Preparation Of Activated Carbon From Waste Mushroom Culture Medium And Study Of Its Adsorption And Regeneration

In recent years, waste of mushroom medium caused a great pressure to the environment. Buried or burned was the main treatment, which polluted the environment and caused waste of resources. We found the abandoned mushroom culture medium was composed of wood. Waste mushroom culture medium was rich in cellulose and hemicellulose, so it could be prepared. Because of the huge specific surface area, developed pore structure and stable chemical properties, the activated carbons were applied to the field of adsorption. With the development of our country industry, wastewater containing Cr (VI) caused a serious threat to people’s life. Activated carbon become one of the most commonly treatment method, because of its advantages of safety and simple operation.This study adopted the abandoned mushroom medium as the raw material, KOH as activator, preparaed of activated carbon by muffle furnace and microwave. The optimal process condition was determined by the single factor experiment, and analysis of the activated carbon. Compared two kinds of preparation of the activated carbon on the adsorption of Cr (VI) solution process. The best adsorption conditions was determined. At the same time, the study has carried on the microwave regeneration to the activated carbon and the regeneration performance was evaluated. The results show that:(1) By considering the yield, the iodine number, the BET surface area and the phenol adsorption, the optimum conditions were determined as follow: reagent ratio of 3:1, activation temperature 850 ℃, activation time 60 min, under this condition, the yield of activated carbon was 60.1%, the iodine adsorption value was 1040.21 mg/g, specific surface area was 1177.4 m2/g. Optimum conditions for microwave preparation:carbon ratio of 3:1, the irradiation time 15 min, power 800 w, under this condition, the yield of activated carbon was 62.9%, the iodine adsorption value was 1252.21 mg/g, specific surface area was 1700.0 ml/g.(2) Activated carbon samples from each MAC-K and WAC-K 0.1 g adsorpted 100 ml of initial concentration of 100 mg/L Cr (VI) solution. When the solution pH value was 2, temperature was 45 ℃, 180 min they could reach adsorption equilibrium, and the adsorption effect was best, adsorption capacity were 85.29 mg/g,92.27 mg/g, removal rate was 85.29%,92.27% respectively. The whole adsorption process conforms to the quasi secondary adsorption dynamics equation, the chemical adsorption. Langmuir adsorption isotherm model could describe the adsorption process.(3) The activated carbon of microwave regeneration had best adsorption performance when power of 600 w, time of 5 min. The adsorption quantity was still the initial adsorption quantity 71%-75% after five adsorption/recycling times. The carbon loss was 6.6%.