The adsorption and desorption behavior and mechanism research of cobalt, nickel and copper in nitrite-sulfuric acid system

In this paper, we studied the adsorption and desorption characteristics of cobalt, nickel, and copper in nitrite-sulfuric acid system, and their adsorption mechanism was also explored. The results showed that the adsorption capacity of cobalt and copper on the anion exchanger is 206 and 175 mg/g, respectively. However, the nickel adsorption capacity was very weak, exhibiting almost no adsorption. When the concentration of sodium nitrite was 1 mol/L, IRA-900 resin showed the best adsorption selectivity to cobalt. The FT-IR, UV absorption spectrometry, and XPS analysis results indicated that the adsorption mechanism of cobalt and copper could be attributed to the formation of anionic nitro-complexes in the solution, which could be exchanged with the anions on the resin to achieve the adsorption of metal ions. After a series of investigations, 1 mol/L sulfuric acid and ammonia were selected as desorption agents for cobalt and copper.

Automated summary

This paper investigated the adsorption and desorption characteristics of cobalt, nickel, and copper in a nitrite-sulfuric acid system and explored their adsorption mechanism. The results showed that cobalt and copper had a large adsorption capacity, while nickel had weak adsorption ability. The adsorption mechanism of cobalt and copper was confirmed to be the exchange between the anionic nitro-complexes in the solution and the anions on the resin. Sulfuric acid and ammonia were selected as effective desorption agents for cobalt and copper.