Adsorption-Based Synthesis of Environmentally Friendly Heterogeneous Chromium(III) Catalysts for Oxidation Reactions into Kaolinite, Saponite, and Their Amine-Modified Derivatives

Author(s)

Vieira, Carlos Alexandre ^[1] ; Ferreira, Breno F. ^[1] ; da Silva, Alexandre Fernando ^[1] ; Vicente, Miguel Angel ^[2] ; Trujillano, Raquel ^[2] ; Rives, Vicente ^[2] ; Ciuffi, Katia J. ^[1] ; Nassar, Eduardo J. ^[1] ; de Faria, Emerson H. ^[1]

Affiliation

^[1] Univ Franca, Ave Dr Armando Salles Oliveira, Parque Univ 201, BR-14404600 Sao Paulo - Brazil

^[2] Univ Salamanca, Dept Quim Inorgan, GIR QUESCATD, E-37008 Salamanca - Spain

• Document type: Journal article
• Source: ACS APPLIED NANO MATERIALS; v. 1, n. 8, p. 3867-3877, AUG 2018.
• Web of Science Citations: 0

Abstract

Batch experiments were used to evaluate the Brazilian Sao Simao kaolinite (Kao), the Spanish Yuncillos saponite (Sa), and their derivatives organofunctionalized with 3-aminopropyltriethoxysilane (Kao-APTES and Sap-APTES) as Cr(III) adsorbents in aqueous medium. Cr(III) concentration and interaction time affected Cr(III) adsorption, which depended strongly on surface charge. The adsorption capacities of Kao and Sap increased after functionalization. Cr(III) adsorption reached equilibrium within 30 min for kaolinite solids and within 120 min for saponite solids. Kinetics tests showed that Cr(III) adsorbent interactions did not follow a single model, and all the samples fitted the pseudo-second order model satisfactorily. Equilibrium studies showed that adsorption correctly fits the Langmuir model, but adsorption onto Kao and Sap-APTES fits the Freiindlich model better. Desorption experiments showed that Kao-APTES desorbed only 9.7% of Cr(III) cations under different stressing conditions as compared to 47.8% desorption in the case of Sap-APTES. The solids obtained after Cr(III) adsorption were used as heterogeneous catalysts for cis-cyclooctene oxidation reaction, being promising catalysts (conversion higher than 50%) and not showing leaching of Cr(III). (AU)

• FAPESP's process: 16/50322-2 - Materials with advanced technological and environmental applications
• Grantee: Katia Jorge Ciuffi Pires
• Support Opportunities: Regular Research Grants
• FAPESP's process: 16/01501-1 - Multifunctional catalysts for advanced oxidation processes employing biogenic matrices or clays
• Grantee: Katia Jorge Ciuffi Pires
• Support Opportunities: Regular Research Grants
• FAPESP's process: 12/08618-0 - Synthesis and characterization of zeolites obtained from natural clays for dye adsorption
• Grantee: Priscila Martins Pereira Rodarte
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 13/19523-3 - Functional Biohybrid materials based on layered and/or fibrous natural clays with multifaceted applications
• Grantee: Emerson Henrique de Faria
• Support Opportunities: Regular Research Grants