Use of waste ceramics in adsorption technologies

•Waste ceramics was found as perspective sorbent of toxic contaminants.•The adsorption of toxic ions by waste ceramics may be applicable in decontamination technologies.•Waste ceramics belongs to low-cost and environmentally friendly materials.•Waste ceramics saturated with toxic ions may be incorporated into a building material.

Waste brick dust (WBD) was tested as a potential sorbent of cationic and anionic contaminants, including radioactive residues. For adsorption experiments, model water solutions of highly toxic and/or ecologically harmful cations (Cd, Pb, Cs) and anions (As, Sb, Cr, U) were selected. The adsorption of Cd2 + and Pb2 + on WBD was most effective (> 95%) at a very low sorbent dosage (up to 6 g L− 1). In terms of anionic contaminants, UVI was adsorbed as cationic complex particles [(UO2)n(OH)2n − 1]+ almost quantitatively (> 95%) at a sorbent dosage of 3 g L− 1. The effective adsorption of AsV (> 90%) occurred at around a dosage of 15 g L− 1. The adsorption of Cs+, CrVI and AsIII on WBD was almost ineffective. Except for Cs+ and CrVI, all investigated ions were adsorbed according to the Langmuir isotherm model, at the theoretical adsorption capacities Qt ≈ approximately 0.1 mmol g− 1 for Cd2 +, Pb2 + and UVI, and approximately. 0.04 for AsV and AsIII. The leachability of toxic particles from saturated WBD was very low for selectively adsorbed particles (≈ 0.01-0.08% wt.) and their stability decreased in the order: Pb2 + ≈ Cd2 + > UVI > AsV > AsIII ≫ Cs+ ≫ CrVI. The approximate consumption of WBD per gram of toxic element was found to be about ≈ 60 g for Pb2 + and UVI, ≈ 100 g for Cd2 + and > 400 g for AsV.