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

Öz

In recent years, converting and using coal into the most suitable product according to its properties has emerged as a modern approach. Among the main processes applied to coal are low and high-temperature carbonization, gasification and liquefaction. In coal liquefaction, coal is broken down into free radicals using hydrogen donor solvent and catalyst under high temperature and pressure conditions. Later, these radicals can be used in the production of both liquid fuel and chemical raw materials by being saturated with hydrogen. This study aims to improve the yields of Sivas-Kangal lignite liquefaction products (char, preasphaltene, asphaltene, oil-gas). For this purpose, firstly raw coal, then spiral enriched clean coal liquefaction experiments were carried out. The chemical characterizations of the obtained products were determined by proximate and ultimate analysis. The composition of the oil was identified by GC-MS. As a result of the enrichment, the char yield decreased by 16.5% whereas the oil+gas yield increased by 14.64%. Total conversion increased from 31.74% to 48.24%. It has been concluded that the enrichment process has a positive effect on the liquefaction yields.

Anahtar Kelimeler

• Asphaltane
• Lignite
• Liquefaction
• Oil
• Preasphaltane

Kaynakça

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