The main purpose of this study is to produce and generate a solid acid catalyst from biomass with high reactivity that can be used in catalytical reactions such as hydrolysis, and is environmentally friendly and reusable. A biocarbon-based sulfonated catalyst was prepared by the carbonization of palm empty fruit bunches (PEFB), followed by sulfonation. In order to enhance the acidity of the biocarbon, different concentrations of hydroxyethylsulfonic acid were added to the solution during sulfonation at 180 o C for 4 h in a Teflon stainless steel autoclave. The H + ion capacity of the biocarbon-sulfonated acid catalyst (BSC) was increased twofold (3.57 mmol/g) in the presence of 10% of hydroxyethylsulfonic acid and 10% of acrylic acid. X-Ray Fluorescence (XRF) analysis showed that the BC-SO3H contained 38% of S. The original structure of the PEFB after carbonization disintegrated from the fibrous materials onto porous carbon. The crystalline index (CrI) of the PEFB significantly decreased to about 32% and a wide broad peak of a X-Ray Diffraction (XRD) pattern of around 2030 o were observed, which shows that an amorphous biocarbon structure had been identified. Fourier Transform Infra-Red (FT-IR) analysis confirmed that the-SO3H, COOH and-OH functional groups were deposited on the carbon due to specific peaks at around 1180 cm-1 , 1724 cm-1 and 3431 cm-1 , respectively. Decomposition of the sulfonic groups on the biocarbon-sulfonated solid catalyst was observed from 227.9 o C, as it shown by thermal gravimetric analysis (TGA).

Abstrak- Kulit jeruk pakis (Citrus grandis) merupakan limbah yang dihasilkan dari kegiatan rumah tangga, industri dan pertanian. Dengan proses distilasi kulit jeruk pakis dapat diambil minyaknya sebagai citrus oil yang selanjutnya dapat dimanfaatkan sebagai bahan baku pembuatan sabun. Penelitian ini bertujuan untuk membandingkan rendemen dan mutu citrus oil dari bahan baku kulit jeruk pakis segar dan dikeringkan (40 oC, 6 jam) dengan metode water distillation. Massa kulit jeruk yang digunakan adalah 200, 300, 400 dan 500 gram diekstraksi selama 3 jam pada 100 °C. Rendemen minyak yang diperoleh untuk kulit jeruk pakis segar berturut-turut pada massa kulit jeruk 200, 300, 400 dan 500 gram ialah  0,888 %, 0,619%, 0,178% dan 0,239% sedangkan untuk kulit jeruk yang keringkan diperoleh rendemen berturut-turut 0,214%, 0,029%,0,074% dan 0,023%. Minyak yang dihasilkan dari kulit jeruk segar dan kering dianalisa dengan Gas Chromatography Mass Spectrometry (GCMS) mengandung 82,136% limonen. Kulit jeruk pakis sebelum dan sesudah diekstraksi dianalisa dengan Scanning Electro Microscopy (SEM) dan X-Ray Diffraction (XRD) menunjukkan bahwa struktur permukaan setelah ekstrasi menjadi rusak dan struktur kristalinnya tidak mengalami perubahan yang signifikan. Minyak yang dihasilkan selanjutnya direaksikan dengan NaOH 30% untuk menghasilkan sabun. Kadar pH sabun pada konsentrasi (w/v) 1%, 5% dan 10% dalam 100mL air berturut-turut sebesar 9, 10 dan 10 sedangkan kadar air dalam sabun yang diperoleh sebesar 37,25%. Kata Kunci: jeruk pakis, minyak kulit jeruk, water distillation, sabun Abstract- Pakis orange peel is one of wasted product from household, industry and agriculture activities. Pakis orange peel can be extracted by distillation as citrus oil. Furthermore, it can be used as essential oil in production of soap. The purposes of this research  is to compare yield and quality of citrus oil base on fresh and dried  pakis orange peel (40°C, 6 hours) by water distillation methode. The variation mass of orange peel was used  200, 300, 400 and 500 gram then was extracted  for 3 hours at 100°C. The yield of citrus oil from fresh pakis orange peel with weight 200, 300, 400 and 500 gram are 0,888%, 0,619%, 0,178% and 0,239%,  respectively. The dried pakis orange peel was produced citrus oil 0,214%, 0,029%, 0,074% and 0,023%, respectively. The citrus oilwas analyzed by Gas Chromatoghrapy Mass Spectrometry (GCMS) which was contained ca. 82,13% of limonene. Pakis orange peel before and after extraction analyzed with Scanning Electro Microscopy (SEM) and X-Ray Diffraction (XRD) were indicated the structure of surface area after extraction has become broken  and the sructure of crystalline structure was not significant changes. Furthermore, citrus oil obtained from extraction was reacted with 30% NaOH for soap production. The pH of soap at concentration 1%, 5% and 10% (w/v) in water  9, 10 and 10, respectively.  The water content in the soap about 37,25%. Keywords: pakis orange, orange peel oil, water distillation, soap