PHASE PLANE ANALYSIS OF NONLINEAR ODE''''S IN REACTION ENGINEERING

The application of phase plane analysis is extended on the basis of the authors' previous paper in which this approach was suggested to analyze a set of first-order nonlinear ODE's. The main point of phase plane analysis is the temporary elimination of non-intrinsic variables e.g. t and z, involved in the ODE sets which are commonly encountered in the course of solving reaction engineering problems. Two types of nonlinear ODE's i.e. a set of firstorder ODE's and a set of second-order ODE's, which depict the phenomena of parametric sensitivity and multiplicity of reactors, respectively, are explained. The concept of iso-parameter lines of phase planes is taken advantage of, and, as a methodology, emphasis has been placed on the flexibility of phase plane analysis.     

复杂反应系统的选择性和动力学:催化重整和催化裂化(摘要)

在石油化学领域中,常常碰到多种分子偶联的复杂化学反应体系,如石油馏分的催化裂化和催化重整就是这类反应体系。从宏观动力学角度来分析,往往可以简化为单分子间的一级或拟一级反应。但对偶联反应要根据各分子浓度随时间的变化测定结果来计算速度常数是困难的。为了解决这个问题,就要用矩阵方法将这个偶联的反应体系转换成一个等价的非偶联体系,这样就可以用电子计算机将各分子间的反应速度常数及反应选择性计算出来。这种新方法于六十年代提出后,现在已在工业部门获得广泛应用。例如,美孚石油公司曾用这种方法计算过300种分子(汽油馏分)间的复杂反应过程,发