Liquefaction of Plastic for Fuel Production and Application of Volcanic Ash as Catalyst

Plastic is capable of being formed into various shapes for several applications. Therefore, demand for plastic has increased every year. The increase in the use of plastic correspondingly increases the amount of waste plastic being produced. Hydrocracking, pyrolysis, liquefaction under hydrogen gas pressure system, and catalytic conversion of waste plastic was studied by several researchers to produce liquid fuel. In this research, a method to convert polyethylene type of plastic into liquid fuel was developed. The polyethylene plastic was treated by liquefaction method without hydrogen gas pressure and without any solvents under mild conditions. The liquefaction process was carried out in an autoclave in a range of temperature from 200-350 degrees C and pressure of 1-10 kg/cm2. Liquefaction process at 200 degrees C was produced a solid product. Plastic liquefaction oil was recovered after liquefaction at 250 degrees C, however, the oil consisted of two layers that bottom layer was more concentrated than the upper layer. Homogenous yellow clear oil was recovered at 300 degrees C for more than 10 nun as well as at 350 degrees C for 0 - 60 mm During liquefaction from 250 - 350 degrees C, solid residue was negligible. In liquefaction of plastic, an activity of volcanic ash as a catalyst was investigated. Volcanic ash contained silica and aluminium oxide. Utilization of volcanic ash as a catalyst was able to crack the plastic into chemicals with low carbon chains (C8-C9) Plastic liquefaction oil mainly consisted of cyclic chemical compounds.