Optimizing Noble Metals Adsorption For Catalyst Synthesis Using Strong Electrostatic Adsorption (Sea)

Hansen Mou

School Name

South Carolina Governor's School for Science and Mathematics

Grade Level

12th Grade

Presentation Topic

Chemistry

Presentation Type

Mentored

Mentor

Mentor: John R. Regalbuto, Department of Chemical Engineering, University of South Carolina

Written Paper Award

2nd Place

Abstract

This research examines the strong electrostatic adsorption (SEA) method of catalyst formation using carbon black, alumina, and silica supports at various pH. At a certain pH, the functional groups on the support’s surface reach a maximum level of ionization, causing the support to adsorb the maximum amount of precursor. This point of maximum ionization differs for each support, and it needs to be known in order to make the best catalysts possible with this method. This research examined carbon black (Darco G-60, Oxidized VXC 72), alumina (SBA 200), and silica (Aerosil 380) supports for their maximum uptake of PTA, PdTA, PTC, PdCl42-, and CoHA precursors via uptake surveys extending from pH 1 to 14. The results showed that SBA 200 adsorbed the most PTC at about pH 4.5, Darco G-60 had a maximum adsorption of PdCl42- at about pH 2, Oxidized VXC 72 had maximum adsorptions of PTA and PdTA at about pH 12, and Aerosil 380 had a maximum adsorption of CoHA at about pH 12. From this and previous knowledge of the materials and this concept, it is possible to accurately document the optimal uptake pH for other support/precursor combinations by narrowing the pH range for testing. If the point of zero charge (PZC) of the support and the ionic charge of the dissolved precursor are known, a range of possible optimal pH can be determined, allowing future experiments to focus on those points exclusively to save time and resources.

Start Date

4-11-2015 9:30 AM

End Date

4-11-2015 9:45 AM

COinS
 
Apr 11th, 9:30 AM Apr 11th, 9:45 AM

Optimizing Noble Metals Adsorption For Catalyst Synthesis Using Strong Electrostatic Adsorption (Sea)

This research examines the strong electrostatic adsorption (SEA) method of catalyst formation using carbon black, alumina, and silica supports at various pH. At a certain pH, the functional groups on the support’s surface reach a maximum level of ionization, causing the support to adsorb the maximum amount of precursor. This point of maximum ionization differs for each support, and it needs to be known in order to make the best catalysts possible with this method. This research examined carbon black (Darco G-60, Oxidized VXC 72), alumina (SBA 200), and silica (Aerosil 380) supports for their maximum uptake of PTA, PdTA, PTC, PdCl42-, and CoHA precursors via uptake surveys extending from pH 1 to 14. The results showed that SBA 200 adsorbed the most PTC at about pH 4.5, Darco G-60 had a maximum adsorption of PdCl42- at about pH 2, Oxidized VXC 72 had maximum adsorptions of PTA and PdTA at about pH 12, and Aerosil 380 had a maximum adsorption of CoHA at about pH 12. From this and previous knowledge of the materials and this concept, it is possible to accurately document the optimal uptake pH for other support/precursor combinations by narrowing the pH range for testing. If the point of zero charge (PZC) of the support and the ionic charge of the dissolved precursor are known, a range of possible optimal pH can be determined, allowing future experiments to focus on those points exclusively to save time and resources.