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WP4: Evaluation of catalyst activity and stability. Slide 1. Workpackage:. WP4. Evaluation of catalyst activity and stability. Presenter:. MTEC - Angkhana Jaroenworaluck. Collaborating teams:. UoB / URJC UCL / UoR, MTEC / SIRIM / VAST-ICT. WP4: Tasks & Teams. Slide 2.
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WP4: Evaluation of catalyst activity and stability Slide 1 Workpackage: WP4. Evaluation of catalyst activity and stability Presenter: MTEC - Angkhana Jaroenworaluck Collaborating teams: UoB / URJC UCL / UoR, MTEC / SIRIM / VAST-ICT
WP4: Tasks & Teams Slide 2
WP4: Objectives Slide 3 1. Core/shell nanostructure materials 2. New photocatalyst types Tested photocatalysts to be further characterised to maximise results WP2 WP5 New materials to increase visible light activity Kinetic and Mechanism Studies WP4 TiO2 photocatalysts deposited on various type of supports Test key parameters for the reactor design WP3 WP6 Improving TiO2 based systems Reactor design, evaluation & scale up Standardization for Photocatalyst reactions
Deliveries Slide 4 Due No. Description D4.1 M9 Report on the optimum design of a test reactor for the project Performance of new generation of photo-catalysts D4.2 M42 M42 Industry effluent degradation performance D4.3
Milestones Slide 5 M12-18 Milestone Milestone name Expected Means of verification Standardised reactor constructed in all sites working on WP4.2 and 4.3. Screening reactor operational MS14 M12 Initial kinetic analysis doped and non-doped TiO2 powders MS15 Kinetic profiles available M18
Outline Task 4.1. Standardisation of Test Conditions 1.- Preliminary design of the photoreactor 2.- Proposed reactor design 6
Task 4.1. Standardisation of Test Conditions 1.- Preliminary design of the photoreactor • Objective: simple reactor to test different catalysts at equal conditions at the different research locations. • The conditions that should be equal, as previously discussed, are: temperature, pH, oxygen supply, indicator concentration and light intensity. • To measure the pH, oxygen, and temperature there should be 3 access points for sensors. • To be able to control the temperature the reactor should have a cooling/heating jacket. • To ensure an equal light intensity the distance between the source and the catalyst and the height of water should be fixed.
Task 4.1. Standardisation of Test Conditions 1.- Preliminary design of the photoreactor Basic Design I
Task 4.1. Standardisation of Test Conditions 1.- Preliminary design of the photoreactor Basic Design I The light source will be placed on top of the reactor vessel and integrated with the required access points and sample point To ensure a fixed distance between the light source and the catalyst a frame to hold the immobilized catalyst.
Task 4.1. Standardisation of Test Conditions 2.- Proposed Reactor Design Reactor Design Considerations FLUID DYNAMICS AND HEAT TRANSFER: Perfectly mixed conditions should be ensured to: - Discard external mass transport effects Reaction kinetics control. - Homogeneous composition in the withdrawal of samples. - Isothermal conditions. Proposals: - Magnetic stirring at the bottom. - Air bubbling to improve mixing. - Position of the catalyst inside the liquid at a height around 2/3. - Diameter of the catalyst 1/2 of the reactor diameter. - Cooling jacket to keep temperature constant (bad for wall reflectivity)
Task 4.1. Standardisation of Test Conditions 2.- Proposed Reactor Design Reactor Design Considerations RADIATION TRANSFER: Homogeneous irradiation of the catalyst Homogenous reaction rate. Low LEDs-catalyst distance Higher radiation flux (especially for non-reflective walls) Low LEDs-catalyst distance Risk of wetting the LEDs circuits. Proposals: - Air chamber above the liquid surface required for air equilibrium. - Highly reflective walls to increase radiation flux and to improve homogeneity. - Optimal distribution of the LED sources to improve homogeneity.
Task 4.1. Standardisation of Test Conditions 2.- Proposed Reactor Design Reactor Design Considerations CHEMICAL REACTION KINETICS: Constant dissolved O2 concentration: Simplifies kinetics and avoids measurement. Nearly constant reaction volume: (withdrawn samples < 10% total volume). Relatively short reaction time: - Reduces heating problems. - Reduces stripping of chemicals to the gas phase. - Low conversion < 10% Initial reaction rate conditions, intermediates effects can be discarded in the kinetics. Proposals: - Relatively high reaction volume - Sampling below <10% of the total reaction volume. - Conversion around 10% optimal for getting significant data above the experiment error of the analytical method keeping initial reaction rate conditions.
Task 4.1. Standardisation of Test Conditions 2.- Proposed Reactor Design Proposed Reactor Dimensions Reactor diameter: D_R = 80 mm Liquid height: H_L = 50 mm Sample volume: V_S = 2.5 mL Sample number (máx): N_S = 10 Catalyst diameter: D_C = 40 mm (1/2 of the reactor) Catalyst height: H_C = 30 mm above bottom, 20 mm below surface. LEDs height: H_LED = 80 mm (50 mm from catalyst, 30 mm air) Reaction volume V_L = 250 mL Max volume V_Smax = 25 mL Min H_L = 45 mm (DH_L 10%)
Task 4.1. Standardisation of Test Conditions 2.- Proposed Reactor Design
Task 4.1. Standardisation of Test Conditions • Number, dimensions and arrangement of the LED. LEDs Circuit Preliminary Design Possibility of switching off some LEDs to modify irradiation flux
Task 4.1. Standardisation of Test Conditions 2.- Proposed Reactor Design LED Circuit Reactor Vessel
Task 4.1. Standardisation of Test Conditions 2.- Proposed Reactor Design Cover / Catalyst Frame Openings LEDs Circuit position Catalyst Holder
Slide 18 Standardization bodies on photocatalyst materials (CEN vs ISO)
CEN Slide 19 CEN: European committee for standardization CEN/TC386-(Photocatalysis) established in 11/2008 WG3: Water purification WG6: Light source WG8: Microbiological effects Secretariat: AFBOR (France) Chairman: Dr. Pascal KALUZNY (France) Source: http://www.cen.eu and http://www.dri.mmu.ac.uk
Slide 20 00386001 Project reference: FprCEN/TS16599 Title: Photocatalysis-Irradiation conditions for testing photocatalytic properties of semiconducting materials and the measurement of these conditions Candidate citation in OJEU* :No (-) Current status: Under Approval DAV: 2013-12 (*) OJEU-Official Journal of the European Union Source: http://www.cen.eu
ISO Slide 21 ISO: International organization for standardization ISO/TC206-Fine Ceramics established in 1992 with JISC as secretariat Secretariat: Dr. Shuji Sakaguchi (AIST, Japan) Chairman: Dr. Tai-Kyu Lee (Nanopac Co., Korea) (WG37: Test methods for photocatalytic materials) Convenor: Dr. Koji TAKEUCHI (AIST, Japan) Source: http://www.iso.org
Published standards-1 Slide 22 ISO/TC206: Photocatalyst materials / water purification/ anti-bacteria / light source ISO 10676:2010 Fine ceramics (advanced ceramics, advanced technical ceramics) -- Test method for water purification performance of semiconducting photocatalytic materials by measurement of forming ability of active oxygen. Abstract ISO 10676:2010 describes a test method covering photocatalytic materials formed on, or attached to, another material surface for the purpose of decomposing, and thus eliminating, the pollutants in water, using photocatalytic performance. This test method is applicable to photocatalytic materials under UV irradiation, and not under visible light irradiation. Source: http://www.iso.org
Published standards-2 Slide 23 ISO 10677:2011 Fine ceramics (advanced ceramics, advanced technical ceramics) -- Ultraviolet light sourcefor testing semiconducting photocatalytic materials. Abstract ISO 10677:2011 describes an ultraviolet (UV) light source and specifies a method of measuring the radiation intensity which is used in testing the performance of semiconducting photocatalytic materials in a laboratory. Source: http://www.iso.org
Published standards-3 Slide 24 ISO 10678:2010 Fine ceramics (advanced ceramics, advanced technical ceramics) -- Determination of photocatalytic activity of surfacesin an aqueous medium by degradation of methylene blue. Abstract ISO 10678:2010 specifies a method for the determination of the photocatalytic activity of surfaces by degradation of the dye molecule methylene blue (MB) in aqueous solution using artificial ultraviolet (UV) radiation, and characterizes the ability of photoactive surfaces to degrade dissolved organic molecules on ultraviolet radiation. The test method specified is also applicable to evaluation of the specific photocatalytic self-cleaning activity of surfaces covered with respective coatings. This method is not applicable to characterizing the photoactivity of surfaces on visible illumination, regarding direct soiling, degradation of gaseous molecules and the determination of antimicrobial photoactivity of surfaces. Source: http://www.iso.org
Published standards-4 Slide 25 ISO 13125:2013 Fine ceramics (advanced ceramics, advanced technical ceramics) -- Test method for antifungal activity of semiconducting photocatalytic materials. Abstract ISO 13125:2013 specifies a test method covering the determination of the antifungal activity of materials that contain a photocatalyst or have photocatalytic films on their surface, by counting the number of pre-incubated fungal spores that survive exposure to ultraviolet (UV-A) light. ISO 13125:2013 provides for the assessment of different kinds on materials used in various applications, such as construction materials in flat coating, sheet, board or plate form, etc. Powder, granular, fibrous or porous photocatalytic materials are not included. Values expressed in ISO 13125:2013 are in accordance with the International System of Units (SI). Source: http://www.iso.org
Published standards-5 Slide 26 ISO 27447:2009 Fine ceramics (advanced ceramics, advanced technical ceramics) -- Test method for antibacterial activity of semiconducting photocatalytic materials. Abstract ISO 27447:2009 specifies a test method for the determination of the antibacterial activity of materials that contain a photocatalyst or have photocatalytic films on the surface, by measuring the enumeration of bacteria under irradiation of ultraviolet light. ISO 27447:2009 is intended for use with different kinds of semiconducting photocatalytic materials used in construction materials, in flat sheet, board, plate shape or textiles that are the basic forms of materials for various applications. It does not include powder, granular or porous photocatalytic materials. This test method is usually applicable to photocatalytic materials produced for an antibacterial effect. Other types of performance of photocatalytic materials, i.e. decomposition of water contaminants, self-cleaning, antifogging and air purification, are not determined by this method. The values expressed in ISO 27447:2009 are in accordance with the International System of Units (SI). Source: http://www.iso.org
Standards under development Slide 27 ISO/FDIS 14605 Fine ceramics (advanced ceramics, advanced technical ceramics) -- Light source for testing semiconducting photocatalytic materials used under indoor lighting environment. ISO/DIS 17094 Fine ceramics (advanced ceramics, advanced technical ceramics) -- Test method for antibacterial activity of semiconducting photocatalytic materials under indoor lighting environment. Source: http://www.iso.org
New proposal for water purification Slide 28 Standards to be proposed: Test method for environment purification performance of photocatalyst and applied materials by dissolved oxygen consumption (Temperary) Proposed by: Dr. Koji TAKEUCHI (AIST, Japan) Dr. Tsutomu HIRAKAWA (AIST, Japan) Target dates of proposal and issue of the standards: JIS: Proposal FY 2012 Issued FY 2013 ISO: Proposal FY 2012 Issued FY 2017 Source: from Dr. Takeuchi (AIST, JAPAN), page 18 of 23souran_hyoujyunkiban.pdf
MB degradation test of P25 TiO2 Slide 29 Light source Light off - 24 h filtration Light on -150 min filtration MB concentration: 4 ppm UVA intensity: 50 W/m2
Future plans Slide 30 Make a simple reactor (closed system) of LED light source from UOB. Set test conditions: Light on-off, P25 TiO2 / MB concentrations / LED intensities. Compare reaction rate from all reactors used. Change catalyst types for the same test conditions. (started from powder type to pellets and 3D-porous TiO2 catalysts) 5. Draft scientific papers to be published. (if possible)
Slide 31 Thank You