Optimizing Removal of COD from Water by Catalytic Ozonation of Cephalexin Using Response Surface Methodology

Response surface methodology (RSM) has been used to optimize the effect of circulation rates, ozone supply, cephalexin (CEX) concentration, and granular activated carbon (GAC) dose on removal of COD from solution. According to statistical analysis, all of the input variables exerted significant influence on COD removal, however, the effect of interaction variables was not found to be significant on comparative basis. Further, the developed quadratic regression model based on obtained results emphasized the significance of individual terms and little of interaction terms. The values of r2 (0.959), adjusted r2 (0.902) obtained by analysis of variance (ANOVA) indicates the significance of quadratic model in predicting desired response. The maximum of 70% of COD was removed in these experiments and optimized value according to main effect of variables was 60%.read more

Javaid Akhtar, Noraishah Saidina Amin and Muhammad Khurram Zahoor

Combined Influence of Extraction Parameters on Degree of Esterification of Sugar Beet Pulp Pectin: A Preliminary Study

A Box-Behnken design was employed to study the combined effects of variables of microwave-assisted extraction on pectin from sugar beet pulp. The independent variables were time and power of microwave-assisted extraction, pH of sulfuric acid and rate of solid to liquid (SLR). The combined effects of these variables on degree of esterification (DE) were studied. Results have shown that the generated regression model significantly explained the actual relationship between the independent variables and response. Besides that, pH was the most important variable which affected the DE. Higher acid concentration, extraction power and longer extraction time increased the DE of pectin due to Esterification. Through the response surface, the satisfactory conditions for extraction of high-ester sugar beet pulp pectin were obtained as follows: 1.02 of pH, 3.96 min of extraction time, 193.68W of power and 19.98 of SLR.read more

Deqiang Li, Jianjiang Shang, Xinfang Ma, Xiaoyan Zhu and Zhiyong Liu

Simultaneous Separation and Purification of Tea Bioactives from summer Green Tea by Column Chromatography

In the present study, feasibility of producing high quality of tea polyphenols, theanine and caffeine from the extract of summer green tea by column chromatography was investigated. Crude extract of summer green tea obtained by hot water extraction was passed through columns of polyamide and NKA-II macroporous resin respectively, resulting in tea polyphenols-enriched fraction (96.27 ± 1.78%), theanine-enriched fraction (99.02 ± 0.43%) and caffeine-enriched fraction (99.25 ± 0.36%). The recovery rates for tea polyphenols, theanine and caffeine were 72.42 ± 1.41%, 66.12 ± 1.66% and 62.07 ± 2.17%, respectively. The separation procedure allowed the production of such products by decreasing impurities and avoiding the use of poisonous organic solvent. The results suggested that it was possible to produce high-quality products of rich-in tea polyphenols, theanine and caffeine by a simple way. From industrial point of view, this novel method has many merits such as high efficiency of separation, low consumption of energy and environment-friendly procedure.read more

Xin Zhang, Shi Cheng Lei, Saqib Jabbar, Bing Hu, Yi Sun and Xiao Xiong Zeng

Determination of Synthetic Phenolic Antioxidants in Cake by HPLC/DAD after Mixed Micelle–Mediated Cloud Point Extraction

A mixed micelle-mediated cloud point extraction (MMCPE) system was developed for the extraction and preconcentration of four synthetic phenolic antioxidants (SPAs) (propyl gallate (PG), tert-butylhydroquinone (TBHQ), butylated hydroxyanisole (BHA) and octyl gallate (OG) ) in cake. The mixture of two kinds of non-ionic surfactants polyoxy ethrlene nonyl phinyl ether (NP-7) and polyoxy ethrlene nonyl phinyl ether (NP-9) was utilized as a suitable micellar medium for preconcentration and extraction of SPAs. The surfactant-rich phase was then analyzed by high performance liquid chromatography-diode array detection (HPLC–DAD). The effect of different parameters such as concentration of surfactants, proportion of NP-7 and NP-9, equilibration time and temperature on the cloud point extraction (CPE) was carefully optimized. Under the studied conditions, four SPAs were successfully separated within 12 min. The relative standard deviations (RSD, n=6) were 1.2–2.0% and the limits of detection (LOD) were 1.5 ng mL-1 for PG, 3.6 ng mL-1 for TBHQ, 2.9 ng mL-1 for BHA, and 0.8 ng mL-1 for OG, respectively. Recoveries of the SPAs in spiked cake samples were in the range of 92% to 99%. The MMCPE method showed potential advantage for the preconcentration of the SPAs, with enrichment factor of 25. Moreover, the method is simple, has high sensitivity, consumes much less solvent, and has significant advantage in extraction efficiency compared to traditional CPE methods.read more

Peijin Wang, Dongling Meng, Chang liu and Yaling Yang

Physichemical Properties of Different Corn Varieties by Principal Components Analysis and Cluster Analysis

Principal components analysis and cluster analysis were used to investigate the properties of different corn varieties. The chemical compositions and some properties of corn flour which processed by drying milling were determined. The results showed that the chemical compositions and physicochemical properties were significantly different among twenty six corn varieties. The quality of corn flour was concerned with five principal components from principal component analysis and the contribution rate of starch pasting properties was important, which could account for 48.90%. Twenty six corn varieties could be classified into four groups by cluster analysis. The consistency between principal components analysis and cluster analysis indicated that multivariate analyses were feasible in the study of corn variety properties.read more

Jie Zeng , Haiyan Gao, Guanglei Li and Junliang Sun

Study of Composite Carrier Based on Organic and Inorganic Polymers

In this work, the possibility of obtaining composites on the basis of polyvinyl alcohol and bentonite clay Manrak deposit has been investigated. The interaction of polyvinyl alcohol with bentonite clay was studied by employing methods such as equilibrium swelling, sedimentation, electrophoresis, viscometer, and scanning electron microscopy. It was established that the interaction of polyvinyl alcohol and bentonite clay are due to the hydrogen bonding between them. The composite gels with the improved structural-mechanical and prolonged effect have been formed on a base both of polyvinyl alcohol and clay.read more

Bates Malikovna Kudaibergenova, Marat Kianovich Beisebekov, Shynar Nurlanovna Zhumagalieva, Madiar Maratovich Beisebekov, Zharylkasyn Abduachitovich Abilov and Muhammad Iqbal Chaudhary

Preparation of Amine Functionalized Porous Silica by Ultrasonic Technique for the Methylation Reaction of Phenol with Dimethyl Carbonate

Amine functionalized silica catalysts, including (3-aminopropyltrimethoxysilane (APTMS)) NH2/SiO2, (Diazabicycloundecene/SiO2) DBU/SiO2 and (1, 5, 7-triazabicyclo [4, 4, 0] dec-5-ene/SiO2) TBD/SiO2, which were characterized by 29Si NMR, elemental analysis and indicator dye adsorption, were prepared by ultrasonic technique under mild conditions. Such hybrid solid bases showed high catalytic activity and well reusability towards the methylation reaction of phenol with dimethyl carbonate (DMC).read more

Xuehong Zhang, Shubin Liu, Yanlei Gao, Yunxiao Zhang, Lei Ren Ruisheng Hu and Rufen Chen

Simultaneous Determination of Five Flavonoids in Saussurea involucrata by Capillary Electrophoresis

A method of determination of five flavonoids in Saussurea involucrata by β-cyclodextrin modified capillary zone electrophoresis has been developed.The effects of buffer pH and buffer concentration, applied voltage and β-CD concentrations on the separation were systematically investigated. The optimum condition providing baseline separation of all compounds within 8 min was obtained in the 20 mmoll-1 borax buffer (pH 9.2), 20 kV applied voltage and 8 mmoll-1 β-CD. The linearity, detection limits, limits of quantification, reproducibility and recovery were satisfactory. The β-cyclodextrin modified capillary zone electrophoresis method proposed here has been satisfactorily employed to analyze S. involucrate samples.read more

Yumei Li and Hao Zhong

Molten Salt Synthesis of Iron Oxide Modified Attapulgite for Catalytic Oxidation of Elemental Mercury

Iron oxide modified attapulgite (Fe2O3-ATP) catalysts, with special network structure, were prepared by molten salt method, and were applied to investigate Hg0 oxidation ability in simulated flue gas from 100 to 260°C. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) spectroscopy were employed to characterize the catalysts. The results showed that Fe2O3-ATP exhibited about 90% average Hg0 oxidation efficiency at 220°C. With the decrease of the Fe2O3 in Fe2O3-ATP, the Hg0 oxidation efficiency reduced. Furthermore, the flue gas components seriously affected the Hg0 oxidation. The presence of Cl2 and O2 could promote the Hg0 oxidation, while SO2 would inhibit Hg0 oxidation. Cl2 was the most effective component of the three for Hg0 oxidation.read more

Yu Lu, Jing Ling Shao, Hui Cang, Fen Nv Han, Zhi Dong Chen and Qi Xu

Analysis of Samarium and Europium in Wheat by ICP-MS after On-Line Separation and Preconcentration

Europium and Samarium in wheat were determined by inductively coupled plasma mass spectrometry (ICP-MS) after flow injection on-line separation and preconcentration with P507 resin micro-column. The enhancement factors of 20 and 17 were achieved for samarium and europium, respectively. The instrumental detection limits were 0.00016 ng/ml and 0.000058 ng/ml for samarium and europium, respectively. The sample throughput was 13 s/h. The developed method was applied to analyze GBW 07605 certified tea reference material and the results were in good agreement with the certified values. The method was also assessed for determination of samarium and europium in wheat samples and the distribution of europium and samarium in different parts of wheat were discussed.read more

Yong Zhang, Zhihua Ning, Luzhi Sui and Hao Zhong