Preparation And Adsorption Properties Of Camellia Seed Cake Based Activated Carbon

According to statistics, there are about 55 million hectares of Camellia oleifera in China and more than 60 million tons of Camellia oleifera seed are producted annual. The by-product which are left after oil extraction of is about 500,000 tons per year.The Camellia oleifera have high economic value, but the economic benefits are very low. Against to the utilization of the Camellia oleifera, we choose cake of camellia oleifera seed as the raw material of making actived carbon.A study on using cake of camellia oleifera seed which saponins have been taken out as raw materials to produce porous carbon materials was conducted, by controlling the conditions of single-factor (activator, activator ratio,activation temperature, activation time and particle size of raw materials).The adsorption value of iodine standard solution, methylene blue solution and the vitamin B12 solution was determinated. Considering the experimental conditions on the carbon yield and the law of adsorption properties, the study have explored the optimal process conditions of preparation carbon materials by different activator. Experimental results:select ZnCl2 as the activator,the best condition is the raw material particle size 20 to 60 mesh, activator ratio 1.5,activation temperature 700℃,activation time 60 min. Select Fe(NO3)3 as the activator,the best condition is the raw material particle size 60 to 200 mesh, activator ratio 0.2,activation temperature 700℃,activation time 90 min.The Infrared spectra show two carbon material surface functional groups is similar. The pore structure of ZnCl2 activated carbon is regular. The carbon mateial presented a BET surface area of 1177.96 m2/g, pore volume of 0.76 cm3/g and average pore size 2.58 nm. The pore structure of Fe(NO3)3 activated carbon is irregular. The carbon material presented a BET surface area of 532.69 m2/g, pore volume of 0.33 cm3/g and average pore size 2.45 nm.Studies have carried out for adsorption wasterwater containing methyl orange and vitamin B12 using the actived carbons activated by ZnCl2, and the effects of shaking time, the activated carbon dosage, pH, temperature and the initial concentration are well studied to abtain the optimal process parameters. The thermodynamics parameters of the adsorption process are calculated by the van't Hoff equation, the higher the temperature is, the more adsorption capability the carbon can achieve.We use Langmuir and Freundlich isotherms at different temperature to analyze the equilibrium data, and find out that the Langmuir isotherms have a higher correlation.The experimental results were analyzed by pseudo-second-order kinetics model, correlation is higher than 0.999. Both of the adsorption rate of methyl orange and vitamin B12 are controlled by fim diffusion.