Schiff base-functionalized mesoporous silicas (MCM-41, HMS) as Pb(ii) adsorbents

Abstract

MCM-41@salen, HMS-C12@salen and HMS-C16@salen sorbents present high sorption capacities for Pb(ii) and are suitable materials for the removal of Pb(ii).

Kinetic Studies of Zn(II) Removal from Single and Binary Solutions by Synthetic Hydroxyapatite - Based Nanopowders

“…The pseudo-first-order kinetic model is based on the assumption that the rate of the adsorption process is proportional to the number of free active centers on the surface of the sorbent. This model is expressed in the form of the Lagergren equation: (2) where: k 1 is the rate constant of the pseudo-first-order sorption process (min -1 ) and Qe, Qt represent the equilibrium sorption capacity and the sorption capacity at time t (mg/g). The linear form of the Lagergren equation is: (3) where: k 1 is the rate constant of the pseudo-first-order sorption process (min -1 ) and Qe, Qt represent the equilibrium sorption capacity and the sorption capacity at time t (mg/g).…”

“…Heavy metal ions are known to be highly toxic and they are included in the category of toxic pollutants. Numerous industrial effluents loaded with heavy metals are discharged into the environment from industries such as: metal finishing processes, electroplating industry, mining industr y, batteries manufacture, inorganic chemical industry, textile industry, paintings, printing and photographic industries, energy industry and extractive hydrometallurgical processes [1][2][3][4][5].…”

PAMPS-graft-Ni3Si2O5(OH)4 multiwalled nanotubes as a novel nano-sorbent for the effective removal of Pb(ii) ions

“…Adsorption isotherms are widely used methods to evaluate the distribution of pollutants between the solid and liquid phase, which are benecial to understand the nature of adsorption. 45 In order to investigate the adsorption characteristic of PAMPS-g-Ni 3 Si 2 O 5 (OH) 4 NTs against Pb(II), two commonly used models, i.e. Langmuir and Freundlich models, were employed to describe the adsorption process.…”

Ultrafiltration Mixed Matrix Membranes Based on Mesoporous Silica (MCM-41, HMS)Embedded in Polysulfone

“…MCM-41 mesoporous silica has been prepared by using cetyltrimethylammonium bromide (CTAB) as structuredirecting agent and tetraethoxysilane (TEOS) as sol precursor to form silica mesopores, according to adapted literature procedures [27,29,30]. The reaction mixture was composed of 1.0 CTAB: 9.21 TEOS: 2.55 NaOH: 4857 H 2 O (molar ratios).…”

“…On the base of our previous achievements [27,28], mesoporous silicas of MCM-41 or HMS type were prepared via a surfactant-assembly Stöber sol-gel process and then incorporated into Psf casting solution to prepare novel composite membranes: M1 (Psf 12% + MCM-41), M2 (Psf 12% + HMS-C12), M3 (Psf 12% + HMS-C16) whose structures, morphologies and performances have been assessed by FTIR, TG-DSC, SEM-EDAX, contact angle measurements, and dead-end and cross-flow filtration experiments.…”