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.

The number of means of transportation in Indonesia continues to increase from year to year. Along with this, the amount of used oil waste oil becomes something more useful by considering the high hydrocarbon content, namely the pyrolysis method with a raw material ratio of 1:1 to be converted into liquid fuel which is ready to be commercialized by catalytic cracking process using a zeolite catalyst of a certain amount. 25% by weight of the raw material which is useful for accelerating the reaction so as to save energy use and improve the quality of the resulting product. Observations were made by looking at the effect of temperature variations ranging from 250oC, 300oC, 350oC, to the results of the pyrolysis process which aims to obtain the optimal process temperature.

In this research, a pyrolysis reactor with a capacity of 5 kg has been designed. Innovation in the pyrolysis reactor is the adsorbents that are used (lime CaCO3 + iron fiber Fe2O3) in the reactor. This study aims to determine the optimal reaction conditions. Tests carried out at 200-400°C temperature intervals and a range of 40-90 minutes. The best product is 86.40% liquid yield at 350°C with a processing time of 90 minutes. ASTM distillation studies of the oil produced showed that 67% fraction was in the range of the light naphtha, 12% fraction was in the range of heavy naphtha and 21% fraction was in the range of the medium naphtha. Comparing the physical parameters of the sample oil with standard fuels, it was observed that the fractions collected were in the range of gasoline, kerosene and diesel oil. This research contributes significantly to increasing knowledge about the feasibility of pyrolysis, providing opportunities for the recycling sector to spread take-off systems, in the Circular Economy.

This study aims to examine catalytic pyrolysis with activated natural zeolites. A pyrolysis reactor with three levels of separator as a result of development was used to study the catalytic pyrolysis of plastic waste into liquid fuel at intervals of 200 -400 oC and operating time of 30-90 minutes. As the object, a mixture of plastic bottles of highdensity polyethylene (HDPE) and polystyrene (Styrofoam) was used, sized 5-10 mm2 The results showed that the application of 3 levels of separator and Zeolite ZAA as a catalyst in the catalytic conversion of a mixture of polyethylene and polystyrene (Styrofoam) had the effect of shortening the reaction time and increasing the production of oil yield. Physiochemical studies of all fractions showed that the fractions concerned had gasoline properties, kerosene or diesel. The composition of the fractions produced by the top, medium and bottom separator showed an increase in the percentage of heavier hydrocarbons that tended to go to the bottom separator. At the optimal reaction temperature conditions of 350 oC for 90 minutes, a range of gasoline (C5-C10) hydrocarbons was produced at 55.17% in the top separator with a total conversion of 97.20%. This study contributes significantly to increasing knowledge about the feasibility of catalytic pyrolysis for the conversion of plastic waste into liquid fuel for people who do plastic waste processing industries in potential areas.

No abstract