(401j) Recovery of Monosaccharides from Dilute Acid Corncob Hydrolyzate based on Nanofiltration Technology?Modeling and Optimization
AIChE Annual Meeting
2017
2017 Annual Meeting
Separations Division
Poster Session: Separations Division
Tuesday, October 31, 2017 - 3:15pm to 4:45pm
Nanofiltration is a high-efficiency technology to remove inhibitors and recover monosaccharides from the dilute acid lignocellulose hydrolyzates. In this study, the effect of feed pH, permeate flux and Na2SO4 concentration on the rejection of monosaccharides and inhibitors was firstly investigated. The results showed that the separation performance of carboxylic acids and furans from monosaccharides was optimal at pH 3. All the rejection of carboxylic acids and furans decreased with increasing Na2SO4 concentration, especially for carboxylic acids. Subsequently, donnan steric pore flow model coupled with mass balance (DSPM-MS model) was successfully applied to predict the rejection of solutes at different permeate flux. Based on the DSPM-MS model a parallel multi-objective optimization strategy was developed to select a reasonable permeate flux jv and operating time t, in which maximum total inhibitor remove efficiency Prinhibitor, maximum recovery rate of monosaccharides Ysugar and minimum water consumption EC were set as objective functions. The results showed that in the case of maximum Ysugar, more monosaccharides were recovered and less water was consumed as well. The optimal operating condition was consequently verified with the practical hydrolysate solutions. It had consumed about 35 min and 13L water to remove 95% inhibitors, meanwhile, 93.55% glucose, 90.75% xylose and 90.53% arabinose were recovered.In the end of this work, a batch column equipped with strong acid cation-exchange resins Sa-2 were used to recover monosaccharides from the hydrolysate. Using water as eluent, 95.37% of sulfuric acid and 94.87% of monosaccharides was recovered. This work demonstrated that nanofiltration combined with electrolyte exclusion chromatography could be a potential integrated process to recover monosaccharides and inorganic acids in the practical dilute acid corncob hydrolyzate.