Study Of The Coal Pyrogenic Reaction Kinetics And Higher Temperature Rapid Liquefaction Reaction Character

In this thesis, the process and law of high temperature rapid liquefaction were studied during liquefying Yang cun coal and Sheng mu coal, moreover their reaction characteristics were discussed.In chapter one the research actuality of coal liquefaction is summarized . experiment apparatus and methods are introduced in chapter two.In chapter three the pyrogenation character and kinetics of coal were researched. From molecule structure of coal, coal reaction character was described by aromatic ring , hydrogenation aromatic ring , alkane , alkane bond , oxy-group. Kinetics model of coal pyrogenation was obtained by analysing the data of TGA experiment . According to log[-log(l-a)]=log(AE/R )-0.054E/T-2.284. The result shows that coal pyrogenation reaction concludes three one-order reactions. Namely two pyrogenations and one polycondensation. On calculating pyrolysis characteristic values of coal , apparent activation energy(Ea) of various stages, reaction kinetics constant (K), pre-exponent (A) , maximum weightlessness rate(Rm), weight loss percent (F), reaction active index(Ra).they can be regarded at the index of coal pyrolysis reactive activity .The bigger Ra or the Rm, the better reactive activity of coal .The value of Tb(initial reaction temperature) and Tf(final reaction temperature) was defined through the curves of TG and DTG . It decides the upper limit of reaction temperature of routine and high temperature rapid liquefaction . finally, the section of coal liquefaction reaction temperature is 390-480℃ of Yang cun coal and 425-525℃ of Sheng mu coal separately .In chapter four , in the light of the theory of three stages of coal liquefaction, 1) high reactivity stage 2)low reactivity stage3)polycondensation stage . The effect of temperature, reaction time ,catalyst on high temperature rapid liquefaction of two kinds of coal . Experimental results indicates there is high conversional rate in short reaction time and high temperature of coal liquefaction .the coal conversion increases along with the extension of reaction time , exceeding the final temperature of coal liquefaction(Tb), the coal conversion declines . At the beginning of high temperature stage, the coal conversion with catalyst is higher than that without catalyst. the effect of catalyst weakens owing to the extension of reaction time and the enhancing of temperature. The catalyst has two functions possibly ,it accelerates hydrogenation reaction at the initial stages of reaction , and the same time it promote polycondensation along with the extension of reaction time . the best reaction condition changes with the effective factors .The preasphltene and benzene solubles of coal liquefaction production convert into each other at some reaction conditions .In chapter five, by analyzing the data of coal liquefaction ,the apparent active energy of two coal was gained . Eayangcuncoai=7.548KJ/mol, Eashengmucoai=13.391KJ/mol . The lower values of Ea provide the base of rapid liquefaction , simultaneity two coals and reaction residue , liquefaction production were analyzed, the mechanism of coal high temperature rapid liquefaction is studied.