title: Adsorption of Lead Ions from Aqueous Phase on Mesoporous Silica with P-Containing Pendant Groups.
abstract: Mesoporous silica materials with hydroxyphosphatoethyl pendant groups (POH-MS) were obtained by a two-step process: (1) block copolymer Pluronic P123-templated synthesis of mesoporous silica with diethylphosphatoethyl groups (DP-MS) by co-condensation of diethylphosphatoethyl triethoxysilane (DPTS) and tetraethylorthosilicate (TEOS) under acidic conditions and (2) conversion of diethylphosphatoethyl into hydroxyphosphatoethyl groups upon suitable treatment with concentrated hydrochloric acid. The DP-MS samples obtained by using up to 20% of DPTS featured hexagonally ordered mesopores, narrow pore size distribution and high specific surface area. Conversion of DP-MS to mesoporous silica with hydroxyphosphatoethyl groups (POH-MS) resulted in the enlargement of the specific surface area, total porosity, and microporosity. High affinity of hydroxyphosphatoethyl groups toward lead ions (Pb(2+)) makes the POH-MS materials attractive sorbents for lead ions, which is reflected by high lead uptake reaching 272 mg of Pb(2+) per gram of POH-MS. This study shows that the simple and effective co-condensation strategy assures high loading of P-containing groups showing high affinity toward lead ions, which is of great importance for removal of highly toxic lead ions from contaminated water.
authors.affiliation: Department of Chemistry and Biochemistry, Kent State University , Kent, Ohio 44242, United States.
authors.forename: Chamila
authors.initials: C
authors.lastname: Gunathilake
authors.affiliation: Department of Chemistry and Biochemistry, Kent State University , Kent, Ohio 44242, United States.
authors.forename: Murthi S
authors.initials: MS
authors.lastname: Kadanapitiye
authors.affiliation: Chuiko Institute of Surface Chemistry NAS of Ukraine , 17, General Naumov Street, Kyiv, 03164, Ukraine.
authors.forename: Oksana
authors.initials: O
authors.lastname: Dudarko
authors.affiliation: Department of Chemistry and Biochemistry, Kent State University , Kent, Ohio 44242, United States.
authors.forename: Songping D
authors.initials: SD
authors.lastname: Huang
authors.affiliation: Department of Chemistry and Biochemistry, Kent State University , Kent, Ohio 44242, United States.
authors.forename: Mietek
authors.initials: M
authors.lastname: Jaroniec
keywords: adsorption; diethylphosphatoethyl triethoxysilane; lead; mesoporous organosilica