KONVERSI INULIN UMBI DAHLIA (Dahlia variabilis) MENJADI ASAM LEVULINAT DENGAN KATALIS ASAM SULFAT

Abstract

The dahlia tuber is not maximally use as biomass. Dahlia tuber contains 14% of inulin which potential as starting material to produce chemical platform like levulinic acid. Dahlia tuber used in this research originated from Bukitinggi Sumatera Barat Indonesia. Inulin was extracted from 100 g dahlia tuber by heating and precipitation using ethanol, produced grey coloured of 4 g inulin powder. Production of levulinic acid was done by hydrolyzing inulin at high temperature using sulfuric acid as catalyst and variation of reaction condition such as temperature, time and sulfuric acid concentration. Result of analysing using HPLC system showed that the main factors affecting the yield of levulinic acid were temperature and sulfuric acid concentration. Levulinic acid obtained by hydrolyzing inulin (5% substate concentration) in 0.1 M sulfuric acid at 170°C for 15 minutes was 14.785% (w/w inulin), by using 1 M sufuric acid at 1500C for 15 minutes was 15.6636% (w/w inulin), and by using 0.1 M sulfuric acid at 1500C for 40 minutes was 8% (w/w inulin).

Keywords : Dahlia tuber, inulin, levulinic acid