Direct Calorimetric Measurement of Enthalpy of Adsorption of Carbon Dioxide on CD-MOF-2, a Green Metal-Organic Framework

Autor(es)

Wu, Di ^{[1, 2]} ; Gassensmith, Jeremiah J. ^[3] ; Gouvea, Douglas ^{[1, 2, 4]} ; Ushakov, Sergey ^{[1, 2]} ; Stoddart, J. Fraser ^[3] ; Navrotsky, Alexandra ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Univ Calif Davis, NEAT ORU, Davis, CA 95616 - USA

^[2] Univ Calif Davis, Peter A Rock Thermochem Lab, Davis, CA 95616 - USA

^[3] Northwestern Univ, Dept Chem, Ctr Chem Integrated Syst, Evanston, IL 60208 - USA

^[4] Univ Sao Paulo, Escola Politecn, Dept Met & Mat Engn, BR-05508900 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of the American Chemical Society; v. 135, n. 18, p. 6790-6793, MAY 8 2013.
• Citações Web of Science: 73

Resumo

The enthalpy of adsorption of CO2 on an environmentally friendly metal-organic framework, CD-MOF-2, has been determined directly for the first time using adsorption calorimetry at 25 degrees C. This calorimetric methodology provides a much more accurate and model-independent measurement of adsorption enthalpy than that obtained by calculation from the adsorption isotherms, especially for systems showing complex and strongly exothermic adsorption behavior. The differential enthalpy of CO2 adsorption shows enthalpy values in line with chemisorption behavior. At near-zero coverage, an irreversible binding event with an enthalpy of -113.5 kJ/mol CO2 is observed, which is followed by a reversible -65.4 kJ/mol binding event. These enthalpies are assigned to adsorption on more and less reactive hydroxyl groups, respectively. Further, a second plateau shows an enthalpy of -40.1 kJ/mol and is indicative of physisorbed CO2. The calorimetric data confirm the presence of at least two energetically distinct binding sites for chemisorbed CO2 on CD-MOF-2. (AU)

• Processo FAPESP: 11/02080-6 - Adsorção de CO2 na superfície de nanopartículas de ZnO e sua relação com a entalpia de superfície e estabilidade de tamanho
• Beneficiário: Douglas Gouvêa
• Modalidade de apoio: Bolsas no Exterior - Pesquisa