MCM-۴۱-NH₂/ThioP Mesoporous Silica Nanoparticles as a New Adsorbent for Mercury Ion Removal: Experimental and Theoretical Studies

Water pollution is a global environmental concern owing to its hazardous and harmful impacts on living systems. Mercury is considered as one of the most hazardous metals in the environment owing to its bioaccumulative property and consequent toxic impacts on human health. Industries that majorly cause water pollution by mercury ions are battery, oil refinery, electronic, and paint manufacturing industries. To minimize the impact of pollutants on ecosystems and human health, new materials that can purify water quickly and effectively are highly needed. Mesoporous silica nanoparticles with high surface areas, favorably interacting with other molecules via noncovalent interactions, have been utilized in pollutant removal. Among the members of these ordered mesoporous materials, MCM-۴۱ received the most attention and is the most studied material. So, to enhance the adsorption effectiveness of MCM-۴۱ for Hg²⁺, it needs to be functionalized with organic or inorganic groups. Here, a magnetic MCM-۴۱-NH₂ was functionalized by an inorganic material phosphortriamide (ThioP). Novel nanocomposite with formula MCM-۴۱-NH₂/ThioP contain a magnetic core characterized by TGA-DTA, FT-IR, XRD, and N₂ adsorption-desorption techniques. The adsorption capability of Hg²⁺ species on the hybrid sorbent MCM-۴۱-NH₂/ThioP, and the effect of several factors such as temperature, adsorbent dosage, initial mercury concentrations, pH, and existence of coexisting ions was systematically investigated. Further, the adsorption isotherm, kinetic, adsorption mechanism, and thermodynamic parameters of Hg²⁺ on the composite were thoroughly analyzed. Experimental technique and theoretical calculation were used to show adsorption mechanism and the interaction of Hg²⁺ molecules on the surface of adsorbent. The manufactured composite demonstrates an excellent adsorption performance for adsorption of Hg²⁺ ions with an exothermic, spontaneous, and chemical reaction. The presence of NH and ThioP groups is important for adsorption.

کلیدواژه ها:

Water treatment ، Mesoporous silica ، phosphor triamide ، Hg۲+ removal ، Theoretical studies