Adsorption and regeneration of Volatile Organic Compounds(VOCs) on coal-based activated carbon by ferric nitrate modification
2021, 23 (3):
In this work, heishan coal was used to prepare a series of activated carbon samples (ACs) l via a vapor depositition method. The effects of the weight ratio (Fe(NO3)3:coal ) on the physicochemical properties of the activated carbon were systematically investigated, and the ACS samples were detected by N2 adsorption-desorption, SEM, XRD, Raman and FTIR. Furthermore, the adsorption properties for ethyl acetate were tested. The results indicated that as the ratio increasing from 1:8 to 1:2, the specific surface area, total pore volume and micropore volume first increase and then decrease，the specific surface area increased from 560.86 m2/g to 685.90 m2/g and then decreased to 299.56m2/g. The total pore volume and micropore volume increased from 0.29cm3/g, 0.17cm3/g to 0.30cm3/g, 0.22cm3/g, and then decreased to 0.16cm3/g and 0.10cm3/g, respectively. The optimized ratio is ~. in the activation process, The iron ions would be infiltrated into the activated carbon could significantly promote the development of pore structure, especially the pores with pore size between 2.5-3nm, which enhance the adsorption capacity of ethyl acetate. It is worth noting thatthe ACs had the largest specific surface area and total pore volume of 685.90 m2/g and 0.30 cm3/g under the optimized activation (950oC, 20 vol.% CO2 ,the ratio is 1:5), the maximum adsorption capacity of ethyl acetate was 962.62mg/g, and after 7 times of repeated thermal regeneration experiments, the saturated adsorption capacity was still above 90%.