Development of chemical processes following principles adopted by green chemistry: reduction and conversion of CO2 using Mn(I) compounds

• Grant number: 11/06244-3
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: July 01, 2011
• End date: February 28, 2014
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Rose Maria Carlos
• Grantee: Mariana Romano Camilo Casale
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

The petrochemical industry, through the development of many chemical processes has made great contributions for humanity, but at the same time it damages the environment by releasing large amounts of CO2 in the atmosphere and significant amounts of toxic wastes and pollutants produced in the chemical industry. From an economic and environmental perspective there is an urgent demand for methods which promote the capture and conversion of released CO2 and by chemical processes using "greener" and more efficient methods, for example, methods which employ clean oxidants such as H2O2 and O2 and a recyclable catalyst "preferentially" and that operate using renewable energy sources like solar energy. Such methods seek to fulfill the twelve principles of green chemistry proposed by Anastas and Warner (Anastas, PT, Warner, JC "Green Chemistry: Theory and Practice", Oxford University Press: Oxford, 1998). These requirements were successfully achieved by our research group with the development of manganese (Mn) complex capable of cleaving the water molecule with generation of O2(g) and H2(g) after absorbing visible light. These results motivated us to exploit the enormous potential of these complexes for photocatalytic production of fuels and/or chemicals of interest following the principles of a healthy environment with chemical processes. In this project, we aim to evaluate the photochemical properties of manganese complexes developed in our laboratory investigating the essential chemical process for the chemical industry: the reduction and conversion of CO2 molecule. In this context, solutions of the manganese complexes were prepared in the presence and absence of CO2, and In this context, solutions of the manganese complexes were prepared in the presence and absence of CO 2 and these solutions were irradiated with visible light and then the products generated were identified and quantified using spectroscopic (UV-Vis, IR, 1H and 13C NMR) and electrochemical techniques (cyclic voltammetry and spectroelectrochemistry). In this context, our research in this area is directed towards eliminating the waste by producing the oxidant/reducing agent in the reaction system itself, regenerating the catalyst at the end of the photocatalytic process, and only using sunlight as an energy source which is abundant, recyclable and environmentally viable. We also intend to avoid where possible the use of auxiliary substances including solvents and employing as recyclable manganese complexes developed in our laboratory. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

MARCHI, RAFAEL C.; AGUIAR, INARA; CAMILO, MARIANA R.; BRAGA, ADRIANO H.; DO NASCIMENTO, EDUARDO S. P.; SANTANA, VINICIUS T.; NASCIMENTO, OTACIRO R.; CARLOS, ROSE M.. Photochemical Properties of a Mononuclear Mn(I) Triscarbonyl Complex in Water: An Insight into Different Oxidation States. CHEMISTRYSELECT, v. 6, n. 33, p. 8746-8753, SEP 7 2021. (19/21143-0, 11/06244-3, 14/12538-8)