甲烷氧化合成甲醛反应研究

自制了３．５％的ＭｏＯ３／ＳｉＯ２催化剂，用常压固定床催化反应器进行了工艺研究。得出最佳反应温度为６５０℃，最佳反应时间为０．５～０．７ｓ，最佳ＣＨ４／Ｏ２比为１０～１４，最佳甲烷转化率为１７％，最佳甲醛收率为１２．１％，并提出了生成甲醛的反应途径。在高转化率下，甲醛的选择性降低，在高空时（即停留时间）下，甲烷的转化率增加，随ＣＨ４／Ｏ２比的增加，甲醛收率出现最佳值。

Study on oxidation of methane to formaldehyde

he process for synthesis of formaldehyde from methane has been studied under atmospheric pressure in a fixedbed with selfprepared catalyst of 3.5% MnO3/SiO2. It has been concluded that the optimum reaction temperature is 650℃;the optimum contact time is 0.5￣0.7 seconds;the optimum CH4/O2 ratio is 10￣14;the optimum conversion of CH4 is 17% and the optimum formaldehyde yield is 12.1%.The reaction route to formaldehyde has also been proposed.Under higher conversions,the selectivity to formaldehyde decreases and at higher space time,the conversion of methane increases.With the increase of CH4/O2 ratio,the optimum yield of fotmaldehyde emerges.