Preparation Of Carbon Foam By Using Components Group Separated From Coal And Modulation Of Foam Pore Structure

Under atmospheric pressure and inert atmosphere conditions, carbon foams were derivedfrom loose medium components, which separated from raw coal by all-components groupseparation, by one-step process. The influences of carbonization process, smaller-moleculecomponents contents and coal where loose medium components came from on foam porestructure were investigated; Activated carbon foams were prepared from loose medium com-ponents, semi-carbon foams and carbon foams by activation with KOH. The two-step prepa-ration technology based on semi-carbon foams and carbon foams was studied when orthogo-nal experimental design was conducted as well. The influences of carbonization temperature,activation temperature, activation holding time and alkali carbon ratio on specific surface are-as, total pore volumes and pore size distributions were investigated. The feasibility for acti-vated carbon foams were applied to electrode materials of supercapacitors was discussed pre-liminarily by electrochemical testing.The results showed that carbon foams prepared at850~1100℃were equality, abundantand connectivity in their foam pore with maximum total pore volume and porosities reachedto4.7cm3/g and83.5%. In addition, their bulk density and apparent density were very low.Among those carbonization conditions, the influences of first-step constant temperature timeand second-step constant temperature time on the foam pore structure of carbon foams weregreater than second-step heating-rate and second-step temperature. The foam pore size ofcarbon foams prepared by using loose medium components which extracted by solvents toreduce the smaller-molecules components content was decreased significantly. The wholestructure of these carbon foams was compact and meanwhile the compact degree was posi-tively associated with their extraction rate. Carbon foams had obvious different structurewhen prepared by loose medium components from different coals.When prepared from powdered semi-carbon foams mixing with KOH, activated carbonfoams could obtained superior specific surface areas which could up to1510cm2/g and totalpore volumes which could up to0.8384cm3/g. Micropore and mesopore were focused ontheir pore sizes which concentrated on0.95~1nm and2~5nm, respectively. The content ofmesopore was20~50%while the content of macropore was low. The electrochemical perfor-mance of supercapacitor which made by activated carbon foam which was named ACF-7isfine, which the specific capacitance is109.2F/g. This proved that activated carbon foamswere suitable for electrode materials of supercapacitors.There were eighty seven figures, twenty eight tables and fifty nine references in this pa- per.