PSAA水溶液中铝形态分布研究

PSAA是一种含有铝离子的聚硅酸絮凝剂。本文用²⁷Al－NMR法和Al－Ferron逐时络合比色法研究了PSAA水溶液中铝的形态分布情况,考察了SiO₂/Al³⁺摩尔比,温度及稀释作用对铝的形态分布的影响。结果表明,PSAA水溶液中的铝主要是以单核羟铝络合物形式存在,聚硅酸的存在对铝的形态分布影响不大,温度对铝的形态分布无影响,稀释作用对铝的形态分布有一定的影响。     

水中六六六与五氯苯酚的光催化氧化

以高压汞灯不光泊,ＴｉＯ２为催化剂,研究了水中低浓度六六六五与五氯苯酚的光催化氧化。六六六易被光催化氧化,其４种异构体的半衰期十分接近,均在２０ｍｉｎ左右。ＰＨ中性条件下γ六六六的氧化速率较高。六六六光催化氧化存在含氯中物,并可逐渐被氧化去除。五氯苯酚光催化氧化速率明显高于光分解。３０ｍｉｎ之内五氯苯酚即可完全脱氯。随反应过程的继续,五氯苯酚被氧化成简单的小分子直至完全矿化。该法在饮用水深度处理中     

从废蚀刻液中回收资源的应用研究

从电路板蚀刻液回收硫酸铜及制作再生蚀刻液进行了工艺探索 ,得出中和法可从蚀刻液中脱除约 90 %的铜 ,沉淀氢氧化铜的最佳pH值为 5 6～ 6 0。采用水合肼还原法与硫化钠沉淀法可进一步脱除蚀刻液中的铜。研究结果表明 ,水合肼还原法回收海绵铜 ,在pH值为 6 0 ,反应温度 4 0℃ ,水合肼的投加浓度为 3%时 ,铜的回收率达到了 98%以上。而硫化钠沉淀法可取得 99%以上脱除废液中的铜效果 ,且具有适应范围广 ,操作成本低的优势。进一步除铜后的废液可回用于制新蚀刻液     

外加气体对等离子体降解水相中有机污染物的影响研究

研究了等离子体在内电极通氧气、氮气、空气和氦气条件下降解甲基紫的机理。研究表明,在该等离子体发生器结构下,等离子体能降解甲基紫,且在不同气体气氛下的降解产物不同,在氧气氛围下为含—CO和—OH物质及直链烯烃,而氮气氛围下是含—N、—NH和—OH的芳香类物质及小分子烃类物质。研究同时表明,等离子体降解水相中有机物时应在氧气介质中进行,如用空气则有可能会造成水体中NO-3过高。     

SPE-HPLC法测定固体废物浸出液中苯酚类物质

选择Agilent Bond Elut Plexa作为固相萃取柱,结合高效液相色谱测定固体废物浸出液中12种苯酚类化合物,通过试验优化条件,使目标物在0.100 mg/L~10.0 mg/L范围内线性良好,方法检出限在0.004μg/L~0.068μg/L之间,3个质量浓度水平加标回收率为78.0%~105%,测定6次结果的RSD为0.7%~5.0%。将该方法用于测定江苏省某工业园区污水处理企业5个废水处理污泥样品,结果 2,4,6-三氯苯酚和2,4-二硝基苯酚检出。     

Polyaniline nanofibers: acute toxicity and teratogenic effect on Rhinella arenarum embryos

The fate and effect of nanomaterials in the environment is of paramount importance towards the technological application of the materials. This work shows the ecotoxicological potential of polyaniline (PANI) nanofibers in the larvae Rhinella arenarum by means of AMPHITOX test. Acute toxicity of PANI nanofibers towards embryos of the common South American toad R. arenarum (Anura: bufonidae) was evaluated in the premetamorphosis (stage 25) larvae. The exposure of R. arenarum larvae to at dose of 150, 250 and 400 mg L⁻¹ resulted in 100% viability within 96 h exposure. The embryos at 2-4 blastomers stage (early life stage teratogenic test) revealed that embryos were not killed and no teratogenic effects were observed when embryos were incubated with PANI nanofibers (150 and 250 mg L⁻¹), while only a growth retardation of embryos was induced at levels of 250 mg PANI nanofibers L⁻¹. On the other hand, at 400 mg L⁻¹ concentration, a reduction in the body length of larvae and tail malformation was observed. This results suggest that a concentration-dependent toxicity is operative, typified by phenotypes that had abnormal body axes. The presence of PANI nanofibers in gut contents and its excretion by larval stages of R. arenarum was confirmed by UV-visible spectroscopy.     

New best estimates for radionuclide solid–liquid distribution coefficients in soils,Part 1: radiostrontium and radiocaesium

Best estimates for the solid-liquid distribution coefficients (K_d) of radiostrontium and radiocaesium for various soil types, were derived from geometric means (GM) calculated from grouping soils by texture and organic matter content, and also using soil cofactors governing soil–radionuclide interaction. The K_d (Sr) GM for Sand, Loam, Clay and Organic groups were similar, although the value for the Sand group was significantly lower. The Sr cofactor approach, based on the ratios of cation exchange capacity (CEC) to Ca and Mg concentrations in the soil solution, leads to K_d (Sr) GM with a lower variability, from which best estimates could be proposed. The K_d (Cs) GM for Sand and Organic groups differed, although similar values were obtained for Loam and Clay groups. Grouping the K_d (Cs) according to the Radiocaesium Interception Potential (RIP) and the RIP divided by the K concentration in the soil solution also allows to suggest K_d (Cs) best estimates with a lower variability.     

Dehydrochlorination behavior of polyvinyl chloride and utilization of carbon residue: effect of plasticizer and inorganic filler

The dehydrochlorination behavior of plasticizer (DOP) and inorganic filler (CaCO₃) contained in PVC samples and the properties of the activated carbons produced from those carbon residues have been investigated. In the dehydrochlorination process, both additives contributed not only to a decrease in HCl yield but also to the prolonged evolution of HCl. Part of the Cl species were observed to be stabilized as CaCl₂ by reaction with calcium ions when CaCO₃ was added. More than 80% of chlorine removal was achieved in all samples at 533 K. The use of potassium as an activation agent led to the production of activated carbon with a specific surface area greater than 1000 m²/g at the low temperature of 1023 K and assisted also in the elimination of residual Cl species by the formation of KCl during activation. Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6     

采用重选法处理蚀刻废液零排放资源化新工艺

阐述了广州市白云区南溪化工厂开发出的一套国内首创的对线路板蚀刻废液进行大规模集中资源化处理的零排放处理新工艺,这套新工艺采用重力分选的方法将在固相条件下生成的氧化铜分离出来,克服了原有工艺的缺陷,达到了理想的分离效果,使废液中所有的成分能够在较低的处理成本下全部分离回收,完全无三废排出,达到了清洁生产的要求。     

应用逼近于理想解的排序法优选环境监测点位的研究

尝试应用逼近于理想解的排序法进行环境监测点位的研究,证明此法具有简便、易行、实用性和科学性较强的特点.