42 wt.% in 2 L and 20 L bioreactor respectively. Based on the current finding, it can be concluded that the scaling up method based on constant kLa was successful due to the almost similar P(3HB) content obtained in shake flask and bioreactor scale. Overall, it can be postulated that OPF juice can be successfully used as a non-food fermentation feedstock for the production of P(3HB) both in small and large scale fermentation.

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Natural pigment production by Thermomyces sp using response surface methodology

Poorniammal R., * Gunasekaran S. and Murugesan R.

The Central composite design involving the variables pH (X1), incubation temperature (X2) and fermentation time (X3), a response surface methodology for the production of yellow pigment by Thermomyces sp was standardized. Data analyzed using a second order polynomial equation resulted in the optimized process condition of 135 h growth at 30.17°C in a czapek yeast extract medium of pH 8.14 for pigment production. Under these conditions the model predicted 781 OD units of yellow Pigments which are 25 % higher than the initial medium. With regard to biomass, 2.60 g dry weight/100 ml culture medium was obtained after 144 h of growth at 30.160C in the medium of pH-8.22.

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Sodium Dodecyl Benzene Sulfonate (SDBS) degradation by heterogeneous Fenton-like reactions on two types of catalysts: experimental and comparison

Zhang Ting

Two kinds of attapulgite(ATP)-based catalysts were prepared by incipient wetness technique (the samples were represented by Fe(III)/ATP) and mixing method(the samples were represented by Fe2O3/ATP) separately. Their heterogeneous Fenton-like reactions were investigated for the degradation of Sodium dodecyl benzene sulfonate(SDBS) and contrasted with Fe2O3/H2O2 system. The physicochemical characteri-stics of the two synthesized samples were evaluated by various techniques such as XRD, SEM, FT-IR. Compared with the Fe2O3 catalyst, the two new ATP-based catalysts exhibited a higher activity and stability in SDBS mineralization. Fe (III)/ATP and Fe2O3/ATP had high catalytic reactivity at a wider pH range and repeating usage. Furthermore, an enhancement of H2O2 utilization ratio was also achieved. When introducing ATP to Fe2O3, the degradation ratios of the catalysts were greatly enhanced because.

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Biodegradation of chlorobenzene and chlorophenols by Pseudomonas cultures

Gaikwad Bhaskar G.* and Varma Rita J.

Cultures from NCIM culture collection (National Chemical Laboratory, Pune, India) were screened for biodegradation chlorobenzene (CB). A strain, Pseudomonas sp. NCIM 2303, was found to be most effective. The biodegradation was carried out in aqueous solution by resting cells. The decomposition of 0.02% CB was 96.64% in 24h. We have screened cultures for biodegradation of o-chlorophenol and p-chlorophenol. Pseudomonas sp. NCIM 2668 has shown 94.59% degradation of 0.15% o-chlorophenol. Pseudomonas sp. NCIM 2668 has shown 31.42% degradation of 0.2% p-chlorophenol.

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Effects of Solution Chemistry on the Flotation of Magnesite, Dolomite and Quartz with Sodium Oleate as a Collector using SEM Analysis

Yao Jin*, Yin Wanzhong, and Hou Ying

In this study, the floatability of magnesite, dolomite and quartz with different pH value and the effects of regulators sodium silicate and sodium hexametaphosphate on those three minerals in sodium oleate flotation system were tested. Furthermore, the interactive effects between these minerals were researched including the influences of dolomite and quartz on the floatability of magnesite, the influence of dolomite on the floatability of quartz and the influence of dolomite on the floatability of the mixture of magnesite and quartz. Mechanisms have been discussed in association with solution chemistry calculation, zeta potential measurement and SEM analysis. The results show that the floatability of magnesite and dolomite was good and sodium hexametaphosphate and sodium silicate could suppress the floatation of magnesite and dolomite. Moreover, these three minerals have interactive effects on each other. Adding dolomite or quartz could decrease the magnesite recovery and adding dolomite could improve the quartz recovery which was mainly caused by the ions in mineral solutions and the adsorption of fine particles on coarse particles.

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A Study on Chemical Leaching of Iron from Red mud using Sulphuric Acid

Das Debadatta and Pramanik K *

Huge quantity of red mud is generated each year as a waste by the alumina industry which consists of a large percentage of iron oxide. This can be recovered and reused if an effective method is exploited. The present work aims at the extraction of iron from red mud by acid leaching using H2SO4. Various process parameters such as temperature, time of contact, proportion of solid to liquid and concentration of acids were investigated through regression analysis to determine their effects on iron leaching and establish optimum leaching conditions. The leaching result showed 47% iron recovered from red mud under optimum condition of 1000C, 24 hours, 8N acid concentration and 5: 100 solid to liquid ratio.

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Impact of Raw Coolant Wastewater and Effluent from different stages of treatment on Fish Lebistes-reticulatus (Peter)

Satyanarayan S.,1 Satyanarayan A.2 and Verma S.3*

Bioassay test was performed using fish Lebistes-reticulatus to study the toxic effect of coolant water. Results showed that raw coolant wastewater depicts severe toxicity compared to physico-chemical treated effluents. After oil removal from the raw coolant wastewater, the fish toxicity reduced by 20-24% while treated effluent from settling tank after flash mixing with alum, alkali and acid, depicted 90-96% less toxicity. Effluent from polishing pond showed no toxicity towards the fish even after one month long exposure. This study discusses in detail the treatment provided to the coolant wastewater and toxicity evaluation of treated effluents from different stages of treatment.

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An efficient synthesis of tetrahydrocarbazole using solid acid catalyst

Majid Sheikh Abdul*, Khanday Waheed Ahmad and Tomar Radha

MCM-22 zeolite was synthesized by two different methods under static hydrothermal conditions having different silica and aluminum sources. The materials were characterized by BET surface area, X-Ray Diffraction, Scanning Electron Microscope, Energy-dispersive X-ray spectroscopy analysis, NH3-Thermal Programming Desorption and Fourier Transform Infrared Spectroscopy. Synthesis of 1,2,3,4- tetrahydrocarbazole (THC) has been carried out over synthesized MCM-22a and b by Fisher’s method using phenylhydrazine cyclohexanone, cyclo-pentanone as reactant and methanol as solvent. The catalytic efficiency of MCM-22a was greater than MCM-22b as its pore size and surface area is high as compared to other.

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Seasonal Variation in physico-chemical parameters and Heavy Metals Assessment in Surface Water of North Alabama

Okweye P.S.

Water quality in North Alabama is becoming a critical issue and in order to understand the quality of water in the Flint Creek and Flint Rivers, concentration levels of physicochemical parameters and trace heavy metals were measured in six strategically selected sites within the streams to obtain baseline data. A total of 192 surface water samples were collected and analyzed for total phosphorous and five heavy metals of concern. Physical and chemical parameters were determined for dissolved oxygen (DO), turbidity, pH, temperature, water conductivity and total phos- phorous. The concentration of the DO was above guidelines in three sites at both rivers. All metals were statistically significant (P ≤ 0.05) at 95% confidence interval by watershed. Aluminum and lead exceeded their maximum permissible levels. The results for heavy metals in this study show location and seasonal variability. There was significantly higher heavy metal content during winter>spring>summer>fall. The values for the Hazard Quotientand Hazard Index for both watershed sites were mostly more than 1, indicating some levels of concern. Additionally, surrounding rocks and other anthropogenic sources appeared to be causing the elevated chemical content of the rivers and may have resulted in significant adverse impacts on the study areas.

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