Composite And Carbonization Of Cellulose Aerogel, Adsorption Mechanism And Performance Study

Aerogel materials which prepared by cellulose have a number of merits such as non-toxic, biocompativility and so on. In this paper, cellulose aerogel was prepared by using linters cellulose as main body, the sol-gel and freeze-drying method. Carbon aerogel was obtained by the carbonization of cellulose aerogels. This method of preparation avoided complicated and expensive carbonation process. It had mild reactive conditions and was easy to control. The carbon aerogels were subsequently investigated by density, porosity, pyrolysis temperature, holding time, concentration of cellulose and oil absorbency. The adsorption property and mechanism of on carbon aerogel was discussed by effects of adsorption, adsorption isotherms, adsorption kinetics, thermodynamic examines. Cellulose/diatomite composite aerogel was prepared by using linters cellulose and diatomite. The cellulose/diatomite composite aerogels were subsequently investigated by density, porosity, and adsorption absorbency. The adsorption property and mechanism on cellulose/diatomite composite aerogel was discussed by effects of adsorption, adsorption isotherms, adsorption kinetics, thermodynamic examines.The results showed that2%-cellulose aerogel was pyrolyzed at350?for1h to generate the carbon aerogel which had the best performance with density of0.0308g·cm-3and porosity of95.90%. Carbon aerogel had excellent oil absorbency and stability of oil absorption circulation, and the highest oil absorption rate(peanut oil) was36.6312g·g-1. For the adsorption performance of methylene blue on carbon aerogel, alkaline environment availed adsorbing. Then Langmuir isotherm fitted the experimental results well and the maximal adsorbing capacity was124.0695mg·g-1. In addition, the adsorption could be explained by the mechanism of pseudo-second-order. Results suggested that the methylene blue adsorption on carbon aerogels was a spontaneous, physical and exothermic process. Cellulose/diatomite composite aerogel containing0.5%diatomite had the best performance with low density, high porosity and excellent adsorption preperty. Cellulose/diatomite composite aerogel had excellent oil absorbency and stability of oil absorption circulation, and the highest oil absorption rate(peanut oil) was18.3722g·g-1. For the adsorption performance of methylene blue on cellulose/diatomite composite aerogel, alkaline environment availed adsorbing. Then Langmuir isotherm fitted the experimental results well and the maximal adsorbing capacity was68.3995mg·g-1. In addition, the adsorption could be explained by the mechanism of pseudo-second-order. Results suggested that the methylene blue adsorption on cellulose/diatomite composite aerogels was a spontaneous, physical and exothermic process.