管道内烟气喷雾脱硫的研究

对不同SO2 初始浓度下 ,竖直管道内利用石灰浆喷雾脱除烟气中二氧化硫的方案做了实验研究 ,以模拟石灰液喷雾对燃煤锅炉尾气中SO2 的吸收效果。结果表明 ,可以在较低的钙硫摩尔比下 ,用这一方法使中等浓度SO2 烟气获得较高的脱硫效率。本研究结合双膜理论和双反应面模型 ,对石灰浆滴吸收SO2 的机理给出了解释 ,说明了实验现象和某些类似实验研究的结果。     

一个液相化学反应机理的建立和应用

利用比较积分反应速率的方法，建立了一个简化液相化学反应机理ＡＲＣＭＬ，并在各种大气状况下以及各种物理参数下对ＡＲＣＭＬ作了验证，然后利用ＡＲＣＭＬ模拟光化学烟雾形成初期的云水酸化过程，结果表明，自由基氧化Ｓ（Ⅳ）在污染或高ＮＯｘ的大气中非常重要。     

非均相催化电解法处理焦化废水

采用三维电极固定床技术对焦化废水进行了深度处理的实验研究,并取得了相应的工艺参数.实验研究结果表明,三维电极技术能有效的处理焦化废水,在槽电压为12V,液体催化剂量为1500mg/l,反应时间为60min,ph为3,CODcr去除率可达62%.     

Radiation-induced reduction of chromium(VI) in aqueous solution by γ-irradiation in a laboratory-scale

Introduction Chrom ium com pounds are extensively used in electroplating, leather-tanning and other industries. In C hina, chrom ium is incorporated into the environ- m ent, m ainly into soils and stream s of w ater, as a result of unregulated application…     

DNA氧化损伤在太阳光致M13mp2噬菌体突变中的作用

以野生型大肠菌ＣＳＨ５０及ｍｕｔＭ缺陷的大肠菌ＭＦ６７为宿主，观察了太阳光对Ｍ１３ｍｐ~２噬菌体单链ＤＮＡ ｌａｃＺα基因区域的致突变性．结果显示，太阳光照射引起噬菌体ｌａｃＺα基因区域的突变，在ｍｕｔＭ缺陷的宿主中更为明显；０．２５ｍｏｌ／Ｌ的甘露醇可以部分拮抗太阳光的致突变作用．以ＥＳＲ自旋捕捉法检测了太阳光、长波紫外线（ＵＶＡ）及中波紫外线（ＵＶＢ）照射Ｍ１３ｍｐ~２噬菌体样品中的自由基，结果还显示，太阳光和ＵＶＡ照射可引起羟自由基的产生，而ＵＴＢ照射则没有明显的自由基信号产生说明太阳光致突变作用与ＤＮＡ氧化损伤有关，羟自由基在其中发挥一定的作用     

改进彩管行业含铬废水处理工艺

针对彩管行业含铬废水处理工艺存在的不足,分别从还原剂和混凝剂两方面进行改进.通过比较和分析,最终提出了采用FeSO4作为还原剂处理含铬废水,氧化还原反应pH调节范围扩大,运行安全系数提高;利用新型高效混凝剂配合泥回流工艺,化学药品用量大幅下降,出水COD和SS含量显著减少.     

污染物与蒙脱石层间域的界面反应及其环境意义

系统地评述了无机、有机阳离子、农药分子、细菌等环境污染物在蒙脱石层间域中的吸附、脱附、氧化还原、催化降解等界面反应机理 ,并指出它们的环境化学行为对环境的影响和意义     

Synthesis of branched para-nonylphenol isomers: occurrence and quantification in two commercial mixtures

Eight tertiary nonanols were synthesized via Grignard reaction and coupled by Friedel–Crafts alkylation with phenol to the corresponding nonylphenols. Six branched para-nonylphenols (NP) were obtained: 4-(3′-methyl-3′-octyl)phenol (33NP), 4-(2′-methyl-2′-octyl)phenol (22NP), 4-(2′,5′-dimethyl-2′-heptyl)phenol (252NP), 4-(2′,5′,5′-trimethyl-2′-hexyl)phenol (2552NP), 4-(2′,4′-dimethyl-2′-heptyl)phenol (242NP) and 4-(4′-ethyl-2′-methyl-2′-hexyl)phenol (4E22NP). Their structures were confirmed by GC–MS and NMR spectroscopy. These six isomers as well as the earlier synthesized 4-(3′,5′-dimethyl-3′-heptyl)phenol (353NP), 4-(3′,6′-dimethyl-3′-heptyl)phenol (363NP) and 4-(2′,6′-dimethyl-2′-heptyl)phenol (262NP) were compared with commercial NP mixtures purchased from Acros and Fluka by GC–MS (equipped with a 100 m polysiloxane column). The analyses revealed that all obtained isomers are occurring in different quantities in both commercial NP mixtures.     

Photochemical degradation and mineralization of 4-chlorophenol

INTENTION, GOAL, SCOPE, BACKGROUND: Since the intermediate products of some compounds can be more toxic and/or refractory than the original compund itself, the development of innovative oxidation technologies which are capable of transforming such compounds into harmless end products, is gaining more importance every day. Advanced oxidation processes are one of these technologies. However, it is necessary to optimize the reaction conditions for these technologies in order to be cost-effective. OBJECTIVE: The main objectives of this study were to see if complete mineralization of 4-chlorophenol with AOPs was possible using low pressure mercury vapour lamps, to make a comparison of different AOPs, to observe the effect of the existence of other ions on degradation efficiency and to optimize reaction conditions. METHODS: In this study, photochemical advanced oxidation processes (AOPs) utilizing the combinations of UV, UV/H2O2 and UV/H2O2/Fe2+ (photo-Fenton process) were investigated in labscale experiments for the degradation and mineralization of 4-chlorophenol. Evaluations were based on the reduction of 4-chlorophenol and total organic carbon. The major parameters investigated were the initial 4-chlorophenol concentration, pH, hydrogen peroxide and iron doses and the effect of the presence of radical scavengers. RESULTS AND DISCUSSION: It was observed that the 4-chlorophenol degradation efficiency decreased with increasing concentration and was independent of the initial solution pH in the UV process. 4-chlorophenol oxidation efficiency for an initial concentration of 100 mgl(-1) was around 89% after 300 min of irradiation in the UV process and no mineralization was achieved. The efficiency increased to > 99% with the UV/H2O2 process in 60 min of irradiation, although mineralization efficiency was still around 75% after 300 min of reaction time. Although the H2O2/4-CP molar ratio was kept constant, increasing initial 4-chlorophenol concentration decreased the treatment efficiency. It was observed that basic pHs were favourable in the UV/H2O2 process. The results showed that the photo-Fenton process was the most effective treatment process under acidic conditions. Complete disappearance of 100 mgl(-1) of 4-chlorophenol was achieved in 2.5 min and almost complete mineralization (96%) was also possible after only 45 min of irradiation. The efficiency was negatively affected from H2O2 in the UV/H2O2 process and Fe2+ in the photo-Fenton process over a certain concentration. The highest negative effect was observed with solutions containing PO4 triple ions. Required reaction times for complete disappearance of 100 mgl(-1) 4-chlorophenol increased from 2.5 min for an ion-free solution to 30 min for solutions containing 100 mgl(-1) PO4 triple ion and from 45 min to more than 240 min for complete mineralization. The photodegradation of 4-chlorophenol was found to follow the first-order law. CONCLUSION: The results of this study showed that UV irradiation alone can degrade 4-CP, although at very slow rates, but cannot mineralize the compound. The addition of hydrogen peroxide to the system, the so-called UV/H2O2 process, significantly enhances the 4-CP degradation rate, but still requires relatively long reaction periods for complete mineralization. The photo-Fenton process, the combination of homogeneous systems of UV/H2O2/Fe2+ compounds, produces the highest photochemical elimination rate of 4-CP and complete mineralization is possible to achieve in quite shorter reaction periods when compared with the UV/H2O2 process. RECOMMENDATIONS AND OUTLOOK: It is more cost effective to use these processes for only purposes such as toxicity reduction, enhancement of biodegradability, decolorization and micropollutant removal. However the most important point is the optimization of the reaction conditions for the process of concern. In such a case, AOPs can be used in combination with a biological treatment systems as a pre- or post treatment unit providing the cheapest treatment option. The AOP applied, for instance, can be used for toxicity reduction and the biological unit for chemical oxygen demand (COD) removal.