Physically (CO2) activated hydrochars from hickory and peanut hull: preparation, characterization, and sorption of methylene blue, lead, copper, and cadmium. Issue 30 (4th March 2016)

• Record Type: Journal Article
• Authors: Fang, June; Gao, Bin; Zimmerman, Andrew R.; Ro, Kyoung S.; Chen, Jianjun
• Is Part Of: RSC advances. Volume 6:Issue 30(2016)
• Page Start: 24906
• Page End: 24911
• Publication Date: 2016-03-04
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra01644h
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : CO2 activation of hydrochar resulted in improved physicochemical properties and greater sorption of various contaminants. Abstract : The effects of CO2 activation temperature (600–900 °C) and time (1 and 2 h) on the physicochemical and sorptive characteristics of hickory and peanut hull hydrochars were investigated. The extent of burn-off increased with increasing activation times and temperatures, and ranged from 34–54% and 28–50% for activated hydrochars (AHCs), respectively. The surface area and pore volume of the AHCs also increased with activation time and temperature and were much higher than those of their corresponding non-activated parent hydrochars. In general, the physical activation improved the ability of all AHCs to sorb methylene blue, lead (Pb 2+ ), copper (Cu 2+ ), and cadmium (Cd 2+ ) from aqueous solutions. AHCs created at 900 °C had the best sorption ability, and the highest sorption rate was usually observed in 900 °C 2 h AHCs. The sorption of methylene blue and the three heavy metals was strongly correlated with AHC surface area, suggesting that the adsorption occurred via site-specific interactions.