过氧化氢氧化硫化钠的闭系动力学行为

摘要

系统研究了过氧化氢(H2O2)氧化硫化钠(Na2S)反应在封闭体系中的复杂动力学行为.通过固定两种反应物浓度,改变其中一种反应物浓度,考察了酸度、反应物浓度对硫沉淀的形成、准振荡现象的产生和反应速率的影响.结果表明:酸度越小,反应速率越慢,反应过程中产生的多硫离子被进一步氧化为无色 SO2-4;反之,在酸度足够大时,析出白色硫沉淀且不能被进一步氧化.H2O2浓度越大,反应速率越快,同时有利于硫的消耗.Na2S浓度越大,反应过程中产生的硫沉淀越少,反应速率也越慢.酸度、H2O2或 Na2S浓度在某一中间值时,产生明显的准振荡现象.该研究对于减少工业和城市废水中硫化物的污染提供了一种参考思路.%We systematically studied the complex dynamic behavior in the hydrogen peroxide-sodium sulfide reaction in a batch system.Through fixing the concentration of two reactants and changing the concentration of one reactant,we explored the effects of acidity and reactant concentration on the formation of sulfur precipitati-on,oligooscillation phenomenon,and reaction rate.The results indicate that the less the acidity is,the slower the reaction rate will be,and the produced polysulfide ions are further oxidized to colorless SO2-4.Otherwise,if the acidity is high enough,white elementary sulfur will precipitate out and cannot be further oxidized.The greater the concentration of hydrogen peroxide is,the faster the reaction rate will be,which benefits the consumption of sulfur.The greater the concentration of sodium sulfide is,the less the sulfur precipitation and the slower the re-action rate will be.When the acidity and the concentration of hydrogen peroxide or sodium sulfide are in mid-values,the system exhibits evident oligooscillation behavior.The study provides a reference thought for reduc-ing sulfide pollution in industrial and urban wastewater.