Seperation of orthonitrotoluene from mixture of mononitrotoluene isomers by distillation and crystallization

Mononitrotoluene isomers are important main products that are produced as a mixture inthe nitration of toluene. Distillation and crystallization are the effective methods forseparation of mononitrotoluene isomers. In this paper, at first, the different methods ofmononitration of toluene and the properties of produced mononitrotoluene isomers havebeen reviewed. Then, separation of orthonitrotoluene from a mixture of mononitrotoluene isomers by simple distillation and crystallization processes have been studied experimentally. The results show that the maximum separation of orthonitrtoluene by crystallization doesnt exceed 76% whereas distillation can separate orthonitrotoluene up to 95%. Thus, distillation can separate orthonitrotoluene more effective than crystallization and is proper process for separating of orthonitrotoluene from the mixture of mononitrotoluene isomers.