Study On Removal Of Zn²⁺ From The Drinking Water Treated By SPM

The hygiene and safety of drinking water affect human's life and health directly. Water pollution, weakness of traditional drinking water treatment, and disinfection by products (DBP) of chlorination, all of the above factors result in the difficulty to ensure the quality of water. As a new kind of water purified material, SPM (Special Powder Material) could be used in drinking water's advanced treatment. However, concentration of Zn2+ would be high sometimes after treated by SPM. A variety of adsorbent materials were researched on the removal of Zn2+. Medical stone, tourmaline, molecular sieve were selected to do static test so as to research the different relationships of adsorption effect with adsorption time, temperature, dosage, and pH value. The adsorption efficacy was described as follows: tourmaline 1#>molecular sieve>tourmaline 2#>medical stone. Tourmaline 1# performed best when dosage=0.2 g; temperature=30℃; adsorption time=1.5 h and pH=6.0-9.0. Furthermore, kinetics and thermodynamics property of Zn2+ adsorption were also investigated. Pseudo second order adsorption kinetics and Freundlich adsorption isotherm were adopted to describe the adsorption. Influence on penetration curve from bed height, velocity and concentration were examined in the dynamic test. Penetration time would be shortened with reduction of bed height, increasing of velocity or concentration. Run time of tourmaline 1# was longer than tourmaline 2# under the same condition. Finally, tourmaline 1# was coupled with SPM. It was effective at different volume ratio and velocity. The work above provides a solution to popularize SPM.