Patent ID: 8269049
Filing Date: 2012-09-18
Classification: C07C

Abstract:
1. A method of fabricating diethylene-glycol tert-butyl ether (DEGtBE) using isobutylene (IB = ) and diethylene glycol (DEG), comprising steps of: (a) obtaining DEG and IB (b) processing said glycol ether mixture through a first stage of vacuum distillation then a second stage of vacuum distillation, said first stage being a low vacuum water extraction distillation to separate octane and a byproduct of diethylene-glycol di-tert-butyl ether (DEGDtBE), wherein said first stage has a pressure between 50 and 500 torr and a temperature between 50 and 150° C.; and wherein water added in said first stage has a weight ratio to said glycol ether mixture between 0.1 and 5.0, said second stage being a high vacuum distillation to separate un-reacted DEG and a product of DEGtBE, wherein said second stage has a pressure between 0.1 and 10 torr and a temperature between 50 and 150° C.; and (c) recycling said byproduct of DEGDtBE separated in said first stage into said reactor to process a transetherification with said DEG, wherein said DEGDtBE has a weight ratio to said DEG between 0.002 and 1.0.