Plasma modification of ZnMgAl-LDHs for adsorption property improvement

Dielectric barrier discharge (DBD) non-thermal plasma was applied for ZnMgAl-LDHs modification to improve the adsorption property of methyl orange (MO). ZnMgAl-LDHs were prepared by co-precipitation method, and characterized via XRD, EDS, BET, SEM and FT-IR. Effects of plasma modification time, initial pH, initial MO concentration and adsorbent dosage on adsorption property of samples were investigated. The results showed that plasma modification led to the increase of specific surface area, pore volume and average pore size, as well as good dispersion. ZnMgAl-LDHs treated by combination of plasma modification for 30 min with calcination at 450 degrees C for 5 h exhibited high adsorption capacity of 1327 mg/g, much higher than without plasma modification. The equilibrium data for the adsorption of MO on adsorbents could be well fitted by the Pseudo-second-order equation and Langmuir equation. Plasma modification could be a potential and effective way for adsorption property improvement. (C) 2017 Taiwan Institute of Chemical Engineers.