Dissolution of lignite in ionic liquid 1-ethyl-3-methylimidazolium acetate

• EMIA shows high performance on the dissolution of lignites.
• Extraction temperature and lignite type significantly affect extraction behaviors.
• Extraction yield increases with the increase of carboxyl content of lignites.

The extraction behaviors of three lignites with ionic liquid (IL)-1-ethyl-3-methylimidazolium acetate (EMIA) were studied in this work. The effects of extraction temperature and lignite type on extract yield and product compositions were primarily investigated. Also the relationship between the extract yield of lignites and the quantities of oxygen-containing functional groups in lignites was investigated. It was found that EMIA is a more efficient solvent for the dissolution of lignites compared to the performance of 1-butyl-3-methyl-imidazolium chloride (BMIC). Extraction temperature and lignite type significantly affect extraction behaviors of lignite with EMIA. The extract yield of lignites with EMIA increases with the quantity of carboxylic groups in lignite increases. Only a small amount of aliphatic alkyl structure components are extracted at low temperature. More aromatic structure components are extracted by EMIA at high extraction temperature.

Figure optionsDownload as PowerPoint slide