Study On Process And Kinetics Of Phenolic Compounds From Coal Pyrolysis Tar In Yulin

In order to develop a simple and economic method of extracting phenolic compounds from coal tar at meso-low temperature and improve the economic benefit of semi-coke industry in the YuLin District. In this paper, we took medium temperature coal tar of ShenMu in YuLin City as raw material and studied the carbolic oil distillate fraction of coal tar<220℃ which was got by using precision distillation.Through optimizing the Alkali extraction method of concentrating the mixed phenolic components in coal tar, achieved the goal of full enrichment and reducing losses. Silicon etherified reagent pretreatment was used to get ethers derivatives from the mixed phenolic components. Taking the ethers derivatives as the main analysis object, analysed the kinds of the individual phenol of mixed phenolic sample indirectly and qualitatively. Using the area normalization method and the external standard method determined the content of the individual phenol of mixed phenolic sample indirectly and quantitatively. The process of coal tar alkali-extracting phenol was researched from macro perspective, verified the feasibility and efficiency of extracting phenolic compounds from coal tar, which used NaOH aqueous cleaning and combined CO₂ acidification. The experimental results showed that the optimal alkaline cleaning condition was:40℃,10% and 5 min, the minimum ratio of alkali and oil was 0.08, the ratio of water and oil was 0.6 to 1.2. When the reaction reached equilibrium by using the operation of CO₂ acidification, the yield of phenol was 21.3%,95% of the limit of yield of phenol.Through the design of orthogonal test, determined the main factors of alkaline cleaning process which affected the yield of extracting phenol in the order of significance was:the temperature of alkaline cleaning>the concentration of alkaline liquor> the time of alkaline cleaning.Established the experiment method of studying the kinetic processes of CO₂ acidolysis reaction of sodium phenolate. Selecting five kinds of typical sodium phenolate: sodium phenate, sodium o-cresol, sodium p-cresol, sodium 2,4-xylenol and sodium 5-indan phenol which were from the mixed sodium phenolate, investigated the effects of the volume fraction of CO₂ on the reaction rate of sodium phenolate respectively, determined the intrinsic reaction rate constant of the sodium phenolate under different volume fraction of CO₂. Further, taking sodium cresol as representative compound, the effects of the temperature of reaction, the initial concentration of sodium phenolate and the total flow of feed gas, etc. on the acidolysis reaction rate which were studied indetail. The experimental results showed that under the conditions of the same temperature and the same volume fraction of CO₂, the order of acidoysis reaction rate constant of five types of sodium phenolate always was:sodium phenate> sodium o-cresol> sodium p-cresol>sodium 2,4-xylenol>sodium 5-indan phenol. Processed multivariate linear regression of the experimental data of sodium cresol, the macro kinetic equation of sodium cresol acidolysis reaction was:...