Fuels and Chemicals from Lignocellulosic Biomass: An Integrated Biorefinery Approach

Abstract

Several efforts have been made during the last three decades to develop successful lignocellulose-based technologies for the production of fuels and chemicals. However, such technologies still seemed to be emerging, because of the high technical risks involved and huge capital investments. This paper describes a holistic approach toward utilization of sugar cane bagasse as lignocellulosic feedstock into fuel (ethanol), chemical (furfural), and energy (electricity), using a biorefinery approach instead of co-generation. The proposed scheme could be integrated with existing sugar or paper mills, where the availability of biomass feedstock is in abundance. Fermentable sugar components (xylose and glucose) from sugar cane bagasse have been extracted employing acid hydrolysis and enzymatic saccharification. Recovery and reuse of saccharifying enzyme was a major process advantage. The pentose fraction was efficiently utilized for yeast biomass generation and furfural production. High-temperature fermentation of a hexose stream by thermophilic yeast Kluyveromyces sp. IIPE453 (MTCC 5314) with cell recycle produced ethanol with an overall yield of 88% ± 0.05% and a productivity of 0.76 ± 0.02 g/L h–1. A complete material balance on two consecutive process cycles, each starting with 1 kg of feedstock, resulted in an overall yield of 366 mL of ethanol, 149 g of furfural, and 0.30 kW of electricity.

Enhancement of Photocatalytic Oxidation of Glucose to Value-Added Chemicals on TiO2 Photocatalysts by A Zeolite (Type Y) Support and Metal Loading

“…From a previous study of platform molecules, gluconic acid was found to be the one of important building blocks for the medical, foodstuff, and fuel industries, which can be produced via oxidation of glucose [2]. Chemicals can be generally produced from many technologies, such as fermentation [3] and the Fischer-Tropsch process [4]. Conversely, they required high-energy consumption, operated under high-pressure-temperature condition, and there are many steps to produce chemicals.…”

Biochemical Production and Separation of Carboxylic Acids for Biorefinery Applications

“…In fact, reports from a 2004 study indicated that existing forestry reserves around the world had the capacity to supply up to 9.2 billion tons of oil equivalents, which is enough to supply around 82% of the global energy demand [7]. Several routes have been developed for the conversion of lignocellulosic biomass to biofuels such as pyrolysis [8], gasification [9], liquefaction [10], and a combination of comparatively low-severity thermochemical pretreatment followed by concerted action of enzymes and microorganisms [11]. While each of these technologies has different merits and problems, as discussed in several reviews on their respective fields, the current state of the art in the latter platform is usually considered more specific and cost-efficient and results in high-value byproduct streams [2].…”

Lipids of Rhodotorula mucilaginosa IIPL32 with biodiesel potential: Oil yield, fatty acid profile, fuel properties

“…2.1 | Yeast strain, growth substrate, and pretreatment Sugarcane bagasse procured locally from the sugar mill in Dehradun (India) was used as a growth substrate for the cultivation of R. mucilaginosa IIPL32 (MTCC 25056). The pentose-rich fraction was obtained after dilute sulfuric acid hydrolysis employing steam and H 2 SO 4 (4%, w/w) in 1:10 solid-liquid ratio (90 min, 120°C; 4 bar pressure) followed by over-liming and clarification [18]. The bagasse hydrolyzate (xylose, 40 g L −1 ) was used as a shake flask fermentation medium under nitrogen limiting conditions for yeast biomass production at 32°C.…”