Pemurnian Bioetanol Menggunakan Adsorben Silika Gel dari Limbah Botol Kaca di Industri Kecap

Waste glass bottles is an inorganic waste that amounts to 0.7 million tons per year with the main content of silica, so it can be used as the main ingredient to produce silica gel. In the soy sauce industry, waste glass bottles came from depalletizer activities, the activity of moving glass bottles to the cleaning area. This research aims to utilize waste glass bottles as a raw material for producing silica gel adsorbents using the hydrothermal method and the sol-gel approach. Silica gel becomes an adsorbent in the purification of bioethanol from wastewater washing dissolving tanks using the adsorption method. Variations in the bioethanol production are yeast weight as 0, 2, 5, and 8 g as well as fermentation time for 4, 7, and 10 days.The bioethanol purification process used variations in adsorption time for 40, 60, and 80 minutes. Characterization of silica gel using BET and SEM-EDX test. The BET test results show that activated silica gel has a surface area of ​​231,851 m2/g. Analysis by SEM-EDX showed that the Si and O elements in activated silica gel were 40,94% and 51,92%. Based on the results of the GC-MS test, 60 minutes is the best adsorption time to increase the bioethanol content from 39,8±9,9% to 72,0±1,1%.