Two alpha functions(BM,SRW) and three different mixing rules(MHV2,WS,HG) for the PR and RKS-EOS were investigated in the vapor-liquid equilibrium calculation of related binary systems for Fischer-Tropsch synthesis oil system.Furthermore,two different equations of states(EOS) of SR-POLAR and PC-SAFT,together with two activity coefficient equations of UNIF-DMD and UNIF-HOC were investigated.The results showed that various prediction methods had similar deviations for weakly polar systems.However,these method had different prediction abilities for other systems.UNIF-DMD,RKS-HG and RKS-MHV2 models gave more accurate prediction for non-associating strongly polar system,RKS-MHV2 and UNIF-HOC models showed the smallest deviation for associating strongly polar system containing water,UNIF-HOC and SR-POLAR models showed the smallest deviation for associating strongly polar system containing acids,and UNIF-HOC,SR-POLAR models showed the smallest deviation for other associating strongly polar systems,while RKS-MHV2 and RKS-HG took the second place.PC-SAFT model would bring big deviation for unsymmetrical system when binary parameters were lacking,but would give small deviation for all systems when binary parameters were available.
