Novel ball-milled biochar-vermiculite nanocomposites effectively adsorb aqueous As(Ⅴ).
Ball milling was used to fabricate a nanocomposite of 20% hickory biochar (600 °C) and 80% expanded vermiculite (20%-BC/VE). This novel composite adsorbent had much higher removal of As(V) from aqueous solutions than ball-milled biochar and expanded vermiculite. Characterization of these adsorbents showed that the enhanced As(V) adsorption was ascribed to much larger surface area and pore volume (2-6 times), notable changes in crystallinity, activation of cations, and increased functional groups in the nanocomposite compared with the ball-milled products of their pristine counterparts. The As(V) adsorption process by the 20%-BC/VE fitted well with the pseudo-second-order kinetic model (R2= 0.990) and Langmuir isotherm model (R2= 0.989) with a maximum adsorption capacity of 20.1 mg g-1. The 20%-BC/VE best performed at pH about 6. The adsorption efficiency was not sensitive to the competition of NO3-, Cl-, SO42-, as well as the coexistence of humic acid. However, the adsorption capacity for As(V) was significantly reduced by coexisting with PO43-. The 20%-BC/VE composite can potentially serve as a superior low-cost adsorbent for As(V) removal in real-world applications.
['Li|Fang|F|', 'Wan|Yongshan|Y|', 'Chen|Jianjun|J|', 'Hu|Xin|X|', 'Tsang|Daniel C W|DCW|', 'Wang|Hailong|H|', 'Gao|Bin|B|']
D000327:Adsorption D000538:Aluminum Silicates D001152:Arsenicals D002606:Charcoal D007700:Kinetics D053761:Nanocomposites D014874:Water Pollutants, Chemical D018508:Water Purification
Ball milling Vermiculite Arsenic adsorption Biochar-based nanocomposites Wastewater treatment