Catalytic Synthesis of Glycerol tert-Butyl Ethers as Fuel Additives from the Biodiesel By-Product Glycerol

Rui Huang,Eui Yong Kim

doi:10.1155/2015/763854

Abstract

Glycerol is a major by-product in the biodiesel production process. Every 100 kg of biodiesel produced generates approximately 10 kg of crude glycerol. As the biodiesel industry has expanded rapidly in recent years, finding new uses of the excess crude glycerol is important. Many studies have examined alternative uses of crude glycerol. One of them is the use of glycerol derivatives, such as glycerol tert-butyl ethers as fuel additives. In this paper, the etherification kinetics of glycerol with tert-butyl alcohol to glycerol tert-butyl ethers was studied using an Amberlyst catalyst. The influences of the catalyst type and loading, reaction time, molar ratio, and temperature were investigated in detail.

Highlights

Biodiesel is a renewable, clean-burning diesel replacement from biological sources that it is produced widely around the world
The influence of the catalyst type and loading, reaction time, molar ratio, and temperature on the etherification reaction was investigated in detail by calculating the conversion of glycerol and the selectivity of glycerol tertiary butyl ethers (GTBEs)
The catalyst loading was found to have some influence on the etherification reaction

Summary

Introduction

Clean-burning diesel replacement from biological sources that it is produced widely around the world. Glycerol tertiary butyl ethers (GTBEs) are excellent additives with large potential for diesel and biodiesel reformulation. Tert-butyl alcohol (TBA) is more attractive for producing GTBE by the glycerol etherification reaction in a solid-liquid catalytic process [10]. Diesel-blending agents whereas the higher ethers of glycerol, such as 1,3-di-tert-butoxy-2-propanol (DTBG1), 1,2-ditert-butoxy-3-propanol (DTBG2), and 1,2,3-tri-tert-butoxy2-propane (TTBG), have good solubility in biofuel, a high flash point, low water affinity, and negligible cetane reduction, making them a potential candidate fuel additive [10]. Amberlyst is a strongly acidic, sulfonic acid, macroreticular polymeric resin based on cross-linked styrene divinylbenzene copolymers It is used in catalytic processes including etherification reaction.

Experimental

Results and Discussion

Conclusions