Coproduction of xylose and biobutanol from corn stover via recycling of sulfuric acid pretreatment solution
- PDF / 769,937 Bytes
- 8 Pages / 595.276 x 790.866 pts Page_size
- 51 Downloads / 189 Views
ORIGINAL ARTICLE
Coproduction of xylose and biobutanol from corn stover via recycling of sulfuric acid pretreatment solution Jin‑Jun Dong1 · Bao‑Jian Ma1 · Yong‑Mei Liu2 · Hao Li1 · Lei Gong1 · Rui‑Zhi Han1 · Guo‑Chao Xu1 · Ye Ni1,3 Received: 23 July 2020 / Revised: 26 August 2020 / Accepted: 29 August 2020 © Jiangnan University 2020
Abstract Sulfuric acid was used in the pretreatment of corn stover to obtain xylose as a value-added by-product, and the pretreated corn stover (Pre-CS) was hydrolyzed to produce glucose for butanol fermentation. The aim of this work is to achieve high xylose accumulation and reduced wastewater by recycling the pretreatment solution. The pretreatment conditions were optimized as follows: 180 °C, 15 min, 1:7 solid–liquid ratio (w/w), 0.6% H 2SO4 (w/w, first batch)/0.9% H2SO4 (w/w, second and third batches), in which pretreatment solution was recycled for three times. Under above conditions, pretreatment solution containing 56.3 g/L xylose and 4.5 g/L glucose was obtained. Pre-CS residue was further hydrolyzed by cellulase to achieve 35.7–39.9 g/L glucose. The condensed corn stover hydrolysate was subjected to simultaneous detoxification and sterilization using 1% (w/w) activated carbon and then applied in butanol fermentation. The highest butanol titer of 9.5 g/L was obtained in 72 h. The results provide a practical approach for coproducing xylose and biobutanol from corn stover. Keywords Acid pretreatment · Recycle · Xylose · Butanol · Simultaneous detoxification and sterilization · Clostridium saccharobutylicum
Introduction Increasing environmental pollution and fluctuating petroleum prices have stimulated great interest in biofuels production. In the USA, 58.87 billion liters of ethanol was produced from corn in 2016 [1, 2]. Growing demand for “environmental-friendly” biofuels has driven increased food prices, even food shortage in many countries. Fermentation of lignocellulosic biomass is an attractive and feasible route to biofuels that supplements the fossil fuels [1, 3]. It has been estimated that 442 billion liters of bioethanol per year can be produced from lignocellulosic biomass all over the world [4]. Butanol has attracted increasing attentions as a biofuel, due to its excellent properties such as high energy * Ye Ni [email protected] 1
Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
2
School of Pharmacy, Taizhou Polytechnic College, Taizhou 225300, Jiangsu, China
3
Key Laboratory of Guangxi Biorefinery, Nanning 530003, Guangxi, China
density, low volatile and explosive, and miscible with gasoline in any proportion [5]. Corn stover is an abundant lignocellulosic biomass [6–9], with a global annual production of 0.95 billion tons [10]. However, pretreatment of corn stover is required to release sugars that can be utilized by microorganisms to produce biofuels [5, 8, 11]. Corn stover is composed of 37% cellulose and 19.8% xylan [12]. Various pretreatment method
Data Loading...
