Preparation and Evaluation of a Ce(IV)-La(II) binary hydroxide Adsorbent as Recovery of Waste Ceria Powder From Glass Polishing Process For Effective Arsenic Removal
In this paper Ce(IV)-La(III) binary hydroxide adsorbent, herein referred to as CLH adsorbent, which is a recovery of waste ceria powder from glass polishing process, is used as a novel adsorbent for removing inorganic arsenic (As) from water. The CLH adsorbent is prepared using a combined acid and heating treatment method, which involves refluxing the waste ceria powder in 2 M H2SO4, adding NaOH for complete precipitation, filtering, and drying at 80–90°C. The adsorption of As onto CLH is studied as a function of adsorbent dose, contact time, and pH. Within the range of tested (pH 4–11), the optimal pH for As(V) and As(III) adsorption is 4 and 8, and close to 100 % removal can be achieved at adsorbent dose of 2.0 g L–1, fixed ionic strength (0.01 M NaNO3), and room temperature (25±1°C) for an initial As concentration of 10 mg L–1 within 6 h irrespective of the initial pH, and the time required to reach pseudoequilibrates changes with the initial pH. The CLH adsorbent appears to be an efficient and cost-effective material for both As(III) and As(V) removal. The experiment provides also a feasible and promising way to use waste as a material for the treatment of other wastes or contaminants from the point of recycling.