Selective catalytic ethanolysis of C-O bonds in lignite-related model compounds and Xilinguole lignite over difunctional Ni/HZSM-5 in H2-free system

Catalytic cracking of C-O bond is one of the important strategies for conversion of lignite into soluble organic matter. Ni/HZSM-5 was prepared by a modified deposition precipitation method with the Ni mass ratio ranging from 5% to 20% and evaluated by catalytic cracking benzyloxy benzene (BOB) and benzyl ether (BE). BOB was completely converted in ethanol over Ni15%/HZSM-5 under 1 MPa N2 at 240 degrees C for 2 h, while BE was completely converted at 180 degrees C. Ethanol could be activated to CH3CH2O. and H. over Ni nanoparticles supported on HZSM5, which cleaved the C-O bond in BOB and BE. Additionally, the Ni15%/HZSM-5 was also successfully applied in catalytic ethanolysis of resides from ethanolysis Xilinguole lignite (XL) without H2 at 300 degrees C. The soluble portion yields from ethanolysis of XL and catalytic ethanolysis of residue are 47.8% and 15.1%, respectively. Soluble portion 1 (SP1) and catalytically soluble portion 1 (SP1C) were identified by gas chromatography/mass spectrometry. Different from SP1 mainly containing esters and phenols, SP1C is mainly composed of alkanes, arenes, and esters. In conclusion, catalytic ethanolysis of lignite in H2-free system is a potential way to cleave C-O bonds and prepare lignite-derived organic chemicals.