Study On The Adsorption Process And Mechanism Of Adsorbent For Main Impurities In Phenol

Phenol is an important organic raw material in the chemical industry.Its downstream products are mainly phenolic resin,salicylic acid,and bisphenol A.At present,the methods for producing phenol in the world mainly include cumene method,benzene sulphonation method,and benzene direct oxidation method,over92 % of the phenol is produced by the cumene process.In the production of phenol from the cumene process,the decomposition and oxidation of cumene is accompanied by the occurrence of many side reactions,resulting in a variety of organic impurities,which seriously affect the phenol color,purity and other indicators,and thus affect the production of phenol downstream products and applications.In addition,the presence of these impurities can also poison certain catalysts in the subsequent process.In recent years,with the rapid development of industries such as automobiles and pharmaceuticals,the demand for downstream products of phenol has gradually increased,and the corresponding demand for phenol is also growing rapidly.Therefore,removing the organic impurities in phenol and increasing the purity of phenol is an urgent problem to be solved at present.In this paper,the adsorption mechanism of impurities on the resin were studied,and the adsorption properties of the acidified activated carbon on the impurities in phenol was explored,which provided technical support and new ideas for the industry to further refine the phenol.In this paper,the CT151 resin as adsorbent,solid phase micro-extraction(SPME)and gas chromatography-mass spectrometry(GC-MS)method was used to study the main impurities in the phenol refining process,such as mesityl oxide,2-methylbenzofuran,2,4-diphenyl-4-methyl-1-pentene adsorption mechanism,at the same time,the adsorption properties of acidified activated carbon for2,4-diphenyl-4-methyl-1-pentene was explored.Fourier-transform infrared spectroscopy(FTIR)was used to characterize the groups and structures before and after the CT151 resin adsorbed impurities.Through the static adsorption experiments,the best conditions of SPME were selected.At the same time,the influence of adsorption time on the adsorption properties of CT151 resin and activated carbon wasinvestigated.The adsorption equilibrium data were fitted and analyzed with Langmuir,Freundlich isotherm equations and two adsorption kinetic models.The results indicated that the SPME used optimum extraction conditions were extraction time of15 min,extraction temperature of 30 ℃ and resolution time of 4 min.In the static adsorption experiment,the best adsorption time of CT151 resin for mesityl oxide,2-methylbenzofuran and 2,4-diphenyl-4-methyl-1-pentene was 4 h,and the removal rates were 60.48 %,68.52 % and 94.61 %.The adsorption equilibrium time of2,4-diphenyl-4-methyl-1-pentene on sulfuric acid acidified activated carbon was 1 h,and the removal rate was 82.17%.Adsorption isotherms of CT151 resin to mesityl oxide,consistent with Langmuir adsorption model;adsorption isotherms for2,4-diphenyl-4-methyl-1-pentene,the Freundlich equation has a good fitting effect;adsorption isotherms for 2-methylbenzofuran,Langmuir equation and Freundlich equation can describe the adsorption behavior of CT151 resin to its.At the same time,the adsorption kinetics of CT151 resin to adsorbates are in accordance with the pseudo-second-order kinetic model,indicating that CT151 resin adsorbs mesityl oxide,2,4-diphenyl-4-methyl-1-pentene,2-methylbenzofuran are chemical adsorption.Sulfuric acid acidified activated carbon has good adsorption effect on2,4-diphenyl-4-methyl-1-pentene.At the same time,the adsorption isotherm of2,4-diphenyl-4-methyl-1-pentene adsorbed by sulfuric acid acidified activated carbon accords with the Freundlich model,and the adsorption kinetics accords with the pseudo-second-order kinetic model.By studying the mechanism of resin adsorption impurities,it provides the theoretical basis for the phenol refining process in the chemical industry,and can be widely applied to the actual production of phenol refining.The use of acidified activated carbon to refine phenol can provide an economical and effective method for the industry.