Adsorption of lead(II), cadmium(II) and dysprosium(III) from aqueous solutions using mesoporous silica modified with phosphonic acid groups

Adsorption Analyses of Phenol from Aqueous Solutions Using Magadiite Modified with Organo-Functional Groups: Kinetic and Equilibrium Studies

“…Researchers reported that the layered silicate is not only rich in natural reserves, but also has a large specific surface area and excellent pollutant adsorption capacity; therefore, it is considered one of the most promising substances for use as an adsorbent [19]. The use of different types and compositions of organic surfactants to modify layered silicates to enhance the adsorption capacity of organic pollutants in water is one of the hotspots in environmental remediation and wastewater treatment [20,21]. Later, researchers reported on a layered silicate of magadiite which has high purity, ion exchange capacity, and possesses good thermal as well as chemical stability [22].…”

Catalytic Conversion of Xylose and Xylan into Furfural Over Cr3+/P-SBA-15 Catalyst Derived from Spent Adsorbent

“…7−9 It was generally accepted that the adsorption capacity of SBA-15 composites for metal ions can be enhanced by grafting Brønsted acidic functional group on its surface due to the strong complexing ability of acidic functional groups with metal ions. 10,11 In our previous work, 4 Cr 3+ was proven to be a particularly effective Lewis acid site that helped promote the formation of furfural from xylose. Referring to the above background, an interesting strategy was put forward that if Brønsted acidic SBA-15 derived adsorbents adsorbed with toxic Cr 3+ ions can be used as acidic bifunctional heterogeneous catalysts in the catalytic formation of furfural, it would be of great significance for the secondary utilization of spent adsorbents.…”

“…Specifically, xylose was first subjected to isomerization under the catalysis of a Lewis acid, and then the formed xylulose was dehydrated in the presence of Brønsted acid to form furfural (Scheme ). , SBA-15 is a 2D hexagonal ordered mesoporous silica material with tunable pores in 4–11 nm, which not only has the relatively large pore size, desired hydrothermal stability, and adsorption capacity, but also achieves adsorption equilibrium in a short time. , Therefore, in recent years, SBA-15 and its derivatives have been frequently employed as impactful adsorbents for the removal of heavy metal ions (Cu 2+ , Zn 2+ , Cr 3+ , Cr 6+ , Ni 2+ , Cd 2+ , Mn 2+ , Pb 2+ , As 5+ ) from wastewater. − It was generally accepted that the adsorption capacity of SBA-15 composites for metal ions can be enhanced by grafting Brønsted acidic functional group on its surface due to the strong complexing ability of acidic functional groups with metal ions. , In our previous work, Cr 3+ was proven to be a particularly effective Lewis acid site that helped promote the formation of furfural from xylose. Referring to the above background, an interesting strategy was put forward that if Brønsted acidic SBA-15 derived adsorbents adsorbed with toxic Cr 3+ ions can be used as acidic bifunctional heterogeneous catalysts in the catalytic formation of furfural, it would be of great significance for the secondary utilization of spent adsorbents.…”

Dehydration of Xylose and Xylan to Furfural using P‐Zr‐SBA‐15 Catalyst in Aqueous or Biphasic System

“…Its skeleton interior and surface can be modified by introducing active components such as metals, metal oxides, and acid functional groups. [12][13][14] The acidity of molecular sieves and the number and strength of active sites significantly impact catalytic performance. The catalytic activity and selectivity of molecular sieves can be improved by increasing the acidity of molecular sieves.…”

“…On the other hand, SBA‐15 pure silicon molecular sieve has no active groups on its surface. Its skeleton interior and surface can be modified by introducing active components such as metals, metal oxides, and acid functional groups [12–14] . The acidity of molecular sieves and the number and strength of active sites significantly impact catalytic performance.…”