Design and synthesis of hydrophobic mixed organogels with complementary hydrogen-bond donor–acceptor sites: removal of heavy metal ions Hg²⁺, Cd²⁺ and Pb²⁺ from aqueous solution

Abstract

The hydrophobic organogel G8GE with metallogel formation and shape forming ability is used in the removal of Hg(ii), Cd(ii) and Pb(ii) from contaminated water with low cost-effected reusability.

A Siderophore Mimicking Gelation Component for Capturing and Self-Separation of Fe(III) from an Aqueous Solution of Mixture of Metal Ions

“…However, with the synthesized gelation component CBTC , a suitable solvent composition could not be found to get it self-assembled into a stable gel. However, it has been observed and reported that adding other molecules of similar symmetry and providing complementary hydrogen bond donor–acceptor sites , could induce gelation in the whole system . Among the available library of molecules, trimesic acid with a similar symmetrical structure with the probability of π–π stacking among aromatic rings and provision of complementary hydrogen bond donor–acceptor sites is selected for further investigation to use as the second gelation component.…”

“…In our previous reports, , the concept of complementary hydrogen bond donor–acceptor sites was introduced, which accounts for the strengthening and improved properties of the gels. The presence of complementary hydrogen bond donor–acceptor sites in trimesic acid makes it an ideal candidate for use as a second component along with the gelation component CBTC to induce gel formation.…”

“…49−51 Recently, we reported tricarboxamides-based organogels that can capture heavy metal ions such as Hg 2+ , Pb 2+ , and Cd 2+ . 43 In biological systems, siderophores are known for their ability to chelate with Fe(III). This encouraged us to fabricate a similar system that can form a gel and act as a siderophore-mimicking agent by scavenging iron from a mixture of other ions.…”

“…Its capability of forming a gel has been checked separately with Fe 3+ and other transition metal ions but without success for the fabrication of any gel. In our continuous efforts to develop various LMWGs and metallogels, we have introduced the concept of complementary hydrogen bond donor–acceptor systems, which can form hydrogen bonds with the gelation components or gelator molecule, inducing the gelation and improving the gel strength. , Taking a cue from such an observation, we have introduced a second component, trimesic acid, along with the gelation component CBTC , having complementary hydrogen bond donor–acceptor sites. The gelation component CBTC , along with trimesic acid, has been checked to form a gel with various 3d metal ions, but it forms a gel spontaneously and exclusively with Fe 3+ among them.…”

Remediation of Dyes Using Supramolecular Material Derived from Carbohydrate Based π-Gelator Using the Bottom-Up Assembly Approach

“…Recently, Sureshan and co-workers have demonstrated the use of a carbohydrate-based gel system in oil spill remediation and ion sequestration, which is considered a major environmental concern. − Soft material fabricated from 1,3:2,4-dibenzyldene-D-sorbitol (DBS) displayed stimuli-responsive behavior with respect to pH and UV irradiation in the presence of diphenyl iodonium nitrate forming photo-patterned multidomain gels . In addition, acetal-protected D-sorbitol displays robust self-assembly behavior, which is greatly influenced by the solvent used. − In continuation of our ongoing research in the field of supramolecular chemistry, we have designed a gelator from D-sorbitol, an FDA-approved molecule bearing the E number 420 displaying applications in food, cosmetics, and pharmaceutical industries, and pyrene-1-carboxaldehyde.…”