Research On Preparation And Adsorption Properties For VOC Of Activated Carbon Based On Xanthoceras Sorbifolia Processed Residues

Activated carbon is environment-friendly structure carbonaceous material with strong adsorption, large specific surface area and pore-rich, it is now widely used in the fields of agriculture, industry and environmental protection. Xanthoceras sorbifolia rich resources in northern China, can be used for biodiesel, however, Xanthoceras sorbifolia processed residues (Xanthoceras sorbifolia shell and Xanthoceras sorbifolia made oil residue) failed to get a better use. In this paper, two Xanthoceras sorbifolia processed residues as raw material, use zinc chloride as an activator, use nitrogen gas as a protective gas to prepare activated carbons, and further study of the adsorption capacity of two activated carbons for indoor VOC gases.In this paper, through the influence of zinc chloride concentration, impregnation ratio, carbonization temperature, carbonization time, activation temperature, activation time conditions on the adsorption properties of methylene blue(MB) and iodine(I2) to determine Xanthoceras sorbifolia shell activated carbon and Xanthoceras sorbifolia made oil residue activated carbon optimal parameters, and the use of SEM, adsorption and desorption isotherms, BET and BJH theory analysis on Xanthoceras sorbifolia shell activated carbon and Xanthoceras sorbifolia made oil residue activated carbon for microstructure. Investigated the effects of the adsorption temperature and the adsorption time for the activated carbon adsorption of VOC (formaldehyde, benzene, toluene, xylene, and ammonia gas), and further determines the VOC adsorption kinetics model.The main results of this paper are as follows:1. The effects of preparation conditions on Xanthoceras sorbifolia shell activated carbon adsorption properties of the text, the study showed:Xanthoceras sorbifolia shell activated carbon optimal preparation conditions were the zinc concentration of60%, impregnation ratio of2:1, carbonization temperature250℃, carbonization time3h, activation temperature600℃, activation time of60min, and at this moment the adsorptions of MB and12were368.69mg/g and1584.96mg/g.2. By characterizing the microstructure and related calculations Xanthoceras sorbifolia shell activated carbon analysis showed:Xanthoceras sorbifolia shell activated carbon adsorption-desorption isotherms meets Type I isotherms, and there is a wealth of micropores and mesoporous structure; BET specific surface area was1455.233m2/g, microporous about90%, mesoporous about10%.3. The effects of adsorption conditions on Xanthoceras sorbifolia shell activated carbon adsorption VOC, studies showed:Xanthoceras sorbifolia shell activated carbon adsorption capacity of VOC adsorption with increasing temperature decreases; Xanthoceras sorbifolia shell activated carbon maximum adsorption capacity for VOC (formaldehyde, benzene, toluene, xylene and ammonia gas) were366mg/g,1744mg/g,1964mg/g,1878mg/g and134.725mg/g; Xanthoceras sorbifolia shell activated carbon adsorption VOC compliance with Lagergren pseudo-second kinetic model.4. The effects of preparation conditions on Xanthoceras sorbifolia made oil residue activated carbon adsorption properties of the text, the study showed:Xanthoceras sorbifolia made oil residue activated carbon optimal preparation conditions were the zinc concentration of60%, impregnation ratio of2:1, carbonization temperature250℃, carbonization time3h, activation temperature600℃, activation time of60min, and at this moment the adsorptions of MB and12were258.425mg/g and1014.1mg/g.5. By characterizing the microstructure and related calculations Xanthoceras sorbifolia made oil residue activated carbon analysis showed:Xanthoceras sorbifolia made oil residue activated carbon adsorption-desorption isotherms meets Type I isotherms, and there is a wealth of micropores and mesoporous structure; BET specific surface area was676.250m2/g, microporous about80%, mesoporous about20%.6. The effects of adsorption conditions on Xanthoceras sorbifolia made oil residue activated carbon adsorption VOC, studies showed:Xanthoceras sorbifolia made oil residue activated carbon adsorption capacity of VOC adsorption with increasing temperature decreases; Xanthoceras sorbifolia made oil residue activated carbon maximum adsorption capacity for VOC (formaldehyde, benzene, toluene, xylene and ammonia gas) were173mg/g,1388mg/g,1642mg/g,1556mg/g and81.175mg/g; Xanthoceras sorbifolia made oil residue activated carbon adsorption VOC compliance with Lagergren pseudo-second kinetic model.7. Contrast on the analysis of two kinds of residue active carbon structure and adsorption performance differences, analysis showed that:Xanthoceras sorbifolia shell activated carbon has relatively larger BET surface area, and it’s average microporous size was smaller, but Xanthoceras sorbifolia made oil residue activated carbon mesoporous ratio higher; Xanthoceras sorbifolia shell activated carbon has a higher adsorption capacity of MB,12and VOC, but the advantages of macromolecular adsorption adsorbate is not obvious.