Study On The Preparation Of Wood Formed Activated Carbon With Chemical Method

In this subject, Formed activated carbon with high performance was made, only usingplastics material produced by sawdust itself as a binder during pyrolysis process, instead ofadding additional binder. Plasticizing mechanism during the process and the technologicalconditions in two different chemical reagents—H₃PO₄and ZnCl₂were studied to providescientific data and theoretical basis for the preparation of high abrasive resistance granularactivated carbon.An amount of reducing sugar is produced during plasticization phase by HPLC analysis,Which could result in Sticky, the main reducing sugar is glucose and xylose. In the wholeprocess of impregnation plasticizing, the reaction of plasticizing temperature rise stage is themost intense, and the effect of phosphate on Chinese fir was more close to the effect on lignin;pyrolysis process is not proportional to impregnation concentration and impregnation ratio.When the concentration47%, impregnation and impregnation ratio3:1, weight loss rate is thehighest, the pyrolysis process and impregnation time proportional to the length of time, but theimpregnation time does not affect the whole pyrolysis process.The FACS were prepared from the Chinese fir Sawdust by H3P04.The method of factoranalysis and the orthogonal design were employed to investigate the preparation factors,whicheffect FAC on the pore structural characteristics and the adsorption properties of iodinenumber,Caramel decoloring rate and methylene blue were discussed and the optimum processconditions were determined as follow: concentration of phosphoric acid57%, impregnationratio of reactive agent to dried material2.2:1, temperature of kneading60C, Plasticizingtemperature150℃,activation temperature450C and activation time2.5h. the obtainedgranular activated carbon has Iodine number1073mg·g^-1, Caramel decoloring rate112.5%,methylene blue adsorption345mg·g^-1, BET1770m2·g^-1, developed in micropore.The FACS were prepared from the Chinese fir Sawdust by ZnCl₂activation.The method offactor analysis and the orthogonal design were employed to investigate the preparation factors,which effect FAC on the pore structural characteristics and the adsorption properties of iodinenumber and methylene blue were discussed and the optimum process conditions weredetermined as follow: concentration of ZnCl₂55%, Zinc scrap ratio2.8, Plasticizing temperature150C, Carbonization temperature350C,Carbonization time85min,activation temperature540C and activation time42min. Under optimum conditions, the obtained granular activatedcarbon has Iodine number1073mg·g^-1, methylene blue adsorption345mg·g^-1, BET1770m2·g^-1,Developed in micropore.Forming activated carbon prepared by H3P04compare with by ZnCl₂, the methylene blueand iodine adsorption value prepared by ZnCl₂are higher, the highest value is441mg·g^-1and 1588mg·g^-1, but the caramel is not higher and stabler than Phosphate method.