VOLUME 39, NO5, OCT-2017
123
 
Degradation of Cytotoxic Agent in Soap and Detergent Wastewater by Advanced Oxidation Processes

Munawar Iqbal, Ijaz Ahmad Bhatti, Jan Nisar and Mazhar Abbas

Wastewater from soap and detergent industries is a source of high pollution and contamination for water sheds. In present investigation, cytotoxic profiling was documented from Faisalabad, Sargodha and Gujranwala cities, Pakistan, followed by advanced oxidation processes (AOPs) treatments (UV and gamma radiation). The cytotoxicity was evaluated by Allium cepa, haemolytic and brine shrimp bioassays. Independent variables such as gamma radiation absorbed dose, H2O2, TiO2 concentrations, reaction time, pH and shaking speed were optimized using statistical techniques. The raw soap and detergent wastewater showed cytotoxicity up to high extent. At optimized conditions, > 94% degradation was achieved both in case of UV (exposure time 100 min, TiO2 concentration 5.93 g/L, H2O2 4.39%, pH 6.50 and shaking speed 110 rpm) and gamma radiation (12.69 kGy absorbed dose in the presence of 4.65% H2O2) treated samples and water quality parameters (WQP) also improved significantly. The cytotoxicity reduced sharply as a result of AOPs treatment at optimized conditions. From the results, it is evident that AOPs under investigation could be used for the degradation and cytotoxicity reduction of soap and detergent wastewater.
Pages(706)
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UV Radiations Assisted Advanced Oxidation Approach for the Degradation of Reactive Azo Dye, Using TiO2 Photocatalyst

Ijaz Ahmad Bhatti, Misbah and Saira Irshad

About 10,000 tons of different reactive dyes are produced every year all over the world. A huge amount of these dyes is discharged out into water bodies as textile effluents causing environmental hazards. It is necessary to eliminate such persistent contaminants from environment. In present project, solution of reactive azo dye was irradiated which resulted in the free radical degradation known as radiolysis. For the treatment of dye solution, variable parameters such as pH, concentration of H2O2, concentration of TiO2, time of UV irradiation was optimized for the achievement of higher degradation rate of dyes. The response surface methodology (RSM)) was applied for theoretical optimization and collected data interpretation. UV/Visible and FT-IR (Fourier Transform Infrared) spectroscopic techniques were employed for the analysis of extent of dye degradation. The optimized conditions can be employed for the treatment of textile industry wastewater on pilot scale. This heterogeneous photo catalytic method has been found an economical and efficient way for the advanced oxidation treatment of textile industry waste water. The treated water can be reused for industrial and agricultural purposes.
Pages(718)
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Synthesis and Structural Properties of N-(2-bromo-4-nitrophenyl)-3-methoxy-4-oxo-3,4-dihydro-2H-benzo[e][1,2]thiazine-3-carboxamide 1,1-dioxide: A Comparative Experimental and Quantum Chemical Study

Muhammad Nadeem Arshad, Naveen Kosar, Adullah Muhammad Asiri, Khurshid Ayub Islam Ullah Khan and Tariq Mahmood

N-(2-bromo-4-nitrophenyl)-3-methoxy-4-oxo-3,4-dihydro-2H-benzo[e][1,2]thiazine-3-carboxamide-1,1-dioxide was synthesized in three step process with 86 % overall yield. The final structure of compound was evaluated by using spectroscoanalytical methods (1H-NMR and FT-IR). Suitable crystals were obtained by slow evaporation method, and the final structure was confirmed unequivocally by performing single crystal X-ray diffraction (XRD) studies. Geometric parameters were calculated at B3LYP/6-31G (d, p) method with the help of Gaussian 09 software to validate spectrosopic and single crystal X-ray results. The computed data corroborated nicely with the experimental results (spectroscopic and X-ray). Frontier molecular orbitals (FMOs) and reactivity indices revealed the reactivity of benzothiazine derivative. Molecular electrostatic potential (MEP) was measured to understand the electro or nucleophilic nature of compound. Mulliken and natural population charge analysis (NBO) was carried out to prove inter and intramolecular hydrogen bonding.
Pages(727)
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The Comparison of Mechanical and Thermal Properties of Carbon Nanotubes and Graphene Naonosheets Enhanced Phenol-formaldehyde Resin

Xiang-Feng Wu, Yong-Ke Zhao, Yun Zhang, Yu Zhu Wu, Yi Jin Wang, Hui Li, Chen Xu Zhang and Xin-Yue Yang

Graphene naonosheets were prepared via one-pot hydrothermal process in a Teflon-lined autoclave. Moreover, the mechanical and thermal degradation behaviors of the phenol formaldehyde/carbon nanotubes and phenol formaldehyde/graphene naonosheets composites were discussed. Experimental results showed that the graphene naonosheets possessed better performances than that of carbon nanotubes. When the filler loading was 0.6wt%, tensile strength, Young’s modulus, compressive strength and modulus of the as-prepared composites reached their maximum values, which were increased by 77.0, 141.3, 109.1 and 114.8% for graphene naonosheets and 54.7, 85.9, 61.7 and 45.2% for carbon nanotubes than those of pure sample, respectively. In addition, both of these two carbon materials could increase the thermo-stability of the matrix. When their usage amount was 0.6wt%, the thermal degradation temperature (at 10% weight loss) was increased to 255.6°C for phenol formaldehyde/graphene naonosheets composites and 253.5°C for phenol formaldehyde/carbon nanotubes composites from 233.6°C for pure sample.
Pages(737)
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Hydration Kinetics of Some Durum and Bread Wheat Varieties Grown in South-Eastern Region of Turkey

Ali Yıldırım

Hydration kinetics of wheat varieties grown in South-Eastern Region of Turkey, covering a temperature range from 25 to 50 oC was examined. Peleg’s model together with Arrhenius relationship were successfully used to evaluate water uptake of some Durum (Local names; Zenit and BurgosBurgos) and Bread (Local names; Dariyel and Karatopak) wheat varieties during soaking at a temperature range of 25-50 oC. Model was found to be suitable for describing the soaking behaviour of wheat kernels with a coefficient of determination (R2) and Root mean square error (RMSE) greater than 0.9805, and less than 0.051, respectively. The Peleg rate and capacity constants, K1 and K2, were affected by temperature and wheat varieties. Activation energy values of Zenit, BurgosBurgos, Dariyel and Karatopak wheats were found as 39.94, 38.03, 36.25 and 29.54 kJ mol-1, respectively. Zenit wheat was the least hydrated while Karatopak was the most hydrated one due to kernel size and protein content. General equations to describe the water uptake of wheat varieties as a function of soaking time, temperature and initial moisture content were developed. These derived equations can be used for wheat operations such as tempering, mixing, knedding etc.
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QSPR Models of Physicochemical Properties of Natural Amino Acids by Using Topological Indices and MLR Method

Afsaneh Safari and Fatemah. Shafiei

The mathematical has provided very useful tools for relationships between the structures and molecular properties. Topological indices are numerical parameters of a graph which characterize its topology and are usually graph invariant. In this study the relationship between the Randic' (1X), Balaban (J), Szeged (Sz), Harary (H), Wiener (W), Hyper-Wiener (WW) and Wiener Polarity (Wp)to the thermal energy (Eth kJ/mol), heat capacity (CV J/mol K) and entropy (SJ/mol K) of 19 natural amino acids is represented. Physicochemical properties are taken from the quantum mechanics methodology with HF level using the ab initio 6-31G basis sets. The multiple linear regressions (MLR) and Back ward methods (with significant at the 0.05 level) were employed to give the QSPR models. After MLR analysis, we studied the validation of linearity between the molecular descriptors in the best models for used properties. The predictive powers of the models were discussed by using the method of cross-validation. The results have shown that one descriptor (W) could be efficiently used for estimating the entropy (S), heat capacity (Cv) and Wiener Polarity index could be used for modeling and predicting the thermal energy of respect compounds.
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Photocatalytic Inactivation of Hospital-Associated Bacteria using Titania Nanoparticle Coated Textiles

Tehseen Tahir, Ishtiaq Ahmed Qazi, Imran Hashmi and Muhammad Anwar Baig

Modification in hospital textiles to include disinfection properties may help in the reduction of nosocomial infections. In this study, antibacterial properties were imparted to cotton fabric by modifying it with pure and (1%) silver doped titania nanoparticles. The nanoparticles were prepared by liquid impregnation process and characterized using X-ray Diffraction (XRD) spectroscopy, Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). These nanoparticles were attached to cotton fabric using a cross linking agent succinic acid. Samples were washed at three different temperatures (30, 60 and 90°C), with and without detergent and for different number of cycles to test the durability of nanoparticles to the fabric. Scanning Electron Microscopy (SEM) was used for studying surface topography of fabric. Energy Dispersive X-ray fluorescence (ED-XRF) spectrometer was used to detect the titanium present on the fabric. Catalytic spectrophotometry using UV/visible spectrophotometer was used to determine titania concentration in washing effluent. The antibacterial activity of the modified fabric was examined against Methicillin Resistant Staphylococcus aureus (MRSA) under UV and fluorescent light. The maximum durability of titania nanoparticles to the fabric was retained after washing without detergent at 30°C. The overall results of durability testing showed that coating of nanoparticles on fabric was durable against washing at various conditions, hence suitable from an environmental perspective. Antibacterial testing showed 100% photocatalytic inactivation of MRSA after 4 and 24 h of UV and fluorescent light exposure respectively. The potential of using such textiles in hospital environment was validated through the use of modified bed linen in a local hospital for a period of three days consecutively. The viable count indicated the reduced bacterial contamination on nano-coated fabric as compared to uncoated fabric. Bed linen, curtains, staff uniforms, lab coats and medical garments developed from titania nanoparticle coated fabric may improve hospital environment against antibiotic resistant bacteria.
Pages(758)
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Zinc Oxide Nanostructures of Controlled Morphology Prepared from Single Source Precursors by Wet Chemical Route

Hameed Ullah, Javid Khan, Habib Nasir, Asad Muhammad Khan, Mohsan Nawaz Masroor Ahmad Bangesh and Muhammad Irfan

Controlled and reproducible synthesis of ZnO nanoparticles with uniform size and shape is highly desirable for tuning its physico-chemical properties. Metal β-diketonates have many advantages as precursors in sol gel process over the conventional metal salts. Exploiting the advantageous characteristics of Zn(tmhd)2 (where tmhd = 2,2,6,6-tetramethylheptane-3,5-dionate), we have synthesized ZnO nanoparticles by wet chemical (sol gel) method in acidic (pH 3) and basic (pH 9) media, and subsequently annealed at 250°C and 550°C. The resulting particles exhibited Wurtzite (hexagonal) crystal structure. The variation in pH and temperature has shown appreciable impact on the crystallite size and the morphology of the final product. The increase in particle size with increasing sintering temperature was reflected in the band gap energy, IR spectra and surface area measurements. Cylindrical, rod like nanoparticles were obtained at acidic pH 3 while spherical particles were achieved at basic pH 9 when sintered at 250°C. However, the particles obtained at sintering temperature of 250°C and 550°C were morphologically different. The lower pH 3 particles have elongated and flat shapes, while the higher pH 9 have hexagonal rod like particles when sintered at 550°C.
Pages(771)
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Removal of Brilliant Green Dye from Aqueous Medium by Untreated Acid treated and Magnetite Impregnated Bentonite Adsorbents

Mohammad Ishaq, Siraj Sultan, Imtiaz Ahmad, and Khalid Saeed

The untreated bentonite (UB), acid treated bentonite (ATB) and magnetite impregnated bentonite (MIB) has been examined as adsorbents for the removal of Brilliant green (BG) dye from aqueous medium. The batch adsorption experiments were conducted at different pH, contact time, adsorbent dosage, dye concentration and temperature. The adsorption of BG was dependent on pH of the solutions and the optimized pH value for their adsorption is 8. The adsorption data were fitted to Freundlich and Langmuir adsorption models, which were best fitted to Langmuir isotherm model. The monolayer adsorption capacity of UB, ATB and MIB was 689.6, 785, 877 mg/g, respectively. The kinetic study was analyzed by pseudo first, second and intraparticle diffusion models. It was found that adsorption of BG onto all three adsorbents followed pseudo second order kinetic model. The prepared adsorbents were also characterized by scanning electron microscopy (SEM), energy dispersive X-rays (EDX) and XRD.
Pages(780)
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Cu-Based π-Complexation Adsorbent for Paraffin/Olefin Separation in Slurry Bed

Ruiyuan Tang, Yuanyu Tian, Shengjia Wang, Yingyun Qiao and Guiling Leng

The solid phase transition pressure swing sorption and the liquid phase complexing sorption integration technology is used to separate paraffin/olefin in the slurry bed reactor. The characterizations of the adsorbents are conducted by the N2 adsorption/desorption, FT-IR, XRD and TG techniques. The effects of different preparation method, a CuCl loaded coefficient and calcination temperature are studied. The results showed that specific surface area and total pore volume of the adsorbents are significantly decreased when compared to those of SiO2 and AC (active carbon). Furthermore, the adsorbents prepared by the impregnation method with SiO2 as carrier, CuCl loaded coefficient of 25.0 wt% and calcinated at 400 oC showed higher separation effects. The propylene/propane selectivity coefficient is reached 2.26, and this implied that the feasibility of adsorbents utilized in slurry bed for paraffin/olefin separation.
Pages(788)
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