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Optimization of Xylose Production from Sugarcane Trash by Microwave-Maleic Acid Hydrolysis Hermiati, Euis; Oktaviani, Maulida; Ermawar, Riksfardini Annisa; Laksana, Raden Permana Budi; Kholida, Lutfi Nia; Thontowi, Ahmad; Mardiana, Siti; Watanabe, Takashi
Reaktor Volume 20 No.2 June 2020
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (528.661 KB) | DOI: 10.14710/reaktor.20.2.81-88

Abstract

Sugarcane trash contains significant amount of xylan that could be hydrolysed to xylose. The xylose could be further fermented to produce xylitol, a sugar alcohol that has low calories and does not cause carries of teeth. In this study we optimized the production of xylose from sugarcane trash by microwave-assisted maleic acid hydrolysis using response surface methodology (RSM). The factors optimized were acid concentration, time, and temperature. The xylose yield based on the weight of initial biomass was determined and it served as a response variable. Results show that acid concentration and interaction between time and temperature had significant effect on xylose yield. The quadratic regression model generated from the optimization was fit and can be used to predict the xylose yield after hydrolysis with various combinations of acid concentration, time, and temperature. The optimum condition for xylose production from sugarcane trash was using maleic acid of 1.52%, and heating at 176 °C for 6.8 min. At this condition the yield of xylose was 24.3% per initial biomass or 0.243 g/ g biomass.Keywords: maleic acid; microwave heating; response surface methodology; sugarcane trash, xylose
Optimizing the Synthesis of Lignin Derivatives from Acacia mangium to Improve the Enzymatic Hydrolysis of Kraft Pulp Sorghum Bagasse Fatriasari, Widya; Hamzah, Fajar Nur; Pratomo, Bagas Ikhasan; Fajriutami, Triyani; Ermawar, Riksfardini Annisa; Falah, Faizatul; Laksana, Raden Permana Budi; Ghozali, Muhammad; Iswanto, Apri Heri; Hermiati, Euis; Winarni, Ina
International Journal of Renewable Energy Development Vol 9, No 2 (2020): July 2020
Publisher : Center of Biomass & Renewable Energy, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/ijred.9.2.227-235

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. 
Pretreatment of Oil Palm Empty Fruit Bunch (OPEFB) at Bench-Scale High Temperature-Pressure Steam Reactor for Enhancement of Enzymatic Saccharification Sari, Fahriya Puspita; Falah, Faizatul; Anita, Sita Heris; Ramadhan, Kharisma Panji; Laksana, Raden Permana Budi; Fatriasari, Widya; Hermiati, Euis
International Journal of Renewable Energy Development Vol 10, No 2 (2021): May 2021
Publisher : Center of Biomass & Renewable Energy, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/ijred.2021.32343

Abstract

Upscaling of biomass pretreatment from laboratory scale to a bench-scale reactor is one of the important steps in the application of the pretreatment for pilot or commercial scale. This study reports the optimization of pretreatment conditions, namely reaction temperature and time, by one factor at a time (OFAT) method for the enhancement of enzymatic saccharification of oil palm empty fruit bunch (OPEFB). OPEFB was pretreated using high temperature-pressure steam reactor with different reaction temperatures (160, 170, 180, 190, 200 °C) and times (10, 20, 30, 40, 50 min). The effectiveness of the pretreatment was determined based on chemical compositions of raw OPEFB and OPEFB pulp and sugar production from enzymatic saccharification of the OPEFB pulp.  Solubilized components from OPEFB, such as glucose, xylose, formic acid, acetic acid, 5-hydroxymethyl furfural (HMF), and furfural in the hydrolysate that generated during steam pretreatment were also determined. Pretreatment at 180°C for 20 min provides the highest sugar yields (97.30% of glucose yield per initial cellulose and 88.86% of xylose yield per initial hemicellulose). At the optimum condition, 34.9% of lignin and 30.75% of hemicellulose are successfully removed from the OPEFB and resulted in 3.43 delignification selectivity. The relationship between severity factor and by-products generated and the sugars obtained after enzymatic saccharification are discussed. The pulp of OPEFB at the optimum condition was also characterized for its morphological characteristic by scanning electron microscopy (SEM) and crystallinity by X-ray diffractometry (XRD).  These pulp characteristics are then compared with those of the raw OPEFB. The steam pretreatment causes some fiber disruptions with more defined and opened structures and increases the crystallinity index (CrI) by 2.9% compared to the raw OPEFB.
Bio-Polyurethane Resins Derived from Liquid Fractions of Lignin for the Modification of Ramie Fibers Aristri, Manggar Arum; Lubis, Muhammad Adly Rahandi; Laksana, Raden Permana Budi; Falah, Faizatul; Fatriasari, Widya; Ismayati, Maya; Wulandari, Asri Peni; Nurindah
Jurnal Sylva Lestari Vol. 9 No. 2 (2021): May
Publisher : Department of Forestry, Faculty of Agriculture, University of Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jsl29223-238

Abstract

Lignin is a biopolymer from agro-forestry biomass which provides greater prospects for higher added value applications in renewable and sustainable products. In this study, technical lignin from black liquor was used as a pre-polymer for the preparation of bio-polyurethane (Bio-PU) resins. Briefly, the isolated lignin was fractionated using ethyl acetate (EtAc) and methanol (MeOH). The liquid fractions of lignin, such as lignin-EtAc (L-EtAc) and lignin-methanol (L-MeOH), were mixed with 10% of polymeric isocyanate (based on the weigth of liquid fractions) to obtain Bio-PU resins. The isolated lignin, fractionated lignin, and lignin-derived Bio-PU resins were characterized using several techniques. The obtained Bio-PU resins then were used to modify ramie fibers using vacuum impregnation method. Fourier Transform Infrared (FTIR) spectroscopy, Differential Scanning Calorimetry (DSC), and Thermogravimetric Analysis (TGA) revealed that the isolated lignin had quite similar characteristics to lignin standar. Fractionation of lignin with EtAc and MeOH altered its characteristics. FTIR, DSC, and TGA showed that solid fractions of lignin had similar characteristics to lignin standard and isolated lignin, while the liquid fractions had characteristics from lignin and the solvents. The absorption band of isocyanate (-N=C=O) groups was shifted to 2285 cm-1 from 2240 cm-1 owing to the reaction with the -OH groups in lignin, forming urethane (R-NH-C=O-R) groups at 1605 cm-1 in Bio-PU resins. Thermal properties of Bio-PU resins derived from L-EtAc exhibited greater endothermic reaction compared to Bio-PU-L-MeOH. As a result, the free -N=C=O groups in Bio-PU resins have reacted with -OH groups on the surface of ramie fibers and improved its thermal properties. Modification of ramie fibers with Bio-PU resins improved the fibers' thermal stability by 15% using Bio-PU-LEtAc for 60 min of impregnation. Keywords: bio-polyurethane resins, impregnation, lignin fractions, ramie fibers, thermal stability