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All Journal Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains Journal of Bioprocess Chemical and Environmental Engineering Science
Darmiyati, Siti
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Chemical Engineering, Chemistry & Bioengineering Control & Systems Engineering Decision Sciences, Operations Research & Management Engineering Environmental Science Industrial & Manufacturing Engineering Materials Science & Nanotechnology

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Isolasi Kitin Dari Limbah Cangkang Kepiting Bakau (Scylla Olivacea) Dengan Variasi Konsentrasi Natrium Hidroksida Dan Suhu Pada Proses Pembuatan Serbuk Kitin Darmiyati, Siti; Drastinawati, Drastinawati; Yusnimar, Yusnimar
Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains Vol 5, No 1 (2018): Wisuda April Tahun 2018
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains

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Abstract

Chitin is poly (2-acetamido-2-deoxy-β(1,4)-D-glucopyranose). Chitin can be isolated through several stages of chitin powder production, demineralization stage and bleaching stage. The purpose of this study is to learn the effect of concentration of sodium hydroxide and temperature in the process of chitin powder production, analyze chitin by using FTIR (Fourier Transform Infrared) spectrophotometer and determining moisture content, ash content and yield. The research procedure begins with crab shell waste size reduction into a powder size. The process of chitin powder production was carried out using concentration of NaOH variations (2.5%, 3.5% and 4.5%) and temperature (550C, 650C dan 750C), the ratio of 1:10 (w/v) for 2 hours and stirring speed 150 rpm, then demineralization process using HCl 1.5 N, the ratio of 1:15 (w/v) for 1 hour and stirring speed 150 rpm, then bleaching process using 4% NaOCl, the ratio of 1:15 (w/v) for 1 hour. The results showed that the higher concentration of NaOH and temperature, the yield, the water content and the resulting ash content were lower at 4.5% NaOH concentration and 750C at 15.54%, 4.13% and 0.5%. Based on the results of the obtained FTIR showed that the residue from isolation was chitin.Keywords: bleaching, crab shells, demineralization, FTIR, chitin.
Isolasi Kitin Dari Limbah Cangkang Kepiting Bakau (Scylla Olivacea) Dengan Variasi Konsentrasi Natrium Hidroksida Dan Suhu Pada Proses Pembuatan Serbuk Kitin Darmiyati, Siti; Drastinawati, Drastinawati; Yusnimar, Yusnimar
Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains Vol 5, No 1 (2018): Wisuda April Tahun 2018
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Chitin is poly (2-acetamido-2-deoxy-β(1,4)-D-glucopyranose). Chitin can be isolated through several stages of chitin powder production, demineralization stage and bleaching stage. The purpose of this study is to learn the effect of concentration of sodium hydroxide and temperature in the process of chitin powder production, analyze chitin by using FTIR (Fourier Transform Infrared) spectrophotometer and determining moisture content, ash content and yield. The research procedure begins with crab shell waste size reduction into a powder size. The process of chitin powder production was carried out using concentration of NaOH variations (2.5%, 3.5% and 4.5%) and temperature (550C, 650C dan 750C), the ratio of 1:10 (w/v) for 2 hours and stirring speed 150 rpm, then demineralization process using HCl 1.5 N, the ratio of 1:15 (w/v) for 1 hour and stirring speed 150 rpm, then bleaching process using 4% NaOCl, the ratio of 1:15 (w/v) for 1 hour. The results showed that the higher concentration of NaOH and temperature, the yield, the water content and the resulting ash content were lower at 4.5% NaOH concentration and 750C at 15.54%, 4.13% and 0.5%. Based on the results of the obtained FTIR showed that the residue from isolation was chitin.Keywords: bleaching, crab shells, demineralization, FTIR, chitin.
Optimasi Proses pirolisis dari Kulit Kayu Akasia Crassicarpa Menjadi Bio-Char menggunakan Metode Respon Surface Methodologi Central Composite Design Darmiyati, Siti; Bahri, Syaiful; Sunarno, Sunarno
Journal of Bioprocess, Chemical and Environmental Engineering Science Vol 6 No 2 (2025): Journal of Bioprocess, Chemical, and Environmental Engineering
Publisher : Department of Chemical Engineering, Faculty of Engineering, UNRI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31258/jbchees.6.2.122-131

Abstract

The problem of fossil energy crisis and the increasing carbon emissions have encouraged the search for environmentally friendly alternative energy sources, one of which is through the utilization of biomass into solid fuels such as bio-char. This study aims to optimize the pyrolysis process conditions to produce high-quality bio-char from Acacia crassicarpa bark, a lignocellulosic waste from the forestry industry. The pyrolysis process was carried out in a batch reactor with variations in temperature (400–500°C), residence time (30–60 minutes), and NiMo/NZA catalyst concentration (2–6%) as independent variables. Optimization was carried out using the Response Surface Methodology approach with a Central Composite Design experimental design to obtain the optimum conditions. The results showed that the optimum conditions were obtained at a pyrolysis temperature of 400°C, residence time of 30 minutes, and catalyst concentration of 2%, resulting in a bio-char yield of 33.8% with a desirability value of 0.876. Meanwhile, the highest calorific value of 28 MJ/kg was achieved at the same temperature with a residence time of 90 minutes. This value exceeds the minimum standard for solid fuels according to the International Biochar Initiative and the European Biochar Certificate, which are generally in the range of >20–25 MJ/kg. Thus, the resulting bio-char not only has potential as an alternative energy source but also meets quality standards as an efficient and sustainable solid fuel.
Co-Authors Drastinawati Drastinawati, Drastinawati Sunarno Sunarno SYAIFUL BAHRI Yusnimar Sahan