• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Hazardous Materials >Studies on dechlorination of DDT (1,1,1 -trichloro-2,2-bis(4-chlorophenyl)ethane) using magnesium/palladium bimetallic system
【24h】

Studies on dechlorination of DDT (1,1,1 -trichloro-2,2-bis(4-chlorophenyl)ethane) using magnesium/palladium bimetallic system

机译：镁/钯双金属体系对滴滴涕（1,1,1-三氯-2,2-双（4-氯苯基）乙烷）的脱氯研究

获取原文
获取原文并翻译 | 示例
       
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The aim of our investigation was to compare the rates of dechlorination of DDT using Mg~0/Pd~(4+) system in two different reaction phases, namely, water-acetone and 0.05% biosurfactant in water. Since palladium is expensive and its toxicity effects are not well known we also examined the reuse efficiency of Pd~0 immobilized on alumina for dechlorinating DDT. Studies on the dechlorination of DDT in water-acetone (1:1, v/v) and 0.05% biosurfactant phases revealed that the reaction followed second order kinetics and rate of reaction is dependent upon both initial concentrations of the target compound and Mg~0/Pd~(4+). The presence of acid enhanced the rate of reaction by providing protons and preventing passivation of metal that occurs due to deposition of magnesium hydroxide. GC-MS analyses revealed the formation of completely dechlorinated hydrocarbon skeleton of DDT namely, diphenylethane (DPE), as the end product in both reaction phases (water-acetone and 0.05% biosurfactant in water) thereby implying the removal of all five chlorine atoms (three alkyl and two aryl) of DDT. The optimum ratio of water and acetone to facilitate successful dechlorination reaction was found to be 9; 1. Results suggested that salt form (K_2PdCl_6) of palladium had higher potential to dechlorinate DDT as compared to pellet (Pd~0-alumina) form (efficiencies of 95 and 36%, respectively, for 100 ppm initial concentration of DDT). We noted that Pd~0-alumina pellets could be reused at least four times for successful dechlorination of DDT provided Mg~0 granules are present in sufficient quantity. Technical grade DDT (50 ppm) containing significant amounts of DDD was dechlorinated almost completely by the Mg~0/Pd~(4+) (10mg/0.2mg/ml) within 1 h in water-biosurfactant phase. Our studies reveal that Mg/Pd system is a promising option due to its high reactivity and its ability to achieve complete dechlorination of DDT. This bimetallic system may be useful for designing indigenous permeable barriers or reactors for the treatment of DDT contaminated water.
机译：我们的研究目的是比较Mg〜0 / Pd〜（4+）体系在水-丙酮和水中的0.05％生物表面活性剂两个不同反应阶段对DDT的脱氯速率。由于钯价格昂贵且其毒性作用尚不为人所知，因此我们还研究了固定在氧化铝上的Pd〜0对DDT脱氯的再利用效率。对DDT在水-丙酮（1：1，v / v）和0.05％生物表面活性剂相中的脱氯研究表明，反应遵循二级动力学，反应速率取决于目标化合物的初始浓度和Mg〜0 / Pd〜（4+）。酸的存在通过提供质子并防止由于氢氧化镁的沉积而发生的金属钝化来提高反应速率。 GC-MS分析表明，DDT的完全脱氯烃骨架即二苯乙烷（DPE）的形成是两个反应阶段（水-丙酮和水中的0.05％生物表面活性剂）的最终产物，从而暗示了所有五个氯原子的去除（三烷基和两个芳基）。为了促进成功的脱氯反应，水和丙酮的最佳比例为9； 1.结果表明，与小球状（Pd〜0-氧化铝）形式相比，钯的盐形式（K_2PdCl_6）具有更高的去氯滴滴涕的潜力（DDT初始浓度为100 ppm时，效率分别为95％和36％）。我们注意到，如果存在足够量的Mg〜0颗粒，Pd〜0-氧化铝颗粒可以重复使用至少四次以成功地对DDT进行脱氯。含有大量DDD的工业级DDT（50 ppm）在水生物表面活性剂相中1小时内几乎被Mg〜0 / Pd〜（4+）（10mg / 0.2mg / ml）完全脱氯。我们的研究表明，由于Mg / Pd系统具有较高的反应活性和实现DDT完全脱氯的能力，因此它是一个很有前途的选择。该双金属系统可用于设计用于处理DDT污染水的本地可渗透屏障或反应器。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号