Study On Thermal Risk Of Anthraquinone Nitro Compounds And Their Mixtures

The production of anthraquinone dye intermediates in the dye field is relatively large and the application is wide.As the basic process for the synthesis of anthraquinone dyes,the nitrification process itself and its products have the risk of combustion and explosion.The product anthraquinone nitro compounds are used as dye intermediates and may also exist as hazardous solid wastes.In recent years,related accidents have occurred frequently and frequently,so it is necessary to study their thermal hazards for storage and transportation.Provide reference for safe operation in.The paper selects four solid materials that will be produced in large quantities during the production of anthraquinone dye intermediates: anthraquinone,1-nitroanthraquinone,1,5-dinitroanthraquinone,1,8-dinitroanthraquinone is used as the research object to study the thermal hazards of these substances and their mixtures.Obtain the thermal decomposition characteristics and identify the decomposition reaction type through the differential scanning calorimeter(DSC)test;combine the Friedman method and model fitting method to solve the kinetic model and parameters;finally predict the thermal safety parameters based on the obtained kinetic model.For the four substances,anthraquinone has no exotherm within the test temperature range;the other three anthraquinone nitro compounds have thermal decomposition,and the specific heat release is: 989.67 J/g(1-nitroanthraquinone),1848.35 J/g(1,5-dinitroanthraquinone),1733.55 J/g(1,8-dinitroanthraquinone),are all greater than 800 J/g,the severity of the thermal runaway reaction is "catastrophic",and the decomposition of the three has autocatalytic properties.The activation energies of the three calculated by Friedman method vary within the range of 148 k J/mol-165 k J/mol,169 k J/mol-294 k J/mol,155 k J/mol-213 k J/mol,indicating that the decomposition of 1-nitroanthraquinone is relatively simple,while the decomposition of1,5-dinitroanthraquinone and 1,8-dinitroanthraquinone is more complicated.The "autocatalysis" of 1-nitroanthraquinone and the "n-order + autocatalysis + autocatalysis" reaction model of 1,5-dinitroanthraquinone were established,and the "autocatalysis +autocatalysis" reaction model of 1,8-dinitroanthraquinone.For the mixture,the decomposition process of the mixture under different mixing conditions is more complicated.The kinetic analysis results of Friedman method and model fitting method show that the decomposition process of the mixture has a multi-step autocatalytic reaction.And the decomposition process of the mixture tends to be simple with the increase of the anthraquinone content.Anthraquinone itself does not emit heat but can affect the thermal behavior of such substances.The prediction results of thermal safety parameters show that the thermal stability of the three anthraquinone nitro compounds after mixing will decrease,and the addition of a small amount of anthraquinone can improve the thermal stability of the mixture.The work in this paper not only provides the thermal risk parameters of anthraquinone nitro compounds,but also has a good reference significance for the research on the thermal safety of hazardous wastes from related nitrification processes.