Pengaruh Steam Pretreatment terhadap Degradasi Selulosa dan Limonen pada Limbah Jeruk dalam Produksi Biohidrogen

Abstract

This research presents the influence of steam pretreatment to orange waste and its effect on the production of biohydrogen. The steam pretreatments with various times of 2, 4, and 6 hours were applied to the samples. After the pretreatment, the samples were fermented for seven days, and the contents of cellulose, limonene, volatile fatty acid (VFA), and hydrogen were assessed on the days of 1, 2, 3, 5 and 7. Kinetic parameters of hydrogen production were evaluated using the modified Gompertz`s equation. The result of this research showed that the steam pretreatment significantly reduced the cellulose and limonene compounds. The content of cellulose in the substrate after 2, 4 and 6 hours pretreatment were 37.08%; 36.63%; and 15.95%, respectively. Moreover, the content of limonene after pretreatment of 2, 4, and 6 hours were 57.44 ppm; 38.80 ppm; and 36.11 ppm, respectively. Analysis of kinetic parameters of production of hydrogen showed that the maximum productions of hydrogen (H_max) in the samples after pretreatment of 2, 4, and 6 hours were 11.492 mL; 52.612 mL; 22.345 mL, respectively. The maximum production rates (Rm) at specified pretreatment time (2, 4, and 6 hours) were 9.888 mL H₂/hour; 10.008 mL H₂/hour; 12.982 mL H₂/hour and the lag phases were 49.689 hours; 24.742 hours; and 24.885 hours. The study elucidated that applying pretreatment for 4 hours gives the optimum condition for hydrogen production.

 

A B S T R A K

Penelitian ini mempelajari pengaruh steam pretreatment terhadap limonen dan selulosa yang terkandung pada limbah jeruk, dengan mengevaluasi dampaknya terhadap produksi biohidrogen. Steam pretreatment dilakukan dalam 3 variasi waktu, yaitu 2, 4 dan 6 jam. Kemudian proses fermentasi dijalankan selama 7 hari dengan pengambilan sampel dilakukan pada hari ke 1, 2, 3, 5 dan 7. Hasil dari penelitian ini menunjukkan bahwa steam distillation yang dilakukan untuk pretreatment pada substrat jeruk berpengaruh terhadap kondisi substrat, yaitu mengurangi kadar selulosa dan limonen. Kadar selulosa pada substrat setelah pretreatment 2 jam adalah 37,08%; 4 jam 36,63%; dan 6 jam 15,95%. Sementara kadar limonen setelah pretreatment 2, 4 dan 6 jam berturut-turut 57,44 ppm; 38,80 ppm; dan 36,11 ppm. Konstanta kinetika produksi hidrogen pada sampel dengan pretreatment 2, 4 dan 6 jam yang diperoleh dengan persamaan Gompertz termodifikasi adalah potensi produksi hidrogen (H_maks) 11,492 mL; 52,612 mL; 22,345 mL, laju produksi maksimum (R_m) 9,888 mL H₂/jam; 10,008 mL H₂/jam; 12,982 mL H₂/jam serta waktu adaptasi 49,689; 24,742; dan 24,885 jam. Perlakuan pretreatment pada sampel selama 4 jam menghasilkan produk paling optimal.