XIANG Xiaofeng, ZHANG Xiangyu, WANG Zhichao, et al. Comparative study on performance of catalysts for urea hydrolysis[J]. Thermal power generation, 2023, 52(1): 105-110.
XIANG Xiaofeng, ZHANG Xiangyu, WANG Zhichao, et al. Comparative study on performance of catalysts for urea hydrolysis[J]. Thermal power generation, 2023, 52(1): 105-110. DOI: 10.19666/j.rlfd.202206136.
尿素水解催化剂性能比较研究
摘要
为筛选出高活性的尿素水解催化剂,利用间歇反应釜和连续操作中试装置,对尿素催化水解反应的动力学和热力学特性进行了研究,并比较了不同催化剂对水解反应温度、能耗和变负荷响应时间的影响。结果表明:添加催化剂能够降低水解反应的活化能(液态磷酸氢二铵活化能为65.3 k J/mol、固体氧化铝活化能为52.9 k J/mol),并提高尿素转化率;添加催化剂能够提高水解反应速率,降低水解反应温度;在连续操作反应器中,固体氧化铝催化剂存在分布不均、接触不充分的问题,导致催化活性下降;催化水解的产氨能耗仅比普通水解降低约1%~3%,添加磷酸氢二铵和氧化铝催化剂未减小水解器的变负荷响应时间。
Abstract
In order to select high activity catalysts for urea hydrolysis
the kinetic and thermodynamic characteristics of urea catalytic hydrolysis reaction were studied by using batch reactor and continuous operation pilot plant
and the effects of different catalysts on hydrolysis reaction temperature
energy consumption and variable load response time were compared. The results show that
the activation energy of the hydrolysis reaction can be reduced by adding catalyst(the activation energy of the liquid diammonium hydrogen phosphate is 65.3 kJ/mol
and that of the solid alumina is 52.9 kJ/mol)
and the urea conversion can be improved. The addition of catalyst increases the hydrolysis reaction rate and decreases the hydrolysis reaction temperature. Due to uneven distribution and insufficient contact
the catalytic activity of solid alumina catalyst decreases in the continuous operation reactor.The energy consumption of ammonia production by catalytic hydrolysis is about 1%~3% lower than that of ordinary hydrolysis
and the response time of hydrolyzer changing load is not shortened by adding diammonium phosphate and alumina catalyst.