The Impact of Ultrasound Pretreatment on the Enzymatic Hydrolysis of Cellulose from Sugar Beet Shreds: Modeling of the Experimental Results

This article investigates the impact of ultrasound as pretreatment for enzymatic hydrolysis of cellulose from sugar beet shreds and uses modeling of the experimental results. Ultrasound pretreatment with different power input, duration, duty cycle, and solids load was applied to sugar beet shreds. Ultrasound under investigated conditions provided substrates with different characteristics. At applied conditions, ultrasound caused up to 28% material solubilization while cellulose recovery was approximately 90%. Pretreated substrates had multiple times higher values of water retention (WRV) than untreated one. Ultrasound pretreated sugar beet shreds were more susceptible to cellulases adsorption than the untreated ones having 1.4 to 15 times higher maximum adsorption capacity (sigma). Statistical modeling of the results of enzymatic hydrolysis revealed that parameters with significant influence on the reducing sugars yield were interaction between sigma and cellulose recovery, then sigma and WRV as mutually independent parameters, as well as interaction between WRV and sigma. The highest achieved yield of cellulose hydrolysis was 3.7 times higher than that obtained with untreated sugar beet shreds and it amounted approximately 780 mg/g cellulose. (c) 2017 American Institute of Chemical Engineers Environ Prog, 36: 1164-1172, 2017