WOOD RESEARCH Volume 63, Number 4, 2018
Chenah May and Amrani Moussa

Chemical and structural analysis of lignocellulosic biomass of Ampelodesmos mauritanicus (diss) and Stipa tenacissima

Chemical composition, anatomical characteristics and cell wall structure of Ampelodesmos mauritanicus (Diss) and Stipa tenacissima (Esparto grass) fibers were analyzed. The results reveal the % (W/W) holocellulose content of Diss and Esparto grass was found to be 54.39 % and 51.8 %, respectively. Esparto grass had the greatest % (W/W) lignin content of 32.2 % while Diss had the last lignin content of 24.95 %. Estimation of %( W/W) extractives contents in Diss and Esparto-grass were observed to be 12.03 % and 13.5 % in that order. According to XRD data, Diss showed, as expected, a lower crystallinity index (CI) 52.5 % when compared to Esparto grass samples 55.2 %. The results of the thermal decomposition of natural fibers are shifted to higher temperatures with increasing the cellulose crystallinity. Based on the results of the chemical composition of Diss and Esparto grass, it was confirmed that straw is rich in cellulosic fibers and, therefore, a valuable raw material for the paper and manufacture industry.

WOOD RESEARCH Volume 65, Number 6, 2020
Chenah May and Amrani Moussa

Optimisation of acid hydrolysis in ethanol production from Ampelodesmos mauritanicus (Diss)

In this work, statistical modeling and optimization of hydrolyzate from Ampelodesmos mauritanicus (Diss) using 1.5% sulfuric acid hydrolysis was carried. A central composite design (CCD) model was used to study the influence of reaction temperature (70°C to 110°C), ratio (5% to 15%, w/v), and reaction time (60 to 180 min). Reducing sugars, pH, proteins, lignin, ash content and the elements minerals composition were determined. Optimized reducing sugars yield of 0.249 g.g-1 of dry weight was obtained for reaction time of 180 min, reaction temperature of 110°C and ratio 5% (w/v). Therefore, this study tests the production of bioethanol from pure Diss hydrolyzate by the yeast Saccharomyces cerevisiae ATCC 9763. This strain showed a consumption of 67.6% of reducing sugars available (25 g.L-1), which made it possible to obtain ethanol yield per consumed sugar 0.33 g.g-1.