The mechanism of Mn2+-induced alkaline peroxide decomposition was studied. It was found that during the decomposition, a steady state of Mn3+ concentration was attained until the hydrogen peroxide concentration became zero. At zero hydrogen peroxide concentration, the Mn 3+ concentration increased to a maximum, then decreased due to hydrolysis to form MnO2. Removal of O2 from the system by N 2-purge slowed down the rate of decomposition, and the rate of decomposition was the same whether manganese was added as Mn2+ or Mn 3+. Based on these observations a mechanism for Mn2+-induced peroxide decomposition was proposed.
Manganese dioxide is one of the stable oxidation states of manganese. The catalytic activity of MnO2 and Mn2+ were compared and it was found that Mn2+ was more reactive than MnO 2 in decomposing hydrogen peroxide. The rate of peroxide decomposition was higher with MnO2 in powder form than in particulate form. The addition of stabilizers such as EDTA, DTPA and MgSO4 and Na 2SiO3 slowed down the redox cycle due to the formation of stable complexes. A mechanism for MnO2-induced peroxide decomposition was proposed.
It was demonstrated that the Mn-induced peroxide decomposition can be stopped when sodium silicate is used in combination with precipitated calcium carbonate. The potential to decrease peroxide decomposition was also investigated by adding zeolites to the silicate based peroxide system. The results show that the combined effect of zeolites and sodium silicate was more effective than sodium silicate alone in decreasing the Mn-induced peroxide decomposition. Two types of zeolites, X and Y were studied.
The Mn2+-induced peroxide decomposition in a magnesium hydroxide system using commercial magnesia slurry was studied. The results showed that the peroxide decomposition occurs under the bleaching conditions, as a result of impurities especially, manganese. Similar to the conventional sodium hydroxide based process, sodium silicate or DTPA can effectively decrease the Mn-induced peroxide decomposit
研究了锰离子诱导碱性过氧化分解的机理。结果表明，在分解过程中，Mn3+的浓度趋于稳定，直至过氧化氢浓度为零。在零过氧化氢浓度下，Mn 3+浓度上升到最大值，然后由于水解生成MnO2而下降。n2吹扫去除系统中的O2减慢了分解速度，无论锰是作为Mn2+还是Mn 3+加入，分解速度都是一样的。在此基础上提出了Mn2+诱导过氧化氢分解的机理。
二氧化锰是锰的一种稳定氧化态。比较了MnO2和Mn2+的催化活性，发现Mn2+分解过氧化氢的活性高于MnO2。粉末形式的二氧化锰的过氧化分解速率高于颗粒形式的二氧化锰。EDTA、DTPA、MgSO4和na2sio3等稳定剂的加入会形成稳定的配合物，从而减缓氧化还原循环。提出了二氧化锰诱导过氧化氢分解的机理。
结果表明，硅酸钠与沉淀碳酸钙混合使用可有效抑制mn诱导的过氧化物分解。通过在硅酸盐基过氧化物体系中加入沸石，研究了降低过氧化物分解的可能性。结果表明，沸石与硅酸钠的联合作用比单用硅酸钠更能有效地抑制锰的过氧化分解。研究了X和Y两种类型的沸石。
研究了用工业氧化镁浆料在氢氧化镁体系中Mn2+诱导的过氧化氢分解。结果表明，在漂白条件下，由于杂质尤其是锰的存在，会发生过氧化物分解。与传统的*工艺类似，硅酸钠或DTPA可以有效地减少mn诱导的过氧化物分解
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