磁性离子印迹聚合物的制备及其对水中Pb(Ⅱ)的吸附

以铅离子为模板离子、乙二醇二甲基丙烯酸酯和偶氮二异丁腈为交联剂和引发剂、稀盐酸为洗脱剂,采用微波辅助反相乳液悬浮聚合法,制备了磁性离子印迹聚合物(MIIP),通过SEM、FTIR、XRD和BET技术对其进行了表征,并将其用于水中Pb(Ⅱ)的吸附.在初始质量浓度60 mg/L、溶液pH 6、吸附温度303 K、吸附时间6...     

微波辅助光催化降解兽药环丙氨嗪

利用微波光催化实验装置研究了水溶液中兽药环丙氨嗪的光催化降解,探讨了添加微波无电极灯(EDL)对降解反应的促进作用.结果表明,环丙氨嗪在微波辅助1.0g/L TiO2光催化体系中反应20min降解率可达99.6%,检测到的主要降解产物为三聚氰胺.环丙氨嗪在pH3.0~9.0范围内的微波辅助光催化降解率都高于99%;增加TiO2用量和EDL数量均显著提高其降解率.外源添加NO3-离子明显降低了环丙氨嗪的降解率,主要由于NO3-对紫外光的强吸收和在TiO2表面带正电的空穴位的吸附作用.     

微波无极紫外方法对二沉池出水的消毒研究

采用自制微波无极紫外连续式消毒反应器,对二沉池出水进行消毒.紫外光源为自制圆柱形无极灯,灯内充汞10mg、氩气压强666.61Pa紫外光强5.07mW/cm²,进水流量0.072L/s,出水细菌总数2CFU/mL,大肠菌群数0.微波无极紫外作用过程中,微波破坏细胞壁细胞膜结构使蛋白质、K⁺等胞内物质产生渗漏,这种不可逆的破坏过程有效抑制紫外光复活现象.     

Comparison of sample digestion procedures for the determination of trace elements in antarctic krill by GF‐AAS

Two independent digestion procedures for Antarctic krill samples were compared. Dry ashing (DA) and microwave (MW) acid‐assisted digestion were tested for decomposing the samples to determine essential (Cu, Fe, Cr) and toxic elements (Cd, Pb) by graphite furnace‐atomic absorption spectrometry (GF‐AAS). A mixture of HNO₃ and H₂O₂ as digesting agent was used in the microwave procedure. For the dry ashing digestion, the organic matter was oxidated at 480°C in an open system. Both digestion methods were compared in terms of accuracy and applied to the analysis of a certified reference material: MURST‐ISS‐A2 (Antarctic krill).

The detection limits for the five elements analysed ranged from 3 to 150 ng g^‐1. Both digestion procedures are suitable for the decomposition of krill samples. However, dry ashing is not recommended to determine Pb and Cd because losses can occur.     

微波提取-离子色谱法测定气态污染物中的硫酸雾

建立了一种以微波提取气态污染物中的硫酸雾,用离子色谱仪进行分析的方法,微波提取效率高,提取时间短。用离子色谱仪来进行定量分析,回收率为96.6%～104%,相对标准偏差为2.5%～3.4%。     

Catalytic decomposition of low level ozone with gold nanoparticles supported on activated carbon

Highly dispersed gold nanoparticles were supported on coal-based activated carbon (AC) by a sol immobilization method and were used to investigate their catalytic activity for low-level ozone decomposition at ambient temperature. Nitrogen adsorption-desorption, scanning electron microscope (SEM), and X-ray photoelectron spectroscopy (XPS) were used to characterize the catalysts before and after ozone decomposition. The results showed that the supported gold nanoparticles prepared with microwave heating were much smaller and more uniformly dispersed on the activated carbon than those prepared with traditional conduction heating, exhibiting higher catalytic activity for ozone decomposition. The pH values of gold precursor solution significantly influenced the catalytic activity of supported gold for ozone decomposition, and the best pH value was 8. In the case of space velocity of 120000h⁻¹, inlet ozone concentration of 50mg/m³, and relative humidity of 45%, the Au/AC catalyst maintained the ozone removal ratio at 90.7% after 2500min. After being used for ozone decomposition, the surface carbon of the catalyst was partly oxidized and the oxygen content increased accordingly, while its specific surface area and pore volume only decreased a little. Ozone was mainly catalytically decomposed by the gold nanoparticles supported on the activated carbon.     

微波耦合类Fenton处理水中对硝基苯酚

针对对硝基苯酚环境危害大、难生物降解的特点,为克服传统Fenton适用pH范围窄的缺点,制备了CuO催化剂,并对微波耦合类Fenton氧化对硝基苯酚溶液进行了实验研究,考察了H2O2投加量、催化剂投加量、微波功率、辐照时间、溶液初始pH对PNP去除效果的影响.结果表明,在H2O2和催化剂投加量分别为0.06mol/L和0.3g/L,微波功率125W,不调节溶液初始pH(约为6)的条件下,初始浓度为50mg/L的PNP溶液反应6min去除率达92%, TOC去除63%.比较不同氧化体系,得到微波能够增大微波耦合类Fenton体系中?OH的生成量,从而提高对PNP的去除率.实验表明,CuO催化微波耦合类Fenton作为一种新型类Fenton反应,能克服传统Fenton适用pH范围窄的局限性,并且显著提高反应效率,拓展了Fenton反应在废水处理中的应用.     

褐煤脱水及水质净化研究

为实现褐煤提质并缓解褐煤产区缺水现状,采用微波及水热脱水方法对褐煤进行脱水改性并回收褐煤所脱水分.通过检测水分化学需氧量、氨氮、总磷、硬度、离子、有机化合物等各项指标,对褐煤中水分进行深入分析,并比较两种脱水方法的脱水、净化效果.结果表明微波方式脱水率可达70%~80%,除化学需氧量外,其它水质指标均符合工业用水标准,且杂质含量随微波功率增加而降低,利于净化回收.水热方式可有效改善褐煤煤质,脱水率最高可达87.44%,但各项水质指标均大大超出标准范围,且杂质含量在250℃工况下达到最大.两种冷凝水均检测到微量有毒金属元素、有毒致癌的多环芳烃及酚类化合物,将成为后续净化的主要脱除对象.     

几种新型水处理技术的研究应用进展

固定化微生物、湿式催化氧化(CWO)、微波和人工湿地是近年来倍受关注的废水处理新技术。着重介绍了固定化微生物技术的发展、制备方法及在多种废水中的研究应用情况;湿式催化氧化(CWO)是目前处理高浓度生化难降解工业有机废水的最佳方法之一;阐述了微波及人工湿地技术处理废水的基本原理、优越性和这方面的应用研究;并对这4种废水处理新技术做了总结和展望。     

微波消解技术在沉积物样品元素分析中的应用

在沉积物样品元素分析中样品预处理即样品的消解是一个重要步骤。微波样品消解技术近十几年来受到普遍关注。本文小结了这一技术在沉积物元素分析应用中的一些重要问题,包括消解试剂体系的选择,消解程序和时间的确定等。