Pretreatment of Tobacco Stems as Bioethanol Raw Material: The Effect of Temperature and Time Using Chemical Method

Abstract

One type of alternative energy currently developed in Indonesia is bioethanol. The use of bioethanol as a fuel has several advantages compared to oil fuels such as cleaner burning and environmentally friendly because carbon monoxide gas emissions are lower, so it does not contribute to the accumulation of carbon dioxide in the atmosphere. Bioethanol can be made from biomass raw materials which contain sugar, starch, or cellulose. One of the abundant biomass in Indonesia is tobacco. Jember Regency has 6,078 ha of tobacco plantations. With an estimated number per hectare of 22,000 trees with an estimated stem weight of 0.5 kg, so 66,858 tons of tobacco stem waste will be available in Jember Regency. The availability of abundant tobacco stems is very potential to be used as raw material for making bioethanol. One of the important steps of bioethanol processes is pretreatment. This process aims to separate cellulose, hemicellulose, and lignin. Cellulose produced from the pretreatment process will be hydrolysis in the next stage. The amount of cellulose that can be separated from lignin and hemicellulose will affect the results in bioethanol production. The purpose of this research is to know the effect of temperature and time on the pretreatment process. The pretreatment method used is a chemical method because it has several advantages such as the cost is cheap, the material is easy to get, time is fast, and does not require high energy compared to other methods. The solvents used are H2SO4 and HCl. Analysis of lignin, cellulose, and hemicellulose using the Chesson method. Temperature variations in this research were 100 C, and 140 o C, 120 o o C with time 60 minutes obtained the cellulose 23.52%. For HCl solvents, the optimum temperature is 120 C. For H2SO4 solvents, the optimum temperature is 100 o C with time 60 minutes obtained the cellulose 24.43%.