From Laboratory to Large-scale Manufacture of Anion Exchange Resin-supported Nano-hydrated Zirconium Oxide for As(V) Removal from Water Solutions

Abstract Nanotechnology has offered new chances for technical innovation in advanced water treatment. The nanocomposite HZO@D201 consisted of the strongly basic anion exchange resin D201 and the embedded hydrated zirconium oxide (HZO) nanoparticles (NPs). HZO@D201 integrated high reactivity of HZO NPs with the easy operation of D201, exhibiting great potential for efficient removal of arsenic, phosphate, and fluoride from (waste)water. However, the large-scale manufacture of HZO@D201 still faces challenges owing to the strong electrostatic repulsion between D201 and the NP precursors, i.e., [Zr4(OH)8(OH2)16]8+ tetramers. Herein, we reported a simple impregnation-precipitation method to prepare HZO@D201. The NP precursors were dissolved in ethanol and mainly existed in the form of electroneutral ion pair, thereby capable of diffusing inside D201 steadily. The subsequent precipitation allowed the in-situ growth of HZO NPs inside D201 to produce the nanocomposite HZO@D201-N. The pilot-scale manufacture was also conducted to produce 20 kg nanocomposite HZO@D201-N(P) once. The old synthetic method, i.e., evaporation of the aqueous solution to force NP precursors diffusing inside D201 followed by alkaline precipitation, was conducted to produce the nanocomposites in the laboratory (HZO@D201-O) and pilot-scale (HZO@D201-O(P)) as comparisons. The experimental results suggested a similar HZO loading (9-11.5%) among HZO@D201-O, HZO@D201-N, and HZO@D201-N(P), yet a much lower value (1.7%) for HZO@D201-O(P). Using As(V) as the representative pollutants, HZO@D201-O, HZO@D201-N, and HZO@D201-N(P) exhibited similar adsorption performance in both batch and column assays, dramatically superior to HZO@D201-O(P).