This study aims to investigate the adsorption of methylene blue (MB) over particulate durian peel waste, which is chemically-activated with hydrogen peroxide. The equilibrium data is well-described by the Freundlich isotherm model, which outlines where the MB adsorption takes place predominantly on multilayers and heterogeneous surfaces of the biosorbent. The Freundlich adsorption constants, KF and n, are 11.06 L/g and 2.94, respectively. Thermodynamic data suggests that the MB adsorption occurs spontaneously and exothermically. The enthalpy and entropy for the MB adsorption are obtained as 10.26 kJ/mol and 0.058 kJ/mol K, respectively, in the temperature range of 303–323 K. Based on the stepwise desorption method, the adsorption of MB is dominated by physical interactions, particularly hydrogen bonding.

In this study, the optimization of microwave-assisted alkaline (MAA) pretreatment is performed to attain the optimal operating parameters for the delignification of cocoa pod husk (CPH). The MAA performance was examined by heating the CPH solid with different particle sizes (60–120 mesh) and NaOH solution with a different sample to a solvent (SS) ratio (0.02–0.05 g/L), for short irradiation time (1–4 min). Box-Behnken Design (BBD) was utilized to optimize the percentage of lignocellulose composition changes. The results show that by enlarging particle size, the content of lignin and cellulose decreased while hemicellulose increased. By prolong irradiation time, the content of lignin and hemicellulose decreased while cellulose elevated. On the other hand, increasing the SS ratio was not significant for hemicellulose content changes. From FTIR and SEM characterization, the MAA drove the removal of lignin and hemicellulose of CPH and increased cellulose slightly. Supported by kinetic study which conducted in this work, it was exhibited that MAA pretreatment technology is an effective delignification method of CPH which can tackle the bottleneck of its commercial biofuel production. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA   License (https://creativecommons.org/licenses/by-sa/4.0).

<p>Abstract: Pineapple skin is an agricultural waste that has a carbohydrate content of about<br />10:54% and the skin of pineapple juice glucose levels by 17% so it can be utilized to ethanol.<br />Hydrolysis reaction is so slow that the reaction requires a catalyst. The catalyst used in this<br />study were hydrochloric acid (HCl). This study aims to Learn how to use the skin of pineapple<br />waste as alternative raw material manufacture bioethanol. The variables studied were the<br />concentration of hydrochloric acid, the hydrolysis and fermentation time. Sorghum starch<br />hydrolysis process using a three neck flask equipment, mercury stirrer, heating mantle, cooling<br />behind and a thermometer to measure temperature. Sampling for glucose analysis performed<br />when the temperature reaches 100 ºC every 45 minutes to obtain optimum glucose levels.<br />Glucose samples were analyzed by using the Lane-Eynon. Data analysis showed the longer the<br />higher the hydrolysis of the resulting glucose levels, but there are times when the glucose level<br />will drop over time for glucose resulting damage due to continuous heating. In the fermentation<br />process is carried out with fermentation time of 24 hours, 48jam, 72 hours, 96 hours, 120 hours<br />fiber. The most optimum bacterial activity is a long fermentation for 96 hours. Distillation process<br />carried out on the final results of ethanol fermentation and obtained the highest levels of<br />31.399%.<br />keyword : Pineapple skin, hydrolysis, fermentation, distillation, ethanol.</p>

<p><strong><em>Abstract: </em></strong><em>Pineapple skin is an agricultural waste that has a carbohydrate content of about 10:54% and the skin of pineapple juice glucose levels by 17% so it can be utilized to ethanol. Hydrolysis reaction is so slow that the reaction requires a catalyst. The catalyst used in this study were hydrochloric acid (HCl). This study aims to Learn how to use the skin of pineapple waste as alternative raw material manufacture bioethanol. The variables studied were the concentration of hydrochloric acid, the hydrolysis and fermentation time. Sorghum starch hydrolysis process using a three neck flask equipment, mercury stirrer, heating mantle, cooling behind and a thermometer to measure temperature. Sampling for glucose analysis performed when the temperature reaches 100^oC every 45 minutes to obtain optimum glucose levels. Glucose samples were analyzed by using the Lane-Eynon. Data analysis showed the longer the higher the hydrolysis of the resulting glucose levels, but there are times when the glucose level will drop over time for glucose resulting damage due to continuous heating. In the fermentation process is carried out with fermentation time of 24 hours, 48 hours, 72 hours, 96 hours, 120 hours fiber. The most optimum bacterial activity is a long fermentation for 96 hours. Distillation process carried out on the final results of ethanol fermentation and obtained the highest levels of 31.399%.</em></p><p><strong><em> </em></strong><strong><em>Keywords</em></strong><em> : Pineapple skin, hydrolysis, fermentation, distillation, ethanol.</em></p><p> </p>

Rice is a carbohydrate source and staple food for around the world of people, specially in Asia. Carbohydrate consumption , especially rice, can have effects of diabetes desease type 2. It is caused by the glycemic index of white rice is higher of 56. This research was conducted to study the effects of parboiled ciherang rice and extract of keji beling leaf. The rice was submerged for 6 hours so the mouisture increased to 30%. It was cooked in an autoclave at 116 ^oC for 15 minutes. The cooked rice then it was dried at 50 oC for 24 hours. This method didn’t have effects on reducing glycemic index but it increased the glycemic index higher than 54, e.g. 56 by tester 1 and 80 by tester 2.