Biogas is one of the alternative energy sources that can be updated and can reduce national energy dependence on fossil energy. Biogas has the main composition namely Methane (CH4), Carbon Dioxide (CO2) and Hydrogen Sulphide (H2S). The CO2 content in biogas is still quite large. This causes the efficiency of heat produced is still low so the quality of biogas is still not optimal. Therefore, it is necessary to absorb CO2 content using an absorber. In the Absorption process using clamshell packing as filling material in the absorber column which serves to expand the sensitivity of biogas with absorbent (NaOH). In this study, the variables studied were the effect of flow rate and NaOH concentration on CO2 reduction in biogas so that the purpose of this study was to obtain the optimum conditions from the effect of flow rate and NaOH concentration on CO2 levels. The results of the analysis and calculations obtained showed that the optimum conditions of the absorption process occurred at the flow rate of 9 liters/min and 2 M NaOH with CO2 absorption of 8.1972 grams. In this study, the variation of the flow rate used was 6,7,8,9 and 10 liters/min and variations in the concentrations of 0.5 M NaOH, 0.1 M, 1.5 M, 2 M and 2.5 M NaOH concentrations of 8.6526 grams of CO2 absorbed. From the laboratory analysis, the rate of CH4 and CO2 in biogas was 58.5% by volume and 27.6% by volume while the content of CH4 and CO2 in biogas after absorption was 66.1% volume and 18.0% volume.

This study aims to separate glycerol from used cooking oil biodiesel products. This research is done by main process by analyzing free fatty acid level (FFA) to know the fat content of the oil to determine the next process. This research is done by electrolysis process using high voltage. We did transesterification process by using methanol and NaOH as catalyst before performing the process of electrolysis with high voltage. Biodiesel is manufactured using a mini-scale stirred tank reactor (RATB) laboratory. This process is heated at temperature (35-60)C, the ratio of used cooking oil and methanol (5:1, 6:1, 7:1, 8:1, 9:1) using a 0.1 N NaOH catalyst. The research obtained optimum reaction temperature yield highest percentage of yield at temperature 60C and ratio of used cooking oil and methanol 5:1 with percentage of yield equal to 88.88, cetane number 48.4, kinematic viscosity 2.560, pour point 37.4F, flash point 131F, Conradson Carbon Residue (CCR) 0.09, and ASTM Color 1.5. This shows that the manufacture of biodiesel with high microwave and high voltage utilization yields a high percentage of 88.88 and the product is biosolar-48.

This research conducted to convert plastic bags into liquid fuels to be used as alternative fuels in generators to produce electricity. The purpose was to get the influence of the electrical load (200;400; 600;800; and 1000 watt) and ratio liquid fuel product with gasoline (0:5;1:4;2:3;3:2;4:1;and 5:0) towards performance liquid fuel the result of conversion Polypropylene (PP) and Low-Density Polyethylene (LDPE) plastic waste on the unit prototype plastic waste power plant with design capacity 1 KWH in terms of Specific Fuel Consumption (SFC) value, Torque and effective power generator. Effective power and torque analyzed using tachometer, voltmeter, ampere meter, and stopwatch while SFC calculation of liquid fuel consumption. Analysis of this data using descriptive statistical analysis that is describing collected data after being given treatment during the research, by presenting data in the form of tables, figures, and calculations. The results of the research show that the ratio liquid fuel:gasoline 2:3 with 800 Watt Electrical load produced of engine power, torque, and SFC optimal with results 1.280 Hp, 173.611 Nm, and 0.461 Kg/Hp.hr., with type of Polypropylene plastic, while type of Low Density Polyethylene plastic have the result 1.259 Hp, 170.753 Nm, and 0.536 Kg/Hp.hr., so that by mixing it can save conventional fuel specially gasoline.

This community service activity for processing used cooking oil into biodiesel was carried out at Banyuasin III SMPN 5, South Sumatra. Around the school there are many fried traders and tent stalls that have the potential to produce used cooking oil. Seeing this potential, the community service team of the Sriwijaya Polytechnic Department of Chemical Engineering provided training to students and teachers of the South Sumatra Banyuasin SMPN 5 to make laboratory-scale biodiesel from used cooking oil. Biodiesel production can be used to increase the potential of human resources and preserve the environment from used cooking oil pollutants. The method of implementing this service activity is with the pattern of field schools with press points on the exploration of knowledge, awareness of the environment, and skills and forms of approach taken to increase the motivation of students and teachers as partners and able to process used cooking oil into biodiesel by socializing about the importance of saving fossil fuels, protecting the environment and producing alternative fuels from used cooking oil which are often found in everyday life.

Biopelet adalah salah satu sumber energi alternatif untuk mengurangi ketergantungan bahan bakar fosil. Penelitian ini bertujuan untuk mendapatkan suhu optimal dan rasio ideal biopellet yang terbuat dari cangkang dan inti biji karet dalam produksi biopellet menggunakan mesin pengepres minyak ulir sesuai Standar Nasional Indonesia (SNI 8021-2014) yang meliputi nilai pemanasan, kadar abu, kadar air, bahan mudah menguap, dan kepadatan biopellet. Jumlah sampel biopellet dalam penelitian ini adalah 10 sampel dengan berbagai variasi suhu bahan dasar. Perbandingan cangkang dan inti biji karet dalam penelitian ini meliputi: 80:20, 70:30, 60:40, 50:50, dan 40:60 dengan variasi suhu 200ᵒC dan 150ᵒC. Hasil penelitian diketahui bahwa komposisi biopelet terbaik adalah sampel pada suhu 200ᵒC, dan rasio cangkang dan kernel biji karet 80:20 dengan nilai kalor 5,083,4919 kal/g, kadar air 4,00%, kepadatan 1,6322 g/cm3, kadar abu 1,9802%, bahan mudah menguap 77,1888%, dan karbon tetap 16,8317%. Nilai kalor dan analisis terdekat telah memenuhi SNI 8021: 2014.