Study On The Preparation Of Granular Activated Carbon For Sucrose Decolorization By Coal Blending Method

Sucrose,as a key material,the market’s demand for the quality of sucrose is also increasing.In order to improve the quality of sucrose,it is necessary to remove colored substances more efficiently.As an efficient porous adsorption material,granular activated carbon has the advantages of low pollution,high mechanical strength,and easy recycling and regeneration.This thesis uses bituminous coal from Xinjiang region as the main raw material to prepare granular activated carbon for the decolorization of sucrose stock solution using two molding methods:briquetting and extrusion.The advantages and disadvantages of the two molding methods are analyzed.The influence of raw coal blending ratio on the performance of activated carbon was studied through coal blending method,and the influence of production process conditions on the performance of activated carbon was also studied.The specific research content and conclusions are as follows:1.Using 3J and 2T bituminous coal provided by Xinjiang chemical enterprises as the main raw materials,compressed activated carbon was prepared through coal blending and briquetting methods.The correlation between ignition loss rate,iodine value,methylene blue value,strength,and molasses value was studied.The results show that the activated carbon prepared with 2T as the main raw material has a higher molasses value.When the coal blending ratio is 2T bituminous coal:4H gas fertilizer coal=60:40,the activated carbon molasses value prepared can reach 347 mg·g^-1,but the strength of the activated carbon is only 55.8%.The molasses value of pressed activated carbon has a positive correlation with the proportion of loss on ignition and methylene blue value,while it has a negative correlation with strength.The correlation with iodine value is not significant.2.In the process of preparing activated carbon by extrusion method,the effects of the addition of 3J bituminous coal,2T bituminous coal,and 4H gas fertilizer coal on the iodine value,methylene blue value,and molasses value of activated carbon were investigated through D-optimal mixture design.The results show that the strength of activated carbon prepared by extrusion method can reach over 90%,and its molasses range from 122 mg·g^-1to 146 mg·g^-1.Similarly,the addition of 2T bituminous coal can also improve the molasses value of extruded activated carbon,while the addition of 4H gas fertilizer coal has no significant impact on the various performance indicators of activated carbon.The final method for forming activated carbon was determined,and the dosage of 2T was determined to be 10 g to 30 g,while 4H gas fertilizer coal was not selected for blending.3.The effects of material parameters（coal blending ratio,asphalt addition,binder addition,and water flow rate）and temperature parameters（carbonization temperature,carbonization heating rate,activation temperature）on the properties of activated carbon in the preparation process of activated carbon were studied through orthogonal experiments and single factor experiments,respectively.The results show that the average performance index of activated carbon is the best when the material parameters are 3J bituminous coal,2T bituminous coal=70:30,the amount of asphalt added is 12 g,the amount of binder added is 4 g,and the water flow rate is 0.5m L·min^-1.The activated carbon strength is 92.2%,the iodine value is 797 mg·g^-1,the methylene blue value is 66.2 mg·g^-1,and the molasses value is 138 mg·g^-1.The optimal temperature parameters are as follows:the carbonization temperature is650^oC,the carbonization heating rate is 18^oC·min^-1,and the activation temperature is930^oC.The activated carbon molasses prepared have the highest values,151 mg·g^-1,145 mg·g^-1,and mg·g^-1,respectively.There are 42 figures,23 tables and 87 references in this thesis.