Preparation And Adsorption Properties Of Activated Carbon From Sapindus

The activated carbon was prepared by using the Sapindus residue with H3PO4 as a activator. The preparation process was optimized by orthogonal experiments, the influences of the mass ratio of alkali to carbon, activation temperature and hold time toward the methylene blue and iodine adsorption on activated carbon were investigate. The structures and properties of the activated carbon were characterized by the nitrogen adsorption-desorption and SEM methods. Experiments of adsorption of phenol-contained waste water by activated carbon were carried out. Some important factors such as activated carbon quantity, adsorption temperature, initial concentration of phenol and pH value were studied. Results showed that the adsorption of methylene blue and iodine on activated carbon can reach 82 mg/g and 773 mg/g, respectively, at an impregnation ratio of 1:1, an activation temperature of 500℃ and a hold time of 60 min. Meanwhile, the produced activated carbon possesses a specific surface area (SBET=738 m2/g) and adsorption pore volume (V=0.6692 cm3/g) with an average pore size diameter of 3.6257 nm. The optimum condition of adsorption is neutral, low temperature is good for adsorption, but temperature had limited effects on adsorption. The Sapindus activated carbon showed good results on adsorption capacity to phenol.The activated carbon with super-high specific surface area was prepared from Sapindus residue through microwave carbonization and classic activation method with KOH and K2CO3 as the activator. By investigating the methylene blue adsorption on activated carbon, the orthogonal experiments were applied to determine the optimistic activation condition, including the mass ratio of alkali to carbon, the activation temperature and the hold time. The structures and properties of activated carbon were characterized by the nitrogen adsorption-desorption, XRD and FTIR methods. The experiments showed that the maximum adsorption value of methylene blue on activated carbon was 595 mg/g where the alkali to carbon mass ratio was 4:1; the activation temperature was 800℃ and the hold time was 30 min. In this condition, the produced activated carbon had a large specific surface area (SBET= 3597.4 m2/g) and a high adsorption pore volume (V= 1.8204 cm3/g) with average pore size diameter of 2.0241 nm.We can select the best optimal conditions for preparing super-high specific surface a rea of activated carbon to perform adsorption experiments of the analog Cr (VI) waste water. The aim is to explore adsorption capacity of the ultra-high surface area of activat ed carbon Cr (VI) under different experimental conditions. Moreover, the kinetics of Cr ( VI) adsorbed by activated carbon was studied.Through modification and optimization of the preparing process, this research presents a prepare method of the ordinary activated carbon and super-high specific surface area activated carbon from the Sapindus residue after Saponins and bio-diesel extraction, that expands the application scope of biomass activated carbon. It not only helps to save the coal resource, but also gives an appropriate way to deal the wasted Sapindus residue. With this high added value, resource saving and easy commercialized solution, this research possesses some certain economic, environmental and social benefits.