Optimizing the Synthesis of Lignin Derivatives from <em>Acacia mangium </em>to Improve the Enzymatic Hydrolysis of Kraft Pulp Sorghum Bagasse

Abstract

The present study is aimed at optimizing the synthesis of Amphipilic lignin derivatives (A-LD) from the isolated lignin of A.mangium black liquor (BL), using the one and two step acid isolation method, and commercial lignin (LS) was used as comparison. The experimental design was conducted using Taguchi method, which consisted of four parameters and two level factors, with reference to the matrix orthogonal array, L8, including temperature, reaction time, amount of polyethylene glycol diglycidylethers (PEGDE) and Kraft lignin (KL). Furthermore, the kraft pulp of sweet sorghum bagasse (SSB) was used as substrate in the enzymatic hydrolysis (NREL method), with addition of A-LD, whose functional group and surface tension were then characterised using ATR-FTIR and surface tension equipment. Conversely, an improvement in the reducing sugar yield (RSY) compared to the control was observed after adding various A-LDs to the substrate during enzymatic hydrolysis. This product was more prospective for L2S than others products under milder circumstances, due to the fact that it possesses the lowest surface tension. Also, Taguchi analysis demonstrated the treatment at 60 °C for 1 h with 3.0 g and 1.0 g of PEDGE and lignin, respectively as the optimum condition, while the amount of lignin present was included as a factor with the propensity to significantly affect A-LD L1S and LS. Therefore, it was established that the A-LDs from A. mangium kraft lignin require milder synthesis conditions, compared to other existing methods and despite the differences in optimum experimental condition for L2S and LS, the functional groups in the IR spectra possessed very identical characteristics. ©2020. CBIORE-IJRED. All rights reserved

Design and performance of amphiphilic lignin derivatives in enzymatic hydrolysis of sweet sorghum bagasse for bioethanol production

“…The addition of A-LD in enzymatic hydrolysis has been found to successfully increase the reducing sugar yield (RSY) of SSB kraft pulp up to 81%. Another study on the optimization of A-LD synthesis conditions also confirmed the beneficial effects of the RSY (Fatriasari et al 2020a). The lignin derivatives addition was effective to increase RSY on several pretreated biomass containing low lignin content (Fatriasari et al 2020b).…”

“…The precipitated lignin was stored in a freezer at −18 °C for 24 h and filtered by a technical paper filter. The lignin powder was obtained after drying the precipitate at 45 °C for 24 h. The A-LD was synthesized according to the optimization condition by Fatriasari et al (2020a). The lignin stock was prepared by dissolving 1 g of lignin in 50 mL NaOH (1 mol/L).…”

“…Lignin is one of major compounds in lignocellulosic material, after cellulose. In Indonesia, approximately 0.41 million tons per year of lignin is produced as a byproduct of unutilized black liquor in the pulp and paper industry (Fatriasari et al 2020a). The presence of lignin can interfere with enzyme adsorption, so the optimal release of sugars content cannot be achieved during the hydrolysis process.…”

“…In this study, A-LD was synthesized using a set of optimized conditions and steps that were established in the authors' previous study (Fatriasari et al 2020a). Subsequently, response surface methodology (RSM) with Box-Behnken design (BBD) was used to identify the contribution of the three-level variables on the RSY as a response.…”

Lignin as an Active Biomaterial: A Review

“…Lignin is usually mixed with polyethylene to produce bio-surfactant. For instance, blending kraft-lignin with polyethylene glycol diglycidyl ethers (PEDGE) successfully enhanced enzymatic hydrolysis for bioethanol production, and the reducing sugar yield increased about 20% besides of lignin-derivative biosurfactant (Fatriasari et al 2018;Fatriasari et al 2020). In another report, acetic lignin was reacted with PEDGE under atmospheric pressure, which reduced the amphiphilic viscosity to less than 0.3 dl/g and was effectively used as a cellulose stabilizer (Uraki et al, 2001).…”