论文部分内容阅读
用玻璃流动循环反应器研究了Bi_（1.5）Fe_（3.0）Ni_（4.5）Co_1Cr_（0.5）Mo_（12）K_（0.3）（原子比）氧化物催化剂（SiO_2载体）上的丁烯-2氧化脱氢动力学,发现丁烯转化速度对丁烯及氧的反应级数m及n与温度及反应物浓度有关,而且m+n≈1。 根据Redox稳态机理可认为: ①催化剂被丁烯还原的速度与还原态催化剂再氧化的速度达到稳态。 ②丁二烯在催化剂的氧化态表面部分上可逆吸附起了阻碍丁烯转化的作用,并导出速度方程为: 计算出催化剂还原步骤的活化能E_1=4.53kcal/g-mol,催化剂再氧化步骤的活化能E_2=21kcal/g-mol（>400℃）及60kcal/g-mol（<400℃）,E_2在400℃附近转折。当丁二烯阻碍作用不显著时（相对于丁烯,丁二烯分压较小,或反应温度较高）方程可以简化为 本文还对常见的钼系催化剂的丁烯转化的活化能发生转折的原因进行了讨论。
The butene-2 oxidation on a Bi 1.5 Fe 3.0 Ni 4.5 Co 1 Cr 0.5 Mo 12 K 0.3 atomic ratio oxide catalyst (SiO 2 support) was investigated by using a glass flow reactor. Dehydrogenation kinetics found butene conversion rate of butene and oxygen reaction series m and n and temperature and reactant concentration, and m + n ≈ 1. According to the Redox steady-state mechanism, it can be considered that: (1) the rate at which the catalyst is reduced by butylene and the rate at which the reduced catalyst reoxidizes reaches the steady state. ② The reversible adsorption of butadiene on the oxidized surface of the catalyst played an obstructing effect on the conversion of butene, and the derivation of the velocity equation was: Calculate the activation energy E_1 = 4.53kcal / g-mol of the catalyst reduction step, the catalyst reoxidation step The activation energies E_2 = 21 kcal / g-mol (> 400 ℃) and 60 kcal / g-mol (<400 ℃). E_2 turns around 400 ℃. When the impeding effect of butadiene is not significant (relative to butene, the partial pressure of butadiene is smaller or the reaction temperature is higher), the equation can be simplified as the transitional activation energy of butene conversion of common molybdenum-based catalysts The reason is discussed.