Effect And Mechanism Of Surfactants On Enzymatic Hydrolysis Characteristics Of Peanut Shells

With the rapid development of globe economy, non-renewable energy fossil oil and gaswill be used up and environmental problem is increasingly serious. The issue of exploitingnew energy needs to be solved. Bioethanol from lignocellulosic biomass has renewable,environmentally friendly and cost-effective advantages. And lignocellulosic biomass is widelyavailable, abundant and inexpensive. Cellulosic ethanol is considered one way to solve theproblem of high input and low output, and there is growing interest in alternative uses oflignocellulosic biomass for energy applications.Cellulose is surrounded with hemicellulose and lignin, forming highly compact structurein the cell walls of lignocellulosic biomass. The highly compact structure impedes thecellulosic ethanol development. At present the issues of producing ethanol are how toeffectively destroy the complex structure of lignocellulosic biomass and how to increase theefficiency of enzymatic hydrolysis.Microwave-NaOH pretreatment of peanut shells and enzymatic hydrolysis in thepresence of surfactants were studied in this paper. And the mechanism of enhancedpretreatment and enzymatic hydrolysis by surfactants was explored.The factors of pretreatment were optimized by orthogonal test. The optional conditionswere: microwave power640W, heating time22min, CTAB concentration10%, mass fractionof sodium hydroxide1.75%and ratio of liquid to solid20:1. Compared to control sample, thereducing sugar yield was notably improved, and it revealed that the effect ofmicrowave-NaOH pretreatment in the presence of CTAB was enhanced.The optional conditions of enzymatic hydrolysis were studied by response surface tests.The optional conditions were: PEG6000addition1.92%, pH4.90, temperature of hydrolysis48.8°C and enzyme addition10.5IU/g. And the kinetic equation had been deduced accordingto the mechanism of hydrolysis of cellulose, and it was:t27954.93(9.4905-(90.07-[G])2)-103.9(854.8813-(90.07-[G])2). As a result, theconclusions provided a certain reference for research and improved the hydrolysis efficiency.The active effect of CTAB on microwave-NaOH pretreatment of peanut shells wasverified by Fourier transform infrared (FTIR) analysis, scanning electron microscopy (SEM)and X-ray diffraction (XRD). And the mechanism of effect of CTAB on pretreatment wasdiscussed. The effect of PEG6000on stability and activity of cellulase as well as the maximalreaction rate and adsorption of cellulase were evaluated, and the mechanism of PEG6000on cellulase was investigated.