Maretva Baricot Mendoza Supervisor Dr. Josep Font Capafons

1. Experimental design for the functionalization of activated carbon as catalyst in Catalytic wet air oxidation of phenol Maretva Baricot Mendoza Supervisor Dr. Josep Font Capafons Chemical Reaction Engineering and Process Intensification Group, Department of Chemical Engineering, Universitat Rovira i Virgili Tarragona, February 3rd 2005

2. Content • Introduction • State of the art • Objectives • Methodology • Expected Results • Future work 2/13

3. Introduction Adsorption Membranes Filtration Ultrafiltration Reverse osmosis Chemical Oxidation Biological Treatments Environmental problem 3/13

4. Introduction Growing interest!!! Activated Carbon What is it ? Carbonaceous materials, highly crystalline form Extensively developed internal pore structure Adsorption, catalyst support but lately….. As catalyst itself!!! 4/13

5. State of the Art Phenolics Carbonyls Carboxyls Quinones Lactones Anhydrides Most common functional groups Characterization of carbon surface Chemical titrations Temperature programmed desorptions Infrared and X-ray photoelectron spectroscopy 5/13

6. State of the Art Carboxylic acid Lactone Phenol Carbonyl Anhydride Ether Quinone Functional groups 6/13

7. State of the Art Herbicides Activated carbon as catalyst in the oxidative dehydrogenation of ethylbenzene Modified AC Baçaoui et al Environ. Sci. & Technol, 2002. 36(17): p. 3844-3849 Pereira et al Appl. Catal., A, 1999. 184(1): p. 153-160 7/13

8. State of the Art CREPI Phenol oxidation in a Trickle bed reactor (TBR) @ 160ºC and Oxygen partial pressure 0,82 MPa(1) Conversion up to 99 % Commercial activated carbon as Catalyst (1) J. Chem. Technol. Biotechnol., 2001. 76(7): p. 743-751 8/13

9. Objectives Secondary Superficial functional groups Carbon texture Defunctionalization-Refunctionalization process Main Design an experimental procedure to functionalize activated carbon in order to obtain a good surface chemistry that improves the catalytic activity of carbon in the TBR. 9/13

10. Methodology Defunctionalization Heat treatment under Inert atmosphere Formation of specific surface functional groups Varying T, PO2 and time Refunctionalization Heat treatment under Oxygen and Nitrogen atmosphere Carbon treatment Elimination of surface functional groups Temperatures ranges 10/13

11. Methodology Adsorption tests Catalytic activity tests MAC tests Set of Modified Activated Carbon MAC Batch configuration TBR, Milder conditions From Refunctionalization Stage 11/13

12. Methodology MAC characterization Chemical titrations Thermogravimetric analysis + Thermal programmed desorptions TGA + TPD Infrared Spectroscopy From the set of MAC those that shows better performance as catalyst and adsorptive material… 12/13

13. Expected Results • Clarification of the influence of the surface chemistry on the AC catalytic performance • Determination of better surface chemistry on activated carbon for it to show catalytic activity • Obtaining a better catalyst for phenol oxidation than commercial AC • Procedure to design tailor made AC active for CWAO, from any source 13/13

14. Future work • Develop an experimental procedure combining oxidizing treatments and characterization techniques to obtain catalyst useful in oxidation of several compounds as halogenated phenols • Improve adsorptive performance of AC with chemical surface modification • Establish experimental procedures to specifically functionalize AC surface in order to improve its behavior as catalyst, support or adsorptive material 14/13

15. Questions Thanks for your attention!!! ???? Questions