还原沉淀法制备氧化锰及其燃煤助燃性能的研究

在常压下,以高锰酸钾为原料,与双氧水以及一定沉淀剂的反应来制取二氧化锰.以静态坩埚燃烧法,考察了不同沉淀剂、焙烧温度、反应温度、反应物配比对二氧化锰助燃性能的影响规律.结果表明:在反应中选取碳酸氢铵为沉淀剂时,氧化锰的助燃效率最高;随着氧化锰的焙烧温度以及反应温度的升高,氧化锰的助燃效率呈增大趋势;双氧水的用量也使氧化锰的性能发生变化,随着双氧水用量的增加,氧化锰的助燃性能也随之提高.二氧化锰最佳制备条件为:以0.05mol的高锰酸钾溶液为基准,30%的双氧水50mL,0.25mol/L的碳酸氢铵20mL,在50℃的水浴中反应3h,焙烧温度为500℃,此时二氧化锰使煤的燃烧效率提高了3%.

Preparation of Manganese Oxide by Reduction-precipitiation Method and its Performance as Coal Combustion Improver

At atmospheric pressure,manganese oxide was prepared by reduction-precipitiation method with potassium permanganate as raw material to interact with precipitant in the presence of hydrogen peroxide.By the static crucible method,the effects of different precipitating agent,calcination temperature and reactant ratio on the combustion properties of manganese oxide were studied.The restults show that when the ammonium bicarbonate was selected as precipitant in the reaction,higher promotion-combustion-efficiency(PCE) was found.The PCE were also found incresing with the incresing of manganese oxide calcination temperature and prepartion reaction temperature.With more hydrogen peroxide were added in the preparaton reaction,the PCE of manganese oxide were enhanced.The best conditions for preparing manganese dioxide were as fllows:A solution of 0.05 mol of potassium permanganate as a benchmark,30% hydrogen peroxide 50 mL,0.25 mol/L of ammonium bicarbonate 20 mL,water bath at 50 ℃,for 3 hours of reaction,calcination temperature at 500 ℃.The aboved manganese oxide was of 3% PCE.