Removal of hexavalent chromium from electroplating wastewater by ammoniated distilled grain-based adsorbent

To remove hexavalent chromium (Cr(Ⅵ)) from electroplating wastewater, the ammoniated distilled grain-based adsorbent was prepared using the fermentation residue as the raw material by means of ammonia modification. The composition and structure of the adsorbent was analyzed and characterized by FTIR, EDS, BET and SEM, and its effect on Cr(Ⅵ) adsorption was studied under different pH and adsorbent dosage. The results showed that the amounts of amino groups were introduced into the surface of the ammoniated distilled grain-based adsorbent, and the contents of nitrogen element reached 4.40%. At equilibrium pH is 2.7, the saturated adsorption capacity of Cr(Ⅵ) reached maximum value 150.45 mg/g, and the average adsorption rate reached 1 791.90 mg/(g·h). In addition, the regeneration performance of the adsorbent was evaluated. After five regeneration cycles, the adsorption performance of the adsorbent to Cr(Ⅵ) reached 98.44 mg/g, and the adsorption performance loss rate was 19.60%.