Maktum Muharja
Department of Chemical Engineering, University of Jember, Indonesia 68121

Nur Fadhilah
Department of Engineering Physics, Sepuluh Nopember Institute of Technology, Indonesia 60111

Rizki Fitria Darmayanti
Department of Chemical Engineering, University of Jember, Indonesia 68121

Dwina Moentamaria
Department of Chemical Engineering, State Polytechnic of Malang, Indonesia 65141

Arief Widjaja
Department of Chemical Engineering, Sepuluh Nopember Institute of Technology, Indonesia 60111

DOI: https://doi.org/10.19184/jobc.v1i1.110       

ABSTRACT
The objective of this study is to optimize the three significant parameters of the subcritical water (SCW) process for sugar production from coconut husk by using response surface methodology (RSM). In this study, the effect of temperature, reaction time and solvent-feed (S/F) ratio was evaluated and discussed comprehensively. The results showed that the S/F ratio had the most significant effect on sugar yield. The optimal sugar yield was obtained at the highest S/F ratio of 23.4, the shortest time of 4.8 min, and the highest temperature of 183.6 oC of the SCW process. The characterization results confirmed that the lignocellulose structure was changed remarkably then contribute to the efficient processes of enzymatic hydrolysis. The parameters evaluation using RSM in this study suggests that SCW hydrolysis could be subjected to commercial purposes.

Keywords: response surface methodology, subcritical water, enzymatic hydrolysis, sugar production, coconut husk

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