Effect of Dilute Acid and Alkali Pretreatments on the Catalytic Performance of Bamboo-Derived Carbonaceous Magnetic Solid Acid

Yikui Zhu,Shaolong Sun,Aimin Wu,Jiawei Huang,Huiling Li

doi:10.3390/catal9030245

Abstract

Lignocellulose is a widely used renewable energy source on the Earth that is rich in carbon skeletons. The catalytic hydrolysis of lignocellulose over magnetic solid acid is an efficient pathway for the conversion of biomass into fuels and chemicals. In this study, a bamboo-derived carbonaceous magnetic solid acid catalyst was synthesized by FeCl3 impregnation, followed by carbonization and –SO3H group functionalization. The prepared catalyst was further subjected as the solid acid catalyst for the catalytic conversion of corncob polysaccharides into reducing sugars. The results showed that the as-prepared magnetic solid acid contained –SO3H, –COOH, and polycyclic aromatic, and presented good catalytic performance for the hydrolysis of corncob in the aqueous phase. The concentration of H+ was in the range of 0.6487 to 2.3204 mmol/g. Dilute acid and alkali pretreatments of raw material can greatly improve the catalytic activity of bamboo-derived carbonaceous magnetic solid acid. Using the catalyst prepared by 0.25% H2SO4-pretreated bamboo, 6417.5 mg/L of reducing sugars corresponding to 37.17% carbohydrates conversion could be obtained under the reaction conditions of 120 °C for 30 min.

Highlights

The depletion of fossil fuel reserves and climate change issues have raised concerns about renewable petroleum alternatives with the increment of global energy demand [1,2]
The results showed that the prepared catalyst exhibited high catalytic activity for the conversion of corn straw into levulinic acid, and the most favorable values of catalyst dosage, hydrolysis temperature, hydrolyzation duration, and the maximum yield of LA were 3 g, 249.66 ◦ C, 67.3 min, and 23.17%, respectively [15]
It was found that arabinose was the secondary sugar constituent in the liquid fractions, and the yield of glucose was much lower than that of the former two. These results indicated that the dilute acid pretreatment mainly promotes the dissolution of hemicellulose rather than cellulose

Summary

Introduction

The depletion of fossil fuel reserves and climate change issues have raised concerns about renewable petroleum alternatives with the increment of global energy demand [1,2]. Biomass has received increasing attention in recent decades due to it being widespread, abundant, diverse, and inexpensive. It has been intensively investigated as a highly sustainable carbon-containing source for the production of bioplatform molecules and biochemicals. The conversion of lignocellulosic biomass to useful chemicals and biofuels via green and efficient approaches is one of the most popular topics in recent years [3]. Problems such as its high pretreatment cost and difficulty in catalyst recovery hinder their utilization. The development of new reaction techniques, including novel catalysts, novel pretreatment methods, or reaction media, is crucial for biomass-to-bioenergy industries [4]

Methods

Results

Conclusion