Synthesis of polychlorinated dibenzofuran isomers and their gas chromatographic profiles

Fifty-one polychlorinated dibenzofuran (PCDF) isomers were synthesized by the structure specific methods starting from corresponding chlorophenol and chloronitrobenzene or chlorophenol and chlorodiphenyl iodonium salt. Structures of the synthesized PCDF isomers were confirmed by mass spectrometry and proton magnetic resonance spectroscopy. Gas chromatographic retention times and response factors of the PCDF isomers were determined on the fused silica capillary columns of SP-2330 and OV-101.     

Performance of photocatalytic reactors using immobilized TiO2 film for the degradation of phenol and methylene blue dye present in water stream

TiO2 thin film photocatalyst was successfully synthesized and immobilized on glass reactor tube using sol-gel method. The synthesized TiO2 coating was transparent, which enabled the penetration of ultra-violet (UV) light to the catalyst surface. Two photocatalytic reactors with different operating modes were tested: (a) tubular photocatalytic reactor with re-circulation mode and (b) batch photocatalytic reactor. A new proposed TiO2 synthesized film formulation of 1 titanium isopropoxide: 8 isopropanol: 3 acetyl acetone: 1.1 H2O: 0.05 acetic acid (in molar ratio) gave excellent photocatalytic activity for degradation of phenol and methylene blue dye present in the water. The half-life time, t1/2 of photocatalytic degradation of phenol was 56 min at the initial phenol concentration of 1000 microM in the batch reactor. In the tubular photocatalytic reactor, 5 re-circulation passes with residence time of 2.2 min (single pass) degraded 50% of 40-microM methylene blue dye. Initial phenol concentration, presence of hydrogen peroxide, presence of air bubbling and stirring speed as the process variables were studied in the batch reactor. Initial methylene blue concentration, pH value, light intensity and reaction temperature were studied as the process variables in the tubular reactor. The synthesized TiO2 thin film was characterized using SEM, XRD and EDX analysis. A comparative performance between the synthesized TiO2 thin film and commercial TiO2 particles (99% anatase) was evaluated under the same experimental conditions. The TiO2 film was equally active as the TiO2 powder catalyst.     

废水吸附法除磷的研究进展

本文叙述了利用吸附原理进行废水除磷的研究进展。吸附法除磷的研究主要表现在吸附材料的研究方面 ,基于应用场合的差异 ,包括廉价的天然材料、工业废渣及其改性物、传统的活性氧化铝及其改性物、其他多孔物质及人工合成的高效吸附剂等。人工合成高效吸附剂由于磷吸附容量大 ,其相关研究成为近年来的重要发展方向     

以磺酸阳离子交换树脂为原料合成含硫水不溶性杀菌剂

设计了一个新的以磺酸阳离子交换树脂为原料制备含硫水不溶性杀菌剂的合成路线，通过聚苯乙烯磺酸吡啶盐中间体合成磺酰氯树脂，在磺酰氯树脂上固载二乙胺，再用带有叔胺基的树脂与卤代烷作用合在含硫的铵盐型聚合物杀菌剂，使用所研制的水不溶性杀菌剂用量2mg/mL时杀菌率达到90％以上。     

带长链烷基季铵盐杀菌活性官能团树脂的合成

以强酸型阳离子交换树脂作载体 ,合成磺酰氯树脂后固载乙二胺并胺基叔胺化 ,最后加卤代烷合成带长链烷基季铵盐杀菌活性官能团树脂 ,确定了合成路线中的各步反应条件。对异养菌的杀菌性能测定结果表明 ,合成的杀菌树脂的杀菌率在测定条件下都达到了 90 %以上 ,有望用于工业和民用水的杀菌消毒     

Adsorption and redox reactions of heavy metals on synthesized Mn oxide minerals

Several Mn oxide minerals commonly occurring in soils were synthesized by modified or optimized methods. The morphologies, structures, compositions and surface properties of the synthesized Mn oxide minerals were characterized. Adsorption and redox reactions of heavy metals on these minerals in relation to the mineral structures and surface properties were also investigated. The synthesized birnessite, todorokite, cryptomelane, and hausmannite were single-phased minerals and had the typical morphologies from analyses of XRD and TEM/ED. The PZCs of the synthesized birnessite, todorokite and cryptomelane were 1.75, 3.50 and 2.10, respectively. The magnitude order of their surface variable negative charge was: birnessite> or =cryptomelane>todorokite. The hausmannite had a much higher PZC than others with the least surface variable negative charge. Birnessite exhibited the largest adsorption capacity on heavy metals Pb(2+), Cu(2+), Co(2+), Cd(2+) and Zn(2+), while hausmannite the smallest one. Birnessite, cryptomelane and todorokite showed the greatest adsorption capacity on Pb(2+) among the tested heavy metals. Hydration tendency (pK(1)) of the heavy metals and the surface variable charge of the Mn minerals had significant impacts on the adsorption. The ability in Cr(III) oxidation and concomitant release of Mn(2+) varied greatly depending on the structure, composition, surface properties and crystallinity of the minerals. The maximum amounts of Cr(III) oxidized by the Mn oxide minerals in order were (mmol/kg): birnessite (1330.0)>cryptomelane (422.6)>todorokite (59.7)>hausmannite (36.6).     

Facile in situ synthesis of silver nanocomposites based on cellulosic paper for photocatalytic applications

Environmental Science and Pollution Research - In this work, various photocatalysts were synthesized with an impregnation-precipitation process to in situ decorate Ag-based nanoparticles (NPs,...     

Synthesis, characterization and chromatographic separation of tetrachlorobenzene-related compounds

Sulphoxide, sulphone and mercapturic acid derivatives of isomeric tetrachlorobenzene were synthesized. These compounds and isomers of tetrachlorophenol were characterized by spectroscopic and chromatographic methods.     

Fluorescently visualizing the penetration of anionic surfactants across cytoplasmic membrane and the subsequent damage on human cells

Environmental Science and Pollution Research - The extensive application of chemically synthesized anionic surfactants would cause serious pollution of water and increase health risk to humans....     

Degradation of doxycycline antibiotics using lanthanum copper oxide microspheres under simulated sunlight

Environmental Science and Pollution Research - In this study, lanthanum copper oxide was synthesized under hydrothermal techniques and characterized for doxycycline degradation. The catalyst...     

Heterogeneous Fenton degradation of ofloxacin catalyzed by magnetic nanostructured MnFe2O4 with different morphologies

Environmental Science and Pollution Research - Magnetic nanostructured MnFe2O4 with different morphologies, synthesized via chemical co-precipitation and hydrothermal method, was assayed as...     

Synthesis and preparation of acid capped CdSe nanocrystals as successful adsorbent and photocatalyst for the removal of dyes from water and its statistical physics analysis

Environmental Science and Pollution Research - In this study, mercaptosuccinic acid capped CdSe nanocrystals were successfully synthesized and used as photocatalyst for the effective removal of...     

Photocatalytic degradation of atrazine in aqueous solution using La-doped ZnO/PAN nanofibers

Environmental Science and Pollution Research - Polyacrylonitrile (PAN)-based-modified zinc oxide (ZnO) nanofibers were synthesized by using electrospinning and hydrothermal techniques. The...     

Adsorptive and photocatalytic activity of Fe3O4-functionalized multilayer graphene oxide in the treatment of industrial textile wastewater

Environmental Science and Pollution Research - Multilayer graphene oxide (mGO) was synthesized and functionalized via co-precipitation method to produce magnetic Fe3O4-functionalized multilayer...     

Mesoporous carbon nanospheres derived from agro-waste as novel antimicrobial agents against gram-negative bacteria

Environmental Science and Pollution Research - Porous carbon nanospheres were synthesized from agro-waste garlic peels by a one-pot facile and easy to scale-up pyrolysis method. Surface morphology...     

Preparation of montmorillonite grafted polyacrylic acid composite and study on its adsorption properties of lanthanum ions from aqueous solution

Environmental Science and Pollution Research - Montmorillonite grafted polyacrylic acid composite (GNM) was prepared by using ultraviolet radiation grafting method in this work. The synthesized...     

An investigation on the promoting effect of Pr modification on SO2 resistance over MnOx catalysts for selective reduction of NO with NH3

Environmental Science and Pollution Research - Pr-modified MnOx catalyst was synthesized through a facile co-precipitation process, and the results showed that MnPrOx catalyst exhibited much better...     

Synthesis of magnetic nanoparticles and their effects on growth and physiological parameters of Calotropis procera seedlings

Environmental Science and Pollution Research - The present study was carried out to elucidate effects of synthesized magnetic nanoparticles (MNPs) on morphological and physiological parameters and...     

Evaluation of hydroxyapatite/poly(acrylamide-acrylic acid) for sorptive removal of strontium ions from aqueous solution

Environmental Science and Pollution Research - A composite polymer, hydroxyapatite/poly(acrylamide-acrylic acid), was synthesized by gamma-induced polymerization. The factors affecting the sorption...     

Purifying arsenic and fluoride-contaminated water by a novel graphene-based nanocomposite membrane of enhanced selectivity and sustained flux

Environmental Science and Pollution Research - A novel graphene-based nanocomposite membrane was synthesized by interfacial polymerization (IP) through chemical bonding of the graphene oxide (GO)...