Jian Zhang

Present status on removal of raff inose family oligosaccharides – a Review | Jian Zhang, Guangsen Song, Yunjun Mei, Rui Li, Haiyan Zhang, Ye Liu | Agricultural Journals

The complexes of gossypol with Fe ²⁺ were prepared by using methanol as solvent in the presence of CO ₂ atmosphere. The results from FT‐IR spectra analysis indicated that the aromatic aldehyde groups in gossypol molecules were entirely involved in coordination with Fe ²⁺ . UV‐Vis absorption spectrum of the complexes in methanol solution displays blue‐shift in comparison with that of gossypol. Five compounds from the complexes were isolated by high performance liquid chromatography. The structures of the complexes are consistent with PM3 calculations. Two compounds were formed by coordination of gossypol with Fe ²⁺ at 1:2 molar ratio, other three compounds were formed by chelation of gossypol with Fe ²⁺ at molar ratio by 1:1, 1:3, and 1:4 respectively.

BACKGROUND: In China, soil pollution is becoming more and more serious with the national economy rapidly developing. How to remedy soil containing heavy metals in an effective and low cost way is increasingly becoming an urgent problem. Utilization of renewable photovoltaic energy in the environmental protection field brings forward a solution.RESULTS: Cr(VI) removal from soil using an electrokinetic remediation process powered by photovoltaic solar modules and a DC–DC converter was studied. The results show that under solar irradiation intensity of 650 ± 20 W m⁻² and 9 V output voltage of the converter, Cr(VI) removal efficiency of an iron electrode can increase to 99.8% in 30 min. For output voltage in the range 3–11.5 V, voltage has a significant effect on Cr(VI) removal efficiency. When initial Cr(VI) concentration is increased from 200 mg kg⁻¹ to 450 mg kg⁻¹, Cr(VI) removal efficiency and removal rate decrease. Total Cr concentrations and XRD analysis show that chromium in soil is accumulated near the anodic zone after electrokinetic remediation. For the highest voltage of 11.5 V, although sunlight utilization efficiency is the highest, electric energy consumption is the largest, and EPV and EPM are 249.4 kWh kg⁻¹ and 156.1 kWh m⁻³, respectively.CONCLUSION: The process used for removal of Cr(VI) from soil is feasible. © 2014 Society of Chemical Industry

The determination of chloride in copper sulfate pentahydrate recycled from printed circuit board was carried out by precipitation of SO 4 2- with barium nitrate, followed by leaching and lavation, and chloride in the filtrate could be quantitatively detected by potentiometric titration method using a standard solution of silver nitrate. End volume was estimated by plotting of d 2 E/dV 2 versus addition volumes of silver nitrate. It was easily read by Excel software that the stoichiometric point was at the intersection between the curve and X-axis. The results suggested that tested results by the standard addition method gave a value of relative deviation of ≤ 4.0% (n=5) while the values of relative standard deviation (s/n=5) for three unknown samples were lower than 3.0%. Therefore, the method was proposed for the determination of chloride in copper sulfate pentahydrate recycled from printed circuit board.

The proper extraction conditions for phenol, o-chlorophenol and o-nitrophenol were investigated by using the liquid-solid extraction system composed of Tween 80-sodium citrate-H ₂ O. 10.5% (v/v) Tween 80, 2.6000 g·l ^-1 sodium citrate, extraction acidity of pH 5.95 had been found optimal for extraction of phenolic compounds. Under the above-mentioned conditions the once average recoveries of phenol, o-chlorophenol and o-nitrophenol in analogous water samples were 99.5%, 95.3%, 94.7%, respectively. When sodium citrate was as salt separate phase, the acidity of the solution not only could change the shape of sodium citrate, but also had effects on extraction yield (E%) of phenols as well. Through the discussion of the extraction mechanism for Tween 80 solid phase, it was indicated that the extraction in this system had been achieved by the formation of the hydrogen bond between Tween 80 and the phenolic compounds.