Paul Chin, Ph.D. Department of Chemical and Biomolecular Engineering College of Engineering 1 (EB1) 911 Partners Way Raleigh, NC 27695-7905 Phone: (919) 515-8757 Fax: (919) 515-3465 Rooms EB1 2023 (office) & 2089 (lab) Website: http://www4.ncsu.edu/~pchin Email: paul (dot) chin (@) ncsu (dot) edu

• Chin P., Yang L.P., Ollis D.F., "Formaldehyde Removal from Air Via a Rotating Adsorbent Combined with a Photocatalyst Reactor: Kinetic Modeling," Journal of Catalysis 2006, 237 1, 29-37.
• Chin P., Ollis D.F., "Decolorization of Organic Dyes on Pilkington Activ^TM Photocatalytic Glass," Catalysis Today - M.A. Vannice Festschrift 2007, 123 1-4, 177-188.
• Chin P., Roberts G.W., Ollis D.F., "Kinetic Modeling of Photocatalyzed Soot Oxidation on Titanium Dioxide Thin Films," Industrial & Engineering Chemistry Research - Alberto Cassano Festschrift 2007, 46 23, 7598-7604.
• Chin P., Ollis D.F., "Design Approaches for a Cycling Adsorbent/Photocatalyst System for Indoor Air Purification: Formaldehyde Example," Journal of the Air & Waste Management Association 2008, 58 4, 494-501.
• Chin P., Grant C.S., Ollis D.F., "Quantitative Photocatalyzed Soot Oxidation on Titanium Dioxide," Applied Catalysis B: Environmental, article in press.

• Chin P., Yang L.P., Ollis D.F., "Formaldehyde Removal from Air via a Rotating Adsorbent Combined With a Photocatalyst Reactor: Kinetic Model", Southeastern Catalysis Society Symposium, Asheville, NC, September 26, 2005.
• Chin P., Yang L.P., Ollis D.F., "Kinetic Model of Formaldehyde Removal from Air Using a Rotating Adsorbent Combined With a Photocatalytic Reactor", TiO₂-10 International Conference on Photocatalysis, Chicago, IL, October 23-27, 2005.
• Chin P., Ollis D.F., "Design Approaches for a Cycling Adsorbent/Photocatalyst System for Indoor Air Purification: Formaldehyde Example", Air and Waste Management Association 99th Annual Conference, New Orleans, LA, June 20-23, 2006.
• Chin P., Ollis D.F., "Design Approaches for a Cycling Adsorbent/Photocatalyst System for Indoor Air Purification: Formaldehyde Example" poster, Air and Waste Management Association Indoor Environmental Quality: Problems, Research and Solutions, Durham, NC, July 17-19, 2006.
• Chin P., Ollis D.F., "Decolorization of Organic Dyes on Pilkington Activ^TM Self-Cleaning Photocatalytic Glass", TiO₂-11 International Conference on Photocatalysis, Pittsburgh, PA, September 25-28, 2006.
• Ollis, D.F., Chin P., "Kinetics of Photocatalyzed Film Removal", ACS and AIChE Symposium on Applied Chemistry and Engineering, I&EC 38 session, 233^rd ACS National Meeting, Chicago, IL, March 26, 2007.
• Chin P., "Kinetics of Photocatalytic Degradation Using Titanium Dioxide Thin Films", Schoenborn oral presentation competition, Raleigh, NC, March 29, 2007.
• Chin P., Roberts G.W., Ollis D.F., "Photocatalyzed Soot Oxidation on Titanium Dioxide Thin Films: Kinetic Modeling" poster, Second International Conference on Semiconductor Photochemistry, Aberdeen, Scotland, UK, July 23-25, 2007.
• Chin P., Roberts G.W., Ollis D.F., "Photocatalyzed Soot Oxidation on Titanium Dioxide Thin Films", ACS Division of Catalysis and Surface Science Secretariat, Photocatalysis session, 234^th ACS National Meeting, Boston, MA, August 21, 2007.
• Chin P., Roberts G.W., Ollis D.F., "Photocatalyzed Soot Oxidation on Titanium Dioxide Thin Films", TiO₂-12 International Conference on Photocatalysis, Niagara Falls, NY, September 24-27, 2007.
• Chin P., Grant C.S., Ollis D.F., "Quantitative Photocatalyzed Soot Oxidation on Titanium Dioxide Thin Films", 82nd ACS Colloid & Surface Science Symposium, Surface Science and Catalysis 2: Applications session, Raleigh, NC, June 16, 2008.
• Chin P., Grant C.S., Ollis D.F., "Quantitative Photocatalyzed Soot Oxidation on Titanium Dioxide Thin Films", TiO₂-13 International Conference on Photocatalysis, San Diego, CA, September 25, 2008.

PhD Disseration Summary

Titanium dioxide (TiO₂), a semiconductor metal oxide, has been used in heterogeneous photocatalysis for the destruction of organic, inorganic, and biological materials. The chief objectives of my doctoral research are to generate kinetic data and to develop engineering models for photocatalytic oxidation (PCO) using TiO2 thin films for current challenges in "solid"-solid and air-solid environmental remediation. Three topics are studied in detail:

i. TiO₂ Photocatalytic Oxidation for Formaldehyde Removal from Air (Air-Solid)

Formaldehyde (CH2O) is a toxic, organic indoor air contaminant present in industrial, commercial, and residential buildings. The World Health Organization (WHO) set the permissible CH2O indoor air concentration at a very low level of 0.1 mg/m3. Since the TiO2 PCO kinetics are first order for CH2O concentrations below 10 ppm, pre-concentration of CH2O can increase its destruction rate and improve process performance. A novel rotating honeycomb adsorbent coupled with a PCO reactor (photoreactor) was demonstrated by F. Shiraishi and coworkers for CH2O oxidation. They showed that their cyclic adsorbent / photoreactor could oxidize CH2O to concentrations below the WHO guideline, but they made no attempt to model the system. In this project we modeled their batch system at transient and steady states. In addition, we applied the batch model kinetic parameters to design a continuous system for typical residential home challenges.

ii. TiO₂ Photobleaching of Dried Dye Layers as a Field Analysis Method ("Solid"-Solid)

Technological advances in the past decade allow glass manufacturers to deposit thin, photoactive, nano-sized TiO2 layers (10-20 nm) on glass, with trademark names such as Pilkington ActivTM, PPG SuncleanTM, and Saint-Gobain BiocleanTM. These products are billed as "self-cleaning" surfaces because they utilize TiO2 photocatalytic oxidation (PCO) and photo-induced superhydrophilicity (PSH) properties. The PCO activity causes progressive oxidation of adsorbed oxidizable molecules and organic particulate matter, while the PSH property allows for water washing removal of partially oxidized molecules and particulates from the TiO2 surface. Field installation of such "self-cleaning" window glass for office buildings or residential homes will require the creation of field tests to characterize the initial and continuing catalyst activity variations with time and environmental conditions. In this project we continued the recent work by Julson and Ollis on PCO of a sub-monolayer dry dye layer on optically opaque TiO2 powder to determine its potential as an analysis method to measure the PCO activity of commercial Pilkington ActivTM TiO2-coated transparent (optically dilute) glass.

iii. TiO₂ Photooxidation of Deposited Soot Layers ("Solid"-Solid)

A major contribution to visual degradation of exterior surfaces (e.g., buildings and statues) in urban environments, especially the major cities of industrialized countries, is the deposition of particulate soot from diesel automobiles, heavy equipment, forest fires, burning wastes, and other incomplete combustion sources of heavier liquid fuels. Moreover, soot accounts for 5-15% contribution to reduced visibility in the United States. Therefore, a recent area of TiO2 research has focused on tackling this issue. Destruction of deposited soot layers by TiO2 photocatalysis had been reported recently, but there was (a) an inability to deposit a soot layer of uniform thickness on the TiO2 surface and (b) a lack of rigorous modeling to describe the PCO kinetics of soot disappearance. We developed a method to apply a uniform, thin soot layer on TiO2 thin films. Laboratory studies were conducted to collect quantitative kinetic data via quartz crystal microbalance monitoring, and a mixed series / parallel kinetic reaction model was developed to describe the kinetics of TiO2 PCO on these porous carbonaceous layers.

Previous Masters Thesis Research Completed At North Carolina State University

• Roberts G.W, Chin P., Sun X., Spivey J.J., "Preferential Oxidation of Carbon Monoxide with Pt/Fe Monolithic Catalysts: Interactions Between External Transport and the Reverse Water-Gas-Shift Reaction", Applied Catalysis B - Environmental, 2003, 46 (3), p. 601-611
• Chin P., Sun X., Roberts G.W., Spivey J.J., "Preferential Oxidation of Carbon Monoxide with Iron-promoted Platinum Catalysts Supported on Metal Foams", Applied Catalysis A - General, 2006, 302 (1), p. 22-31

• Chin P., Sun X., Roberts G.W., Spivey J.J., "Selective Oxidation of CO in H₂-containing Gases using Metal Foam Catalyst Supports", Southeastern Catalysis Society Fall Symposium, Asheville, NC, September 30, 2002.
• Sun X., Roberts G.W., Spivey J.J., Chin P., "Selective Oxidation of CO in H₂-containing Gases using Metal Foam Catalyst Supports", AIChE 2002 Fall Annual Meeting, Indianapolis, IN, November 6, 2002.
• Roberts G.W., Spivey J.J., Chin P., Sun X., "On Choosing a Catalyst Support: Applications to Fuel Cell Technology", AIChE 2003 Spring Topical Conference Presentation, New Orleans, LA, March 31, 2003.
• Chin P., Sun X., Roberts G.W., Spivey J.J., "Considerations for Catalyst Support Selection in Fuel Cell Applications" poster, Southeastern Catalysis Society Spring Symposium, Asheville, NC, April 13, 2003.
• Chin P., Sun X., Roberts G.W., Spivey J.J., "Selective Oxidation of CO on Metal-foam Supported Pt-Fe Catalysts" poster, 18th North American Catalysis Society Meeting, Cancun, Mexico, June 4, 2003.
• Chin P., Sun X., Roberts G.W., Spivey J.J., "CO Preferential Oxidation Supports Study for Fuel Cell Applications", DOE NETL UCR/HBCU/OMI contractor's meeting, Pittsburgh, PA, June 3, 2003.
• Chin P., Roberts G.W., Spivey J.J., "Characterization of PROX Catalysts on Structured Supports ", DOE NETL UCR/HBCU contractor's meeting, Pittsburgh, PA, June 9, 2004.
• Spivey, J.J., Roberts G.W. Lamb H.H., Goodwin Jr. J.G., Butcher K., Chin P., Sigmon S., Silletti B., Sirijarhuphan A., "Catalytic Approaches to the Development of Clean Energy Technologies", ACS Petroleum Division Symposium on "Advances in Petroleum Processing and Clean Energy Technology" keynote presentation, Philadelphia, PA, August 22-26, 2004.
• Chin P., Roberts G.W., Spivey J.J., "Characterization of PROX Catalysts on Structured Supports" poster, Southeastern Catalysis Society Symposium, Asheville, NC, September 26, 2004.
• Chin P., Roberts G.W., Spivey J.J., "Characterization of PROX Catalysts on Structured Supports", AIChE 2004 Fall Annual Meeting, Austin, TX, November 10, 2004.
• Chin P., Breault R., Roberts G.W., Spivey, J.J., "Reformulation of Coal-Derived Transportation Fuels: Preferential Oxidation of Carbon Monoxide on Structured Supports", 22nd International Pittsburgh Coal Conference, Pittsburgh, PA, September 12-15, 2005.