氨荒酸膦酸树脂滤器的制备及其在AAS分析中的应用研究

介绍了氨荒酸膦酸树脂过滤器的制备方法,以及应用该过滤器分离与富集地面水(海水)中Cu、Pb、Zn、Cd等元素的适用条件。实际样品中的Cu、Pb、Zn、Cd等重金属离子经过过滤器过滤,被吸附在树脂滤层中,用少量酸洗脱,以AAS测试,结果稳定、准确度高。此过滤器在痕量分析中具有很高的应用价值。     

Chloramination of wastewater effluent: Toxicity and formation of disinfection byproducts

The reclamation and disinfection of waters impacted by human activities (e.g., wastewater effluent discharges) are of growing interest for various applications but has been associated with the formation of toxic nitrogenous disinfection byproducts (N-DBPs). Monochloramine used as an alternative disinfectant to chlorine can be an additional source of nitrogen in the formation of N-DBPs. Individual toxicity assays have been performed on many DBPs, but few studies have been conducted with complex mixtures such as wastewater effluents. In this work, we compared the cytotoxicity and genotoxicity of wastewater effluent organic matter (EfOM) before and after chloramination. The toxicity of chloraminated EfOM was significantly higher than the toxicity of raw EfOM, and the more hydrophobic fraction (HPO) isolated on XAD-8 resin was more toxic than the fraction isolated on XAD-4 resin. More DBPs were also isolated on the XAD-8 resin. N-DBPs (i.e., haloacetonitriles or haloacetamides) were responsible for the majority of the cytotoxicity estimated from DBP concentrations measured in the XAD-8 and XAD-4 fractions (99.4% and 78.5%, respectively). Measured DBPs accounted for minor proportions of total brominated and chlorinated products, which means that many unknown halogenated compounds were formed and can be responsible for a significant part of the toxicity. Other non-halogenated byproducts (e.g., nitrosamines) may contribute to the toxicity of chloraminated effluents as well.     

Occupational Exposure to Harmful Chemical Substances While Processing Phenol-Formaldehyde Resins

Air pollutants emitted while processing phenol-formaldehyde resins have been investigated. Gas chromatography-mass-selective detection was used to separate and identify chemical compounds. It was determined that workers were exposed to formaldehyde in all workplaces. Besides, phenol, acetaldehyde, acrylaldehyde, 2-furaldehyde, xylene, ethylbenzene, toluene, tetrachlorethene, ethyl acetate, butyl acetate were found during the production of frictional materials; and 2-furaldehyde, phenol, naphthalene, 2-furan-methanol, polycyclic aromatic hydrocarbons (PAHs) during the production of abrasive materials. Quantitative analyses were performed with gas chromatogra-phy and high performance liquid chromatography. Assessment of occupational exposure indicated that chemical compounds emitted during the investigated processes might be dangerous for human health, mainly because of suspected carcinogenic compounds: formaldehyde and PAHs.     

A new regeneration approach to cation resins with aluminum salts: application of desalination by its mixed bed

A novel method for the regeneration of cation exchange resins by aluminum (Al) salts was investigated in order to improve the regeneration efficiency of resins and reduce the dosage of regenerant. The influences of Al³⁺ concentration and the pH of regeneration solution on resin transformation had been studied. The desalination experiments were carried out to evaluate the characteristics of the Al form resins. Experimental results showed that the regeneration rate of resins was strictly dependent on Al3+ concentration and the pH of the solution. Compared to the conventional regeneration method, the Al form mixed bed exhibited the same desalination capability as the H form mixed bed (MB), and the total organic carbon (TOC) removal was up to 90%, clearly higher than that of the H form. Al salt solution could be utilized repeatedly to regenerate Al form resins.     

载钯树脂对偶氮类染料的吸附降解及其产物对发光菌的毒性暴露试验

合成了表面负载金属钯的聚丙烯醛异烟酰腙树脂后,通过Q67发光菌的毒性暴露实验研究了该树脂材料对直接大红、直接天蓝和桃红等3种水溶性偶氮染料的催化降解效果及其在降解过程中对发光菌的生物毒性变化情况,并对降解结果进行了气相色谱-质谱(GC-MS)分析.实验结果表明:载钯树脂对直接大红、直接天蓝和桃红等偶氮染料具有良好的吸附...     

Sorption of the herbicides diquat and difenzoquat from aqueous medium by polymeric resins in the presence of sodium dodecylsulfate: Kinetic and mechanistic study

The goal of this work was to propose a novel method for the solid-phase extraction of the herbicides diquat (DQT²⁺) and difenzoquat (DFQT⁺) from aqueous medium using polymeric Amberlite XAD-2 and XAD-4 resins in the presence of sodium dodecylsulfate (SDS). The addition of SDS to the medium was of fundamental importance in order to allow the formation of a negatively charged surface able to sorb the cationic solutes. Several factors that could influence the sorption process, such as SDS concentration in the medium, sorbent mass, pH, ionic strength, and initial concentration of the solutes were investigated. Kinetic studies were also performed to model the system and to identify the mechanisms that operate the sorption process of the herbicides. SDS concentration in the medium presented remarkable influence on the extraction efficiency, achieving maximum values when the ratios [SDS]/[herbicide] were approximately 90, for XAD-2, and 22 and 11 for DQT²⁺ and DFQT⁺, respectively, for XAD-4. The sorption process followed a pseudo second-order kinetic in all cases studied. It was also found that an intraparticle diffusion process controlled exclusively the sorption of the herbicides by the Amberlite XAD-2 and XAD-4 resins in the first 15 min, becoming less active with time.     

离子交换树脂处理钢铁钝化含铬废水的研究

针对钢铁钝化含铬废水污染,采用弱碱阴离子交换树脂进行了系统的研究,通过静态试验考查了pH值、振荡时间和离子交换树脂用量的影响,使用反应柱动态试验法研究了树脂的再生,得到了令人满意的结果。     

新型固化单宁大孔吸附树脂的合成

应用曼尼希反应将植物单宁固定在苯乙烯-二乙烯苯共聚物上,制备一种新型固化单宁大孔吸附树脂.系统研究了胺基树脂的合成及其与单宁固化的工艺合成试验,得出最佳工艺条件为:胺基树脂:甲醛:单宁(质量比)=2:0.74:1,反应温度99～100℃,反应时间7 h.制备的固化单宁大孔吸附树脂具有较好亲水性,对水溶液中苯酚的吸附容量可达90 mg/g.该树脂易洗脱再生,重复使用效果好,对实际含酚废水的富集回收均获得了令人满意的结果.     

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。     

Recent Industrial Applications of Lignin: A Sustainable Alternative to Nonrenewable Materials

Lignin represents a vastly under-utilized natural polymer co-generated during papermaking and biomass fractionation. Different types of lignin exist, and these differ with regard to isolation protocol and plant resource (i.e., wood type or agricultural harvesting residue). The incorporation of lignin into polymeric systems has been demonstrated, and this depends on solubility and reactivity characteristics. Several industrial utilization examples are presented for sulfur-free, water-insoluble lignins. These include materials for automotive brakes, wood panel products, biodispersants, polyurethane foams, and epoxy resins for printed circuit boards.