Adsorption of Acid Modified Distillers' Grains for heavy metal ions Pb(II) and Cr(III)

摘要

Modification of distillers' grains by hydrochloric acid, phosphoric acid, sulfuric acid and nitric acid, respectively, was carried out in order to enhance their adsorption capacities of heavy metal ions. Fourier transform infrared (FTIR) spectroscopic analysis reveals modified distillers' grains have rich hydroxyl and amides. SEM images of distillers' grains' surface show that modified distillers' grains particles have larger surface area and loose structure feature than the raw distillers' grains (RDG). Modified distillers' grains by nitric acid exhibited higher adsorption capacities for Pb(II) and Cr(III) than RDG. The adsorption capacities of nitric acid treated distillers' grains and RDG for Pb(II) were 20.35 and 15.69 mg g~(-1), respectively. A simple modification of distillers' grains with nitric acid has improved adsorption ability of distillers' grains particles for heavy metal ions.