Recycling industrial ethanol waste to solid alcohol and improvement of its physical, chemical and fuel properties

Abstract

Importance of the work: Ethanol waste from the herbal industry has potential as a raw material for recycling to solid alcohol production.
Objectives: To appraise the physical, chemical and fuel properties of solid alcohol using a water boiling test and heating values.
Materials & Methods: Testing involved solid alcohol produced from curing agents of cellulose, hydroxyethyl cellulose and hydroxypropyl methylcellulose (HPMC) with and without charcoals—bamboo charcoal (BC), cassava rhizome charcoal (CC) or activated carbon from cassava rhizome (AcC)—during 6 mth of storage.
Results: The analysis of the charcoals and activated carbon showed that BC had better chemical properties than CC and AcC, respectively, due to its lower moisture content, volatile matter and ash content; however, it had higher fixed carbon. The solid alcohol produced from HPMCBC had the best fuel properties based on the solid alcohol weight (21.7 g) and the highest total burning time (617–775 s) compared to the control without any curing agents or additives (18.4 g and 539–624 s, respectively). Adding AcC into the solid alcohol decreased its weight, increased the ash residue content, caused shrinkage and was unable to pass the boiling water test. Thus, mixing charcoal (but not activated carbon) into the solid fuel might be an option to study further.
Main finding: The control solid alcohol had calorific values in the range 4,750–4,990 kcal/kg that were considered adequate. This research proposed using HPMCBC and improving the chemical reaction and fuel properties for solid alcohol production and usage.