Experimental Research Of Lignite Plastic Property Improvement Modification By Catalytic Moderate Non-liquefaction Hydrogenation

Coal hydrogenation technology is an important way of coal processing and utilization, carrying with hydrogenation under mild conditions with no caking property low metamorphic coal, what can be made into a certain caking property and can be used in the modification of coking coal resources, which is of great significance. In this article, we will add catalysts and plastic with rich hydrogen in the lignite hydrogenation process, trying to change the chemical structure of lignite for getting sticky modification effect.On the autoclave hydrogenation, lignite coal hydrogenation, catalytic hydrogenation and adding polypropylene (PP) plastic blending catalytic hydrogenation experiments were researched in hydrogen atmosphere. Studying the possibility of a catalytic hydrogenation reinforced adhesion and selection of reaction conditions, at the same time, the structure characteristics of modified coal respectively has been studied in detail by measuring the caking property of coal, using IR analysis technology, Chromatography analysis technology, thermal analysis and making a detailed analysis of the functional groups of the hydrogenation coal, in order to through the structural characteristics of change in modified coal to make further analysis to the hydrogenation mechanism. The main results are as follows:1. The results indicate that the hydrogenation and catalytic hydrogenation under reaction temperature350℃, hydrogen pressure10Mpa and8hours reaction time have obvious effects on the changes of lignite coal structure. The content of aliphatic hydrocarbon in coal structure and pyrolysis reactivity were improved significantly. The plastic property of lignite after moderate catalytic hydrogenation was sharply enhanced, caking index of hydrotreated coal increasing from zero to19.21. The effect of using catalyst in hydrogenation processing on the indexes of caking property improvement is higher than that of non-catalytic hydrogenation.2. Lignite, ferrous sulfate catalyst and plastic alone or together pyrolysis experimental data showed that lignite overlapped with plastic pyrolysis temperature range, and ferrous sulfate analytical reagent had little weightlessness in the former two interaction; adding the catalyst makes the percentage of weightlessness of the coal sample at low temperatures increase, reduces weightlessness percentage in the period of the temperature, moves forward the temperature of maximum weight loss rate, and the weight loss rate also increases; the maximum weight loss rate of mixed catalytic hydrogenation coal samples and the corresponding temperature and the weight loss rate is larger, compared to without plastic.3. Under the condition of350℃catalytic hydrogenation reaction, there were hydrogen competitive reactions between the polypropylene decomposition to produce free radicals with coal and the liquid produced by plastic melting and decomposition packaged the coal particles, inhibiting the hydrogenation of coal particles. Compared with the unadded plastic hydrogenation reaction of coal, adding polypropylene went against the catalytic hydrogenation of lignite. Hydrogenation reaction temperature had a significant impact on improving its caking property in catalytic hydrogenation of lignite, and at the right temperature, coal hydrogenation can obtain higher bond index. Under reaction temperature400℃, catalytic hydrogenation had little effect on improving coal caking property; under the condition of350℃, hydrogenation reinforced adhesion effect was remarkable.