Unusual Adsorption Properties of Microporous Titanosilicate ETS-10 toward Heavy Metal Lead

Abstract

Microporous titanosilicate ETS-10 was synthesized by using TiF4 as the Ti source and characterized by using X-ray diffraction, Fourier transform infrared and Raman spectroscopies, and nitrogen adsorption. The adsorption properties of heavy metal ion Pb2+ on the ETS-10 sample were studied by measuring the adsorption kinetics and equilibria using a batch-type method. It has been observed that the adsorption rate of Pb2+ on ETS-10 is extremely rapid: less than 5 s is required to attain maximum adsorption capacity in a 10 mmol/L solution with a batch factor of 200 mL/g. The kinetic data can be fitted very well by a pseudo-second-order model, whereas the equilibrium data are better fitted to the Langmuir isotherm than to the Freundlich isotherm. The maximum adsorption capacity of Pb2+ on ETS-10 as predicted by the Langmuir equation is 1.12 mmol/g. This is the highest adsorption capacity of Pb2+ on zeolites that has been observed so far.

Rapid and Effective Adsorption of Lead Ions on Fine Poly(phenylenediamine) Microparticles

“…[32] A comparison of Pb 2 + adsorption onto the microparticles and other sorbents: As discussed above, the highest Pb 2 + adsorption capacities are found to be 253.2 and 242.7 mg g ) [33] and other better absorbents, such as hydrated ironA C H T U N G T R E N N U N G (iii)-oxide-grafted poly(acrylamide) (211.4 mg g À1 ), [7] modified microporous poly(2-hydroxyethyl methacrylate) (174.2 mg g À1 ), [21] dithizone-anchored poly(2-hydroxyethyl methacrylate) microbeads (155.2 mg g À1 ), [22] and modified poly(vinylbutyral) microbeads (86.2 mg g À1 ). [19] In fact, the Pb 2 + ion adsorption capacity on PpPD is close to that of microporous titanosilicate (231.8 mg g À1 ) [13] and hybrid macroporous modified silica (256.7 mg g À1 ). [14] The adsorption rate of Pb 2 + ions onto PpPD and PmPD microparticles is much faster than that onto oxidized nanoporous activated carbon, [33] ironA C H T U N G T R E N N U N G (iii)-oxide-grafted poly(acrylamide), [7] and poly(vinylbutyral) microbeads.…”

“…In recent years, adsorption has been shown to be an effective and economically feasible alternative method for removal of heavy-metal ions. [6][7][8] Nonspecific sorbents such as activated carbon, [9,10] metal oxides, [11,12] silica, [13][14][15] ion-exchange resins, and biosorbents [16] have been used. Specific sorbents have been proposed, consisting of a ligand that can specifically interact with the metal ions, and a carrier matrix that may be an inorganic material (e.g., silica) [14,15,17] or polymers (such as polyA C H T U N G T R E N N U N G (styrene), poly(methacrylate), or poly(vinylbutyral)).…”

Macrocyclic Amine‐Linked Oligocarbazole Hollow Microspheres: Facile Synthesis and Efficient Lead Sorbents

“…For this case, a mechanism similar to that of exchange interactions published before [ 15 ] is proposed. Note that the Pb(II) sorption capacities of our OCB sorbents compare very favorably to those values (Table S2, Supporting Information) reported for Zn 2 GeO 4 -ethylenediamine hybrid nanoribbons (74.6 mg g −1 ), [ 2 ] sulfonated polyphenyldiamine (91.8 mg g −1 ), [ 16 ] longan shell (52.1 mg g −1 ), [ 17 ] polyvinylbutyral microbeads (86.2 mg g −1 ), [ 18 ] polysulfoaminoanthraquinone nanoparticles (89.6 mg g −1 ), [ 19 ] diethylenetriamine-bacterial cellulose (22 mg g −1 ), [ 20 ] meranti sawdust (34.3 mg g −1 ), [ 21 ] thiol-functionalized ceramic hybrids (22.4 mg g −1 ), [ 22 ] activated carbon (4.77 mg g −1 ), [ 23 ] titanosilicate ETS-10 (56.3 mg g −1 ), [ 24 ] and cellulose-chitosan hydrogels (28.1 mg g −1 ). [ 25 ] More importantly, the production of OCB microspheres is a low-cost and environmentally friendly process owing to the cheap starting materials and simple one-step aqueous synthesis.…”

ETS‑10 Modified with CuxO Nanoparticles and Their Application for the Conversion of CO2 and Water into Oxygenates

“…The small peak in 640 cm -1 corresponds to the degenerated Eg active mode of anatase TiO 2 , probably in a very small concentration to be detected by XRD. 63,64 After the Cu 2 O and CuO nanoparticles decoration, the maximum of the peak is displaced by 7 cm -1 to lower frequencies, while the low frequency side of the peak presents a 16 cm -1 difference between the curves corresponding to ETS-10 and decorated ETS-10 (see Figure 3) corresponding to an enlargement of the peaks. These effects can be associated with the interaction between the Cu x O nanoparticles and Ti-O-Ti wires in the framework, promoting local electronic change in the ETS-10 titanate chains.…”