Exploration of enhanced distillation techniques for dehydration of tert butyl alcohol

Abstract

Energy is the most fundamental entity to an economic system and indeed to all life. newlinePrimarily, harnessed from the non-renewable fossil fuels, which are depleting at a fast rate newlinethereby requires a transition towards renewable energy sources. The Bio-derived additives with newlinehigh content of di-ethers of glycerol are proposing alternatives that can be blend with diesel newlinebased fuel. A precursor to di-ethers production through etherification reaction requires a fuel newlinegrade/high purity tert-butyl alcohol (TBA). The industrial applicability of TBA is hindered by newlinethe formation of a minimum boiling azeotrope with water. Here, conventional distillation is newlinedifficult and often expensive for the product isolation and thereby calls for energy intensified newlineapproach. As a consequent step the present thesis explores an enhanced distillation technique, newlinei.e. extractive distillation for the dehydration of TBA. Different classes of entrainer for newlineextractive distillation are assessed based on their techno-economic value on the process. A newlinecomprehensive methodology is presented wherein the process design and optimization with newlinedifferent entrainers encapsulate the experimental feasibility studies as an additional step in the newlinedesign framework to reduce any inaccuracy which may occur due to imprecise property newlineprediction during the entrainer selection and ranking. newlineIn extractive distillation with conventional liquid solvent, a systematic entrainer newlinescreening and experimental phase equilibrium measurements were carried for the selected newlineentrainers (EG, TEG, TEEG and glycerol). The entrainer ranking and process design and newlineoptimization was based on the experimentally evaluated energy interaction parameters. newlineAmong the investigated, glycerol was found to be most suitable with lowest total annualized newlinecost with high capacity. The next class opted a saline entrainer, a combination of a liquid newlinesolvent (glycerol found