Kinetic study on the pyrolysis of low-density polyethylene (LDPE) waste using kaolin as catalyst

Abstract

The increase in the industrial and urban activities has resulted in the rise of plastic production and consumption. The higher demand for plastic causes accumulation of plastic waste in which it contributes to environmental problems. About 65-70% of plastic waste is a type of Low-Density Polyethylene (LDPE). To reduce this type of waste, the pyrolysis method can be an alternative. This study investigated the catalyst ratio and particle size of the material. The results indicate that the optimum catalyst was at 15% wt/wt with liquid and gas yields of 99.15% and 0.85%, respectively. Meanwhile, the optimum particle size variation is at 7.5 x 6.5 cm with liquid and gas yields of 99.82% and gas 0.18%, respectively. The proximate analysis of LDPE wastes includes the analysis of ash content, volatile matter, and fixed carbon, with the values of 0.35, 99.61 and 0.04% wt/wt, respectively. The chemical composition is analyzed using Shimadzu GCMS-QP2010S. The highest percentage component is heptane. The fuel analysis shows pyrolysis oil products comply with the national standard set by the regulation No. 14499 KJ14/DJM/2008. The reaction kinetics parameters of the liquid and gas activation energy are of 127,025.79 J/mol and 73,766.93 J/mol, respectively. Meanwhile, the liquid and gas pre-exponential factors are 8,590 and 257,respectively.

Modeling and optimization of the pyrolysis oil production process from polypropylene for the production of aviation kerosene

“…This temperature range was used in order to separate fractions that could possibly include aviation kerosene, which could possibly be part of the pyrolyzed oil. The factors were chosen according to the works developed in the literature (Erawati et al 2020). Through CG-MS Agilent 7820 column C18 it was possible to identify the closest proximity of the oil by comparing the peak areas with diesel, gasoline and aviation kerosene standards.…”

Thermocatalytic Conversion of Plastics into Liquid Fuels over Clays

“…They found that the yield of aromatic hydrocarbons increases with the reuse of the catalyst, which is associated with an increase in particle size [ 16 ]. The optimal size of kaolin particles was investigated in the work of Erawati et al, where it was established as 7.5 × 6.5 cm [ 19 ].…”

“…In summarizing, the highest liquid yields described in the articles concerned with kaolin catalysts for different plastics are 78.7 wt% for HDPE over nitric acid-treated kaolin [ 14 ], 99.82 wt% for LDPE on neat kaolin powder [ 19 ], 92 wt% for PP on sulfuric acid-treated kaolin [ 25 ], and 96.37 wt% for PS over pristine kaolin [ 29 ]. Quite expectably, the most efficient catalysts were obtained using acidic treatment, which led to the generation of a sufficient number of acidic sites.…”