Optimization Study of Biomass Hydrogenation to Ethylene Glycol Using Response Surface Methodology

Poh Gaik Law,Noor Haida Sebran,Ashraf Zin Zawawi,Azlan Shah Hussain

doi:10.3390/pr8050588

Abstract

Statistical-based study using response surface methodology (RSM) was conducted to study the effects of process parameters towards biomass hydrogenation. Using Malaysian oil palm empty fruit bunches (EFB) fibres as feedstock, the central composite design (CCD) technique was employed and 18 runs were generated by CCD when four parameters (mass ratio of binary catalyst, hydrogen pressure, temperature and mass ratio of catalyst to feedstock) were varied with two center points to determine the effects of process parameters and eventually to get optimum ethylene glycol (EG) yield. RSM with quadratic function was generated for biomass hydrogenation, indicating all factors except temperature, were important in determining EG yield. Analysis of variance (ANOVA) showed a high coefficient of determination (R2) value of >0.98, ensuring a satisfactory prediction of the quadratic model with experimental data. The quadratic model suggested the optimum EG yield should be >25 wt.% and the EG yield results were successfully reproduced in the laboratory.

Highlights

Using catalysts and agricultural lignocellulosic waste as feedstock, bio-based ethylene glycol (EG)could be produced
1.2% Ru/MC coupling was used with tungstic acid at a mass ratio of 2:1, maximum EG yield was achieved at 58.5% [2]
Alkaline pre-treatment managed to give 54.31% delignification efficiency and comparatively increased cellulose content to 62.31% from its initial cellulose content before alkaline pre-treatment. These results further confirmed the empty fruit bunches (EFB) delignification model developed by Zawawi et al was functional and the model developed was comparable with the pre-treatment work done by other groups of researchers that had a delignification efficiency between 10% and 71% [34,36,37,38,39,40,41,42]

Summary

Introduction

A research team in China filed a patent in 2008 indicating ethylene glycol could be produced from cellulose under a catalytic hydrogenation process [1]. Glucose or biomass as feedstock, extensive work has been carried out by researchers around the world who have studied the effect of process parameters to EG yield [2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25].

Methods

Results

Conclusion