Reactivity And Kinetics Of Ultra-fine Coal Powder In Photo-catalytic Oxidation

How to utilize coal resource with high efficiency, cleanliness and high-attached value is a strategic problem in grand development of West China. Due to "white pollution" becoming more and more serious and human focusing more and more on environment protection, the R & D of degradable materials are becoming a hotspot. The preparation of coal-based degradable materials is one effective way of coal in non-fuel utilization and high-attached value processing transformation. The technique key problem of accurate control in the degraded periods of the coal-based degradable materials is to clarify the reactivity and kinetics in coal photo-catalytic oxidation.In this paper, the grades of ultra-fine coal powder's uniformity and coal granular surface morphology were characterized by the fractal dimensions. The functional groups of ultra-fine coal powder were studied by Fourier Transform Infrared spectroscopy (FTIR) and curve-fitting analysis. The results showed that oxygen-containing functional groups and content of aliphatic hydrogen (Al-CH) decreased, whereas the degree of ring condensation and content of aromatic hydrogen (Ar-CH) increased with increasing coal rank. Meanwhile, main hydrogen bonds in coal structure were OH-OH, cyclic OH tetramers and OH-ether O. With increasing coal rank, OH-OH and cyclic OH tetramers reduce, but OH-ether increases.The reactivity and their affecting factors of different rank coals in photo-catalytic oxidation were firstly systemically studied in a self-made photo-catalytic oxidation reactor on the basis of the combination of coal structure and photochemistry in theory, fractal analysis and modern characteristic methods. The experimental results indicated that the temperature, rate of oxygen flow, ultraviolet radiation intensity and coal particle's size were important exterior factors in coal photo-catalytic oxidation, the reaction procedure of coal photo-catalytic oxidation could be divided into three periods. Low-rank coal has higher activity than high-rank coal in photo-catalytic oxidation. It can be deduced that there is the photolysis reaction of Norrish â…¡ of coal macromolecule in photo- catalytic oxidation because...