Research on Supercritical Methanol Treatment of Lignite


China has rich lignite reserves which are the proper resources to be liquefied. As its low coalification degree, much hydrogen is wasted. Solvent extraction can save hydrogen and improve its liquefaction performance. The paper studies supercritical methanol treatment of lignite with a device at high temperature and pressure. Experiments mainly focus on the effects of temperature, pressure, catalysts and pretreatment ways on the extraction rate. Results indicate that the extraction rate increases with raising of temperature and pressure below 330 ℃,10 MPa. When temperature exceeds 330 ℃, extraction rate decreases slightly.  After swelling pretreatment in methanol for 8 h, the lignite is treated for 60 min at 330 ℃,8.2 MPa with NaOH as catalyst(1%wt).  The weight ratio of methanol/ Xilinhaote lignite is 5/1.  Under these conditions, the extraction rate can reach 22.88%.


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H. Luan, A. Wang, Q. Zhang and F. Chen, "Research on Supercritical Methanol Treatment of Lignite," Advances in Materials Physics and Chemistry, Vol. 2 No. 4B, 2012, pp. 158-161. doi: 10.4236/ampc.2012.24B041.

Conflicts of Interest

The authors declare no conflicts of interest.


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