Preparation Of Foamed Ceramic Insulation Materials By Using Spent FCC Catalysts

Fluid catalytic cracking(FCC)is the main preparation process of petroleum catalytic cracking.During the catalytic cracking process,a large amount of spent catalysts,called spent FCC catalysts,that cannot meet the needs of catalytic cracking are produced.Spent FCC catalysts have great damage to the economy and the environment,and the current method of processing spent FCC catalysts has the disadvantages of difficult treatment methods and the inability to use solid waste in large amounts.Therefore,the method of using spent FCC catalysts to prepare foamed ceramic was studied in this paper.Foamed ceramic was prepared by direct foaming method,using the FCC spent catalysts as raw material,glyceroltripalmitate as foaming agent,alumina fiber as reinforcement.The structure and performance of foamed ceramic was characterized by microscope,XRD and universal testing machine.The orthogonal test was set to explore the effects of powder ratio,foaming process,etc.on the bulk density,porosity and average pore size of foamed ceramic.And the effects of sintering temperature on heat insulation performance,linear shrinkage rate and compressive strength were also explored.It is tested that when the FCC spent catalysts:alumina powder:mixed starch:glyceroltripalmitate:alumina fiber:water:silica sol:Xanthan gum=70g:35g:14g:4g:12g:31m L:35m L:8m L,the foaming time is 50min and the foaming temperature is 60℃,the foamed ceramic with lower bulk density and higher porosity can be prepared.When the FCC spent catalysts:alumina powder:mixed starch:glyceroltripalmitate:alumina fiber:water:silica sol:Xanthan gum=70g:30g:14g:4g:12g:36m L:30m L:8m L,and the foaming temperature is50℃,the foamed ceramic with smaller average pore size can be prepared.It is tested that after 1500℃×12h sintering,the porosity is 80.5%,and the bulk density of foamed ceramic is 0.58 g/cm~3,of which the FCC spent catalysts:alumina powder:mixed starch:glyceroltripalmitate:alumina fiber=70:30:14:4:12.The thermal insulation performance of the foamed ceramic at 1500℃×12 h sintering is better than that of the foamed ceramics prepared at 1400℃×12 h sintering and at 1600℃×12 h sintering.The thermal insulation performance is better than that of common alumina plate with a bulk density of 0.60 g/cm~3.And the thermal conductivity at 800℃is 0.16 W/(m?K),which is lower than that of the common alumina plate,which is 0.18 W/(m?K).The cost of foamed ceramic insulation board is estimated.The cost of raw material is 7890 yuan/t,which is more competitive than common insulation materials board.The effect of sintering temperature on the linear shrinkage and compressive strength of the foamed ceramics was also tested.As the heating temperature increases,the linear shrinkage rate of the foamed ceramic increases gradually.After 1600℃×12 h sintering,the linear shrinkage rate is smaller,which is 1.27%on 1400℃heating.As the sintering temperature increases,the compressive strength of ceramics increases.After 1600℃×12 h sintering,the compressive strength is higher,which is 3.11 MPa.