Following the structure and reactivity of Tuncbilek lignite during pyrolysis and hydrogenation

Abstract

Available online xxxxCombustion, pyrolysis and hydropyrolysis reactivity of Tuncbilek lignite was monitored by temperature programmed pyrolysis (TPP) under pure nitrogen flow, temperature programmed oxidation (TPO) under air flow and temperature programmed hydrogenation (TPH) under hydrogen flow at atmospheric pressure in a packed bed reactor.The structures of the organic and inorganic components were analyzed by NMR spectroscopy and XRD. Only methane and hydrogen were the main products of TPP while small amounts of CO and CO 2 were also observed. Solid-state 1 H and 13 C CPMAS and 1 H liquid Nuclear Magnetic Resonance (NMR) Spectroscopy of the pristine lignite, as well as tar and char products of pyrolysis and hydrogenation (hydropyrolysis), revealed similar tar compositions. TGA of pyrolysis chars indicated that there were more residual volatiles in hydropyrolysis char in comparison to pyrolysis char. Elemental analysis of pyrolysis and hydropyrolysis chars revealed that 25% of sulfur was lost during pyrolysis, whereas N 90% of sulfur was lost during hydropyrolysis indicating efficiency of atmospheric pressure hydropyrolysis for both desulfurization and tar production. Volatile matter and fixed carbon, mostly aromatic, gave rise to distinct oxidation peaks during TPO. The oxidation peak due to volatiles was missing from TPO of pyrolysis char as well as from organic contents determined by NMR spectroscopy.

Oxygen Transfer Ability of Co-Pb Metal Oxides during the Chemical Looping Oxidation of Tuncbilek Lignite

“…Coal samples were obtained from Turkish Coal Enterprises (TKI) Tuncbilek Lignite Establishment in Turkey. The details of sample preparation and characterization were explained in our previous papers (Kanca, Dodd, Reimer, & Uner, 2016;Kanca & Uner, 2019).…”

“…60.5% weight loss was recorded during TGA under air flow. This weight loss was attributed to the combustible materials in coal structure (Kanca, 2013;Kanca et al, 2016). Approximately 3% moisture present in the coal sample was not taken specifically into account in these calculations, introducing 3% error in weight estimations associated with the moisture.…”

Investigation of the liquefaction possibility of Ermenek lignite as an alternative clean energy source

“…They also observed that the concentration of nitrogen-containing components in the coal liquid with increasing temperature and reaction time [6]. Kanca et al (2016) was studied the liquefaction of Tunçbilek lignite. They determined that the sulfur content, which was 5.4% in raw lignite, decreased to 0.5% in the solid and liquid products they obtained as a result of the liquefaction experiments [7].…”

Investigation of the improvement of Sivas-Kangal lignites liquefaction product yields

“…For this reason, various processes such as pyrolysis and liquefaction have been tried to produce solid and liquid fuels or chemical raw materials from coal. There are many studies on this subject in the literature [1][2][3][4][5][6]. The structure of coal is different from that of the hydrocarbons in petroleum.…”