Production of Bioethanol from Waste Paper

Abstract

The generation of biofuels from wastes forms an attractive solution towards both waste management and energy generation via bio-fuels. Newspaper, which is a cellulosic feed stock, is emerging as an attractive option for the production of bio-ethanol because of lower feedstock costs, higher potential for fossil fuel displacement and also there will be a reduction in greenhouse gas emission as compared to production of ethanol from food grains. Experimental studies have been carried out to optimize the pretreatment process for increasing the efficiency of enzymatic hydrolysis, the efficient conversion of cellulose to sugars from cellulose-degrading microorganisms and to convert the sugars released to ethanol by using fermentation process. Pre-treatment, hydrolysis, and fermentation are the steps involved in the production of bioethanol. The optimum glucose produced was 89.59 % yield at 80°C, 23 h, 1.76 % v/v with H2SO4pre-treatment and 58.02% yield at 23.6 h, 53°C, 0.5% w/v with NaOHpretreatment. The enzyme cellulase was used for hydrolysis process, which helped in converting the cellulose to sugars and was analysed using Dinitrosalicilic acid. Fermentation method is used for the production of ethanol by using waste paper in the presence of microorganism Pichiastipitis NCIM 3498. The yield was estimated by using HPLC and it is found to be 6.61 g/L for H2SO4pre-treated paper, 4.37 g/L for NaOHpre-treated paper and 3.42 g/L for untreated paper. Structural changes of waste paper before and after pre-treatment with H2SO4 and NaOH were further investigated through Fourier transformed infrared spectroscopy (FTIR) and X-ray diffraction (XRD).