Broido plot for the effect of acid pretreatments on hydrolysis of oil palm mesocarp fiber

Hydrolysis is one of the method used to produce levulinic acid. Before hydrolysis, the samples need to be pretreated to enhance the production of levulinic acid during hydrolysis reaction. Two different pretreatments, acid pretreatment and ultrasonic-assisted acid pretreatment were done followed by acid hydrolysis on oil palm mesocarp fibre (OPMF). For acid pretreatment, the parameter involved was temperatures (60 ⁰C, 80 ⁰C and 100 ⁰C) while the effect of sonication powers (40%, 60% and 80%) was investigated for ultrasonic-assisted acid pretreatment. Acid hydrolysis reaction was performed at the temperature of 140 ⁰C for 3 hours. The samples from hydrolysis were then prepared for thermo gravimetric analysis (TGA) and analysis by high performance liquid chromatograph (HPLC). TGA analysis revealed that the pretreated sample which produced the highest amount of levulinic acid based on HPLC result gave the lowest activation energy based on TGA result. This sample produced 11.45% levulinic acid and the activation energy for decomposition of this sample was only 15.16 kJ/mol. This indicates that the lowest energy was needed for decomposition of this treated sample due to the efficiency of acid pretreatment with its excellent condition towards fiber.