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Co-pyrolysis and hydrogenation of Thar coal, waste plastic and waste oil blends for fuel oil production

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Co-liquefaction of Thar coal with waste plastic and waste oil was carried out to get high-quality fuel from waste. Four major variables, temperature, residence time, hydrogen pressure and coal: waste plastic ratio, oil: coal and oil: waste plastic ratios were investigated. According to results, maximum oil yield was obtained at 400°C temperature, 100psi pressure, 60 min residence time, and oil: coal: waste plastic ratios of 6:2:2. An FTIR result and 13 C NMR analysis have shown extracted oil contains almost 84% aliphatic compounds and 16% aromatic compounds. Among aliphatic, there is more %age of diesel fraction. Extracted residue can also be used as a fuel in cement industry and in power generation plants because it contains almost 83-84% carbon with less than 1% sulfur.
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... Combining waste plastics with low-rank coal for pyrolysis shows promise in inhibiting CO 2 emissions, increasing the yields of liquids and enhancing overall coal conversion efficiency. Researchers have determined that there are synergistic interactions when pyrolyzing plastics together with low-rank coal [17][18][19]. Qian et al. [20] observed significant influence from the active intermediates generated during waste plastic pyrolysis on its interactions with coal, resulting in enhancements in both the quality and yield of the resulting tar. Zhang et al. [21] demonstrated that the co-pyrolyzing coal with PE effectively decreases the heavy fraction in tar. ...
... Their analysis using the 13 C NMR technique revealed the presence of 84% aliphatic and 16% aromatic compounds. 75 Furthermore, a comparison of the main products obtained between the current and previous studies was conducted, and the details are listed in Table 8. The previous studies used different catalysts to enhance the production of gaseous and liquid products to obtain useful jet-fuels and petroleum-like hydrocarbons with a HZSM catalyst. ...
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