石油钻井过程硫化氢污染和化学控制技术的研究与发展

根据硫化学的基础理论,分析和探讨了石油钻井过程硫化氢污染产生原因和化学控制原理,评述了硫化氢化学控制技术的研究与发展状况     

气中电晕放电对水中苯酚的氧化

讨论了一种新的去除水中有害有机分子的方法：在水溶液中形成低温等离子体电晕放电，产生具有化学活性的粒子扩散到水中，氧化水中的有机物，在本实验中用的是苯酚。实验测量了这种情况下的脉冲电晕放电的电压和电流波形图，讨论了自由基捕获剂的存在对溶液COD的影响和pH值对降解率的影响，并用气相色谱仪在吸收波长为210nm处测定脉冲电晕放电处理后的苯酚溶液的色谱图。     

甲醛清除剂净化效果的实验舱测试和分析

为了对市售被动式室内空气净化产品的净化效果有深刻具体的认识,选择销售份额较大的4种甲醛清除剂进行实验舱测试。结果表明:(1)甲醛清除剂对甲醛的净化过程均随时间呈对数衰减,可见甲醛浓度越高,甲醛清除剂对甲醛的净化速率越快。(2)不同的甲醛清除剂的净化速率都有一定差异,即使24h净化率均在90%以上的甲醛清除剂,净化速率也不同,净化率达到90%以上所需要的实际时间可相差数倍。(3)《室内空气净化功能涂覆材料净化性能》(JCT 1074—2008)中对甲醛清除剂根据其对污染物24h的净化率进行了分级,消费者可据此对净化产品的优劣有初步判断。而净化速率和饱和净化量则可在消费者购买甲醛清除剂时起到更具体和明确的指导作用,并可在消费者具体使用时,根据饱和净化量,对甲醛清除剂用量和甲醛清除剂持续作用时间有初步的判断。     

Reactive oxygen species metabolism during the cadmium hyperaccumulation of a new hyperaccumulator Sedum alfredii （Crassulaceae）

Sedum alfredii Hance, a newly discovered hyperaccumulator, could serve as a good material for phytoremediation Cd polluted sites. Malondialdehyde (MDA), reactive oxygen species (ROS) and antioxidases (catalase (CAT); superoxide dismutase (SOD); peroxidase (POD)) in the leaf were determined when S. alfredii was treated for 15 d with various CdCl2 concentrations ranging from 0 to 800 μmol/L. The results showed that the production rate of 2′,7′-dichlorofluorescein (DCF), which is an indicator of ROS level, reached up to the maximum at 400 μmol/L CdCl2 and then declined with the increase of CdCl2 concentration, while MDA accumulation tended to increase. CAT activity was significantly inhibited at all tested CdCl2 concentrations and SOD activity was sharply suppressed at 800 μmol/L CdCl2. However, the enhancement of POD activity was observed when CdCl2 concentration was higher than 400 μmol/L. In addition, its activity increased when treated with 600 μmol/L CdCl2 for more than 5 d. When sodium benzoate, a free radical scavenger, was added, S. alfredii was a little more sensitive to Cd toxicity than that exposed to Cd alone, and the Cd accumulation tended to decline with the increase of sodium benzoate concentration. It came to the conclusions that POD played an important role during Cd hyperaccumulation, and the accumulation of ROS induced by Cd treatment might be involved in Cd hyperaccumulation.     

活性炭纤维电极法处理印染废水的应用研究

采用新型催化电极处理了１８种水溶性及水不溶性染料液，并应用于数种实际扎染残液的处理，脱色率可达到９５％￣１００％，ＣＤＣｃｒ去除率达到４０％￣７０％。初步探讨了该电化学处理系统的反应机理，推论整个处理为吸附，自由基聚合和絮凝反应相结合的过程。     

硫化氢捕消剂清除硫化氢效果研究

硫化氢气体是高毒性气体,当其发生泄漏事故时将产生严重危害。目前,应对硫化氢泄漏事故的方法较少,主要为消防水喷淋和人员疏散,不能完全消除硫化氢的危害。针对硫化氢气体的特点,研制了在泄漏事故中用于清除硫化氢气体的捕消剂。硫化氢捕消剂为干粉状的,由吸附载体、反应组分和疏水组分组成。当发生硫化氢泄漏时,将捕消剂喷洒在泄漏源周围的空气中,使捕消剂与硫化氢充分接触反应以降低危害程度和范围。清除硫化氢实验结果表明,硫化氢捕消剂能够有效地清除泄漏在空气中的硫化氢气体。     

Application of percarbonate and peroxymonocarbonate in decontamination technologies

Sodium percarbonate (SPC) and peroxymonocarbonate (PMC) have been widely used in modified Fenton reactions because of their multiple superior features, such as a wide pH range and environmental friendliness. This broad review is intended to provide the fundamental information, status and progress of SPC and PMC based decontamination technologies according to the peer-reviewed papers in the last two decades. Both SPC and PMC can directly decompose various pollutants. The degradation efficiency will be enhanced and the target contaminants will be expanded after the activation of SPC and PMC. The most commonly used catalysts for SPC activation are iron compounds while cobalt compositions are applied to activate PMC in homogenous and heterogeneous catalytical systems. The generation and participation of hydroxyl, superoxide and/or carbonate radicals are involved in the activated SPC and PMC system. The reductive radicals, such as carbon dioxide and hydroxyethyl radicals, can be generated when formic acid or methanol is added in the Fe(II)/SPC system, which can reduce target contaminants. SPC can also be activated by energy, tetraacetylethylenediamine, ozone and buffered alkaline to generate different reactive radicals for pollutant decomposition. The SPC and activated SPC have been assessed for application in-situ chemical oxidation and sludge dewatering treatment. The challenges and prospects of SPC and PMC based decontamination technologies are also addressed in the last section.