Experimental Study on Microwave Pyrolysis of an Indonesian Low-Rank Coal

Abstract

Microwave pyrolysis of an Indonesian lignite is investigated in this study. The effects of experimental parameters, such as microwave receptor/coal ratio, residence time, temperature, microwave power level, and coal particle size, on the yield and characteristics of coal pyrolysis products were studied systematically. Fe3O4 was used as the microwave receptor. The compositions of oil products from the microwave pyrolysis were analyzed using gas chromatography–mass spectrometry. The experimental results showed that a higher microwave power led to higher heating rates and higher volatile matter yields. The yield of gaseous and oil products increased with increasing the microwave receptor/coal ratio and microwave power. The oil products were complex mixtures of organic compounds with a variety of chemical groups. The yields of aromatic compounds, including phenol and naphthalene, increased significantly with the pyrolysis time. The oil products contained 17.27% saturated aliphatic species, while the aromatic compounds accounted for 45.5%, and polar groups formed 25.84% of pyrolysis oil. As pyrolysis proceeded, Fe3O4 was reduced to elemental Fe at the later stages of microwave pyrolysis, as evidenced by X-ray diffraction and energy-dispersive X-ray analyses. Scanning electron microscopy analysis showed that the morphology of the microwave receptor (Fe3O4) changed as a result of reduction.

Resource recovery from synthetic polymers via microwave pyrolysis using different susceptors

“…Of the different pyrolysis technologies available, pyrolysis of a variety of feedstocks [2,3,5,6,[8][9][10][11][12]. These include, biomasses such as wood [12,13], corn stover [10,[12][13][14], empty fruit bunch [15,16], wheat straw [17,18], rice straw [19][20][21][22], sugarcane bagasse [23], douglas fir [24], and coffee hulls [25], coal [11], municipal solid wastes and sewage sludge [26][27][28][29], algae [9,30,31], and synthetic polymers like poly(vinylchloride) [32], high density polyethylene (HDPE) [33], polypropylene (PP) [33], polystyrene [34], poly(ethyleneterephthalate) [35] and waste tyres [36,37]. Recently Beneroso et al [38] showed that by integrating the drying operation with microwave pyrolysis, the production of syn gas from organic wastes can be maximized.…”

Microwave assisted pyrolysis of plastic waste for production of fuels: a review

“…But the IR thermometer sensors can only measure the surface temperature of the reactor which is lower than the temperature of the reaction mixture [15]. In this context only few studies have been able to measure the temperature within the reaction mixture [35][36][37]. On the other hand, the use of fiber optic device is not possible since it can measure temperatures only up to 400°C [38].…”

Influences of exchangeable metallic species on solvent extraction of Xiaolongtan lignite and characterization of the separated portions

“…GC/MS analyses (Fig. 7) show that different group components of extracts are obtained from Ca-0.1 or De-H. A semi-quantitative method is applied to compare the product distributions in different extracts [35]. An obvious character of the profile is the high abundance of alkanes and alkenes (AAs) in extract obtained from extraction of Ca-0.1 with n-hexane, which indicates that n-hexane is effective for extracting aliphatic compounds.…”