Study On The Photo-catalytic Oxidation Characteristics Of Shenfu Super-tiny Coal

This article intended to provide theoretical foundation for the preparation of coal-based composites through the investigation of the photo-catalytic oxidation characteristics of different density grades of Shenfu super-tiny coal. Two grades of 1.375¹.4 grade and bigger than 1.4 grades are mainly studied by the self-controlled photo-catalytic oxidation reactor, the two grades is abundant in Shenfu coal. Product of coal oxidation reaction are studied by its total yield of humid acids, swelling capacity, mean relative molecular weight at cross linking points and elemental analysis, as well as their FTIR spectra. The research shows that three stages are divided during photo-oxidation of every grade: early stage of quick oxidation rate, transition stage of slow-falling oxidation rate and level-off stage of stable oxidation rate. Characteristics of photo-oxidation is weaker for D3 grade with higher mineral substance, aromaticity and aryl replace degree and because of photo-catalysis of abio-mineral substance and aroma ring, more aether is formed in photo-oxidized solid product. While that is stronger for D2 with inferior aryl replace degree, but more methylene and aliphatic side chain. Adding rare-earth metal ions and transition metal ions to coal both help photo-oxidation of coal. Rare-earth metal ions of Ce3+,La3+ can greatly accelerate humic acid form; Transition metal ions Fe3+,Ni2+,Co2+ especially Ni2+ have a remarkable effect on weight-loss during coal photo-oxidation degradation, while composite of rare-earth metal ions and nano- TiO2 may greatly boost up effect of photo degradation. Photo-oxidation reaction of Shenfu coal first induces by active function group, but it shows a series process origin humic acid―photo degradation―new humic acid―photo degradation……for Shenfu coal. CO₂ is staved to form because of stabilized coordination effect between metal ions and humic acid, but humic acid form accelerated, and it has a photo sensitizer in accelerating organic matter in coal to oxidize into carbonyl compound, and break chain by the mechanism of Norish I and Norish II to quicken up photo-oxidation degradation of coal organic substance.