Oxidation of aqueous sulfide solutions by dioxygen Part I: Autoxidation reaction
Oxidation of aqueous sulfide solutions by dioxygen Part I: Autoxidation reaction
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DOI：
10.1002/ceat.270200705
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发表时间：
1997-09
影响因子：
2.1
通讯作者：
Holger Fischer;G. Schulz-Ekloff;D. Wöhrle
中科院分区：
文献类型：
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作者：
Holger Fischer;G. Schulz-Ekloff;D. Wöhrle
研究了在初始硫化物浓度为1~100 mM、pH为9和14的条件下，氧气对硫化物水溶液的自氧化作用。二硫化物作为一种初级中间体，通过自催化生成多硫化物来促进硫化物的氧化。这一假设得到了在pH升高时观察到的过程加速的支持，这有利于二硫化物的存在，而不是硫的存在。最终的反应产物硫代硫酸盐和硫酸盐被认为是高度不稳定的中间体多硫代硫酸盐在平行反应路径上水解的结果，假设α(硫酸盐)和β(硫代硫酸盐)位置的硫链断裂的可能性对选择性负责。考虑到所有的实验观察，提出了一个反应方案。
The autoxidation of aqueous sulfide solutions by dioxygen is studied at pH 9 and 14 and at initial sulfide concentrations between 1 and 100 mM. Disulfide as a primarary intermediate is proposed to enhance the sulfide oxidation by autocatalytically forming polysulfies. The postulate is supported by the observed acceleration of the process at increasing pH favoring the presence of disulfide rather than that of sulfur. The final reaction products thiosulfate and sulfate are proposed to result from the hydrolysis of the highly instable intermediate polythiosulfite in parallel parallel reaction pathways, assuming probabilities for breaking the sulfur chain at the α (sulfate) and β (thiosulfate) positions to be responsible for the selectivity. A reaction scheme is proposed, considering all experimental observations.