Blending Preparation Of High Surface Area Of ​​coal-based Activated Carbon

HSAAC(high surface area activated carbon) is widely used in fuel gas storage, gas separation, catalysis and various chemical processes, because of having more micro-porous and high absorption capacity. As a major coal province of Heilongjiang, rich coal resources for the development of activated carbon industry has provided favorable conditions.In this disquisition, HSAAC were prepared by KOH activation and N₂ protection with orthogonal design from three typical coals of Heilongjiang which were Qitaihe coal, Yilan coal and Jixi coal. The optimum technics conditions were determined by adsorption value of I2. The results was indicated that,the activated carbon of which the absorption value of I2 and BET surface area respectively reached up to 1946 mg·g^-1 and 1721 m2·g^-1 above, was prepared by Qitaihe anthracite pretreated under the experimental conditions of activated temperature of 850℃, activated time of 120min and ratio of alkali/carbon of 5/1.Blending coal study of Qitaihe and Yilan coal was also done at the same time, The results showed that the best experiment condition was the two type of coals as 1/1 ratio mixture, ratio of alkali/carbon of 6/1, activated temperature of 850℃, activated time of 120min. The main influence factors in order were the ratio of coal, ratio of alkali/carbon, activated temperature and activated time. On this condition the absorption value of I₂ and BET surface area respectively reached up to 1973mg·g^-1 and 1735 m²·g^-1.The results also show the reaction rate of burn-off B is first-order reaction used KOH in 800⁹50℃. According to Arrhenius equation, it is calculated that the apparent activation energy of carbonization-activation reaction is 101.4032 kJ·mol^-1, and the pre-exponential factor is 3.1382×10⁴. The adsorption equilibrium of phenol onto activated carbon based adsorbents can be described in terms of the Freundlich isotherm. Phenol adsorption capacity onto activated carbon decreases with increasing temperature, the adsorption parameters of thermodynamics△H are -9.6108 kJ·mol^-1,△S are -20.0541 J·mol^-1·K^-1,△G are negative. The kinetics of phenol adsorbed respectively onto coal based superfine composite adsorbents fit the second order kinetic model. the velocity constant k2 is 1.9515×10^-2 g·mg^-1·min^-1.