Separation and Purification Residual Salt from Glycerine Pitch from Waste of Refined Glycerine Production

¹ Department of Chemical Engineering, Institut Teknologi Sepuluh Nopember, 60111 Surabaya, Indonesia
² Department of Chemical Engineering, Institut Teknologi Kalimantan, 76127 Balikpapan, Indonesia

^* Corresponding author: gunawan@chem-eng.its.ac.id

Abstract

The glycerol refining process produces 5%wt/ton waste in the form of glycerine pitch (GP) and has the potential to pollute the environment if not properly handled and expensive handling costs. In this study, GP was characterized by its chemical composition and spectroscopic analysis using FTIR and UV-Vis. The sodium chloride content of 15-30% contained in GP was separated and purified by solid-liquid extraction. Solvent selection (methanol, ethanol and acetone), solvent ratio (1:3, 1:5 and 1:10) and extraction time (10, 15 and 30 min) were evaluated using one factor at the time (OFAT) method. The methanol was found to be the optimum solvent and the best ratio at 1:5 produced sodium chloride purity around 81%. However, the effect of extraction time was declared not significant with a pvalue above 0.05. The TOC result of residual salt was 44 ppm and residual methanol content was not detected after heating. The integrated process of separation and purification of residual salt from GP is easy to apply and zerowaste potential in organic waste after extraction can be achieve by combustion in boiler with a calorific value obtained of 3000-3200 cal/g.