1、BS EN 16845-1:2017Photocatalysis Anti-soilingchemical activity usingadsorbed organics under solid/solid conditionsPart 1: Dyes on porous surfacesBSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS EN 16845-1:2017 BRITISH STANDARDNational forewordThis British Standard
2、is the UK implementation of EN 16845-1:2017.The UK participation in its preparation was entrusted to TechnicalCommittee RPI/13, Advanced technical ceramics.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include al
3、l the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2017. Published by BSI Standards Limited 2017ISBN 978 0 580 89121 2ICS 25.220.20Compliance with a British Standard cannot confer immunity fromlegal obligations.This British St
4、andard was published under the authority of theStandards Policy and Strategy Committee on 31 March 2017.Amendments/corrigenda issued since publicationDate Text affectedBS EN 16845-1:2017EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 16845-1 March 2017 ICS 25.220.20 English Version Photocatalys
5、is - Anti-soiling chemical activity using adsorbed organics under solid/solid conditions - Part 1: Dyes on porous surfaces Photocatalyse - Activit chimique anti-salissures laide de matires organiques adsorbes dans des conditions solide/solide - Partie 1 : Colorants sur des surfaces poreuses Photokat
6、alyse - Schmutzabweisende, chemische Aktivitt unter Verwendung adsorbierender organischer Stoffe im Zustand fest/fest - Teil 1: Farbstoffe auf porsen Oberflchen This European Standard was approved by CEN on 14 November 2016. CEN members are bound to comply with the CEN/CENELEC Internal Regulations w
7、hich stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This
8、European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN member
9、s are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal
10、, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2017 CEN All rights of exploitation in a
11、ny form and by any means reserved worldwide for CEN national Members. Ref. No. EN 16845-1:2017 EBS EN 16845-1:2017EN 16845-1:2017 (E) 2 Contents Page European foreword . 4 1 Scope 5 2 Normative references 5 3 Terms and definitions . 5 4 Symbols and abbreviations . 6 5 Principle . 7 6 Instruments . 7
12、 6.1 Spraying system . 7 6.2 Analytical balance . 9 6.3 Diffuse Reflectance Spectrometer 10 6.4 Light source 10 6.5 Other experimental needs 10 7 Materials 10 7.1 Dyes used 10 7.2 Preparation of Solutions to Spray 11 7.3 Test Samples 11 7.4 Other experimental needs 11 8 Procedure 11 8.1 General Aspe
13、cts 11 8.1.1 General . 11 8.1.2 Initial set up and calibration 12 8.1.3 Measurement of the Reflectance Spectra of the Surface 12 8.2 Optimization of the Experimental Setup . 12 8.2.1 General . 12 8.2.2 Optimization of the Spraying Distance and Flow 12 8.2.3 Measurement of the Spraying Flow Rate . 12
14、 8.2.4 Evaluation of the Deposition Rate (DR) . 13 8.3 Test Procedure 13 8.3.1 Evaluation of the Dirt Parameter Calibration Function . 13 8.3.2 Choice of Test Sample Covered with Dye for Irradiation . 14 8.3.3 Evaluation of the Photocatalytic Self-cleaning Performance . 14 8.3.4 Results 15 9 Calcula
15、tion 15 9.1 General . 15 9.2 Spraying Flow (f) 15 9.3 Dirt Parameter 16 9.4 Covered Area 16 9.5 Deposition Rate . 17 9.6 Standard Spraying Time 17 9.7 Dirt Parameter Calibration Function 18 9.8 Remaining Dye (i) after Different Times of Irradiation. 18 9.9 Dye Half-Life . 18 10 Precision and Reprodu
16、cibility . 19 BS EN 16845-1:2017EN 16845-1:2017 (E) 3 11 Test Method for Samples with Low to Negligible Performance . 19 12 Test Report 19 Annex A (informative) Typical Experimental Data . 21 A.1 General . 21 A.2 Optimization of the Spraying Conditions (example) . 21 A.3 Measurement of the Spraying
17、Mass Flows (example) . 22 A.4 Measurement of the Covered Area (example) . 23 A.5 Evaluation of the Dirt Parameter Calibration Function (example) 25 A.6 Evaluation of the Self-cleaning Effect (example) . 27 Bibliography . 29 BS EN 16845-1:2017EN 16845-1:2017 (E) 4 European foreword This document (EN
18、16845-1:2017) has been prepared by Technical Committee CEN/TC 386 “Photocatalysis”, the secretariat of which is held by AFNOR. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by September 2017, and c
19、onflicting national standards shall be withdrawn at the latest by September 2017. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN shall not be held responsible for identifying any or all such patent rights. EN 16845, Photocata
20、lysis Anti-soiling chemical activity using adsorbed organics under solid/solid conditions, is dedicated to anti-soiling chemical activity using adsorbed organics under solid/solid conditions and is constituted by the following parts: Part 1: Dyes on porous surfaces; Part 2: Simulated weathering cond
21、itions. According to the CEN-CENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, Fra
22、nce, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 16845-1:2017EN 16845-1:2017 (E) 5 1 Scope This European Standard
23、specifies a test method for the evaluation of the photocatalytic self-cleaning performance of materials showing photocatalytic activity, usually based on semiconducting metal oxides such as titanium dioxide, by the measurement under solid/solid conditions of the decolouring ability under irradiation
24、 with ultraviolet light (UV-A) of a test sample on which a dye solution is sprayed and dried. This European Standard is intended for use with opaque and rough surfaces of different kinds, such as construction materials in flat sheet, board or plate shape, that are the basic forms of materials for va
25、rious applications. This European Standard also applies to fabric, plastic or composites containing photocatalytic materials that are not soluble in acetone. This European Standard does not apply to photocatalytic glass, granular materials (unless they are deposited in compact films or layers over f
26、lat solid surface) and flat non porous materials. The method evaluates only the self-cleaning ability of the material under ultraviolet light irradiation. It cannot be applicable to evaluate other performance attributes of photocatalytic materials, i.e. decomposition of water contaminants in liquid
27、or gas phases contacting the material, and antifogging and antibacterial actions. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For unda
28、ted references, the latest edition of the referenced document (including any amendments) applies. CEN/TS 16599, Photocatalysis - Irradiation conditions for testing photocatalytic properties of semiconducting materials and the measurement of these conditions CEN/TS 16981, Photocatalysis Glossary of t
29、erms EN ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories (ISO/IEC 17025:2005) 3 Terms and definitions For the purposes of this document, the terms and definitions given in CEN/TS 16981 and the following apply. 3.1 self-cleaning ability of a material to m
30、aintain clean or to clean itself if soiled on its surface 3.2 photocatalytic self-cleaning self-cleaning ability of a material as a consequence of the irradiation of the material surface with UVVISIR radiation 3.3 spraying distance distance from the outlet of the spraying gun (see experimental setup
31、) and the surface of the test sample BS EN 16845-1:2017EN 16845-1:2017 (E) 6 3.4 covered area CA area of the sample where the colour intensity is exp(2) 13,5% of the maximum intensity 3.5 dirt parameter DP dye amount spread or persistent over the sample surface 3.6 dirt parameter calibration functio
32、n mathematical function that describes the relation between the Dirt Parameter and the amount of dye spread over the sample surface 4 Symbols and abbreviations a, b, c polynomial constant parameters obtained by the fit using Formula (7) Anet() Net Absorbance of the dye covering of the sample surface
33、 at the wavelength CA Covered Area (cm2) Cdyeconcentration of the dye in the spraying solution (g cm3) dacdensity of acetone at the temperature of the measurement (g cm3) DP dirt parameter (nm): the parameter is indexed depending on the context DR deposition rate (g s1cm2) f volumetric spraying flow
34、 (cm3s1) Fimass flow (g s1) kdyefirst order kinetic constant of the specified dye for the photocatalytic self-cleaning process (min1) MW molecular weight n number of steps used for deposition of the dye on the sample surface; typically, n = 5, but can be larger if the surface is excessively wet R()
35、spectral reflectance at the wavelength of the sample surface; R() has indexes i and j referring to steps of spraying and illumination, respectively Rbackground() reflectance of the pristine surface at the wavelength SC standard dye covering defined in Table 2 (g cm2) T temperature in C tiirradiation
36、 time in min tsprspraying time (s), calculated as tspr= sprstdt /n W the full width at half maximum (FWHM) of the sprayed dye colour peak (cm) average covering of dye at the surface (g cm2); indexes i and j refer to steps of spraying and illumination, respectively omaximum average covering of dye at
37、 the surface (g cm2), obtained at sprstdt BS EN 16845-1:2017EN 16845-1:2017 (E) 7 wavelength (nm) maxwavelength (nm) at which there is a maximum of absorbance sprstdt standard spraying time (s) 1/2dyehalf-life of the dye for the photocatalytic self-cleaning process (min) 5 Principle This standard co
38、ncerns the comparison and the quality assurance of photocatalytic materials used as self-cleaning materials. The method described is intended to measure the photocatalytic self-cleaning performance of a photocatalytic material by evaluating its ability to clean its surface, previously covered by a k
39、nown amount of coloured organic compound, as a consequence of the exposition to ultraviolet light. A controlled amount of a dye solution dissolved in a volatile solvent (acetone) is spread on the tested surface by using a spraying gun. The photocatalytic material turns out to be covered by the solid
40、 dye. The relation between the amount of the spread dye and the spectrophotometric reflectance is defined in the calibration step. The calibration function involves the measurement of the reflectance spectra of the sample surface as a function of the dyes covering. Dyes used in separate experiments
41、are Metanil Yellow, Rhodamine B, and Methylene Blue. The test shall be carried out with the dye showing the maximum optical contrast with the material to be tested. Criteria for the choice of the best dye are here given (see 8.3.2). Optionally, the test can be carried out with the others dyes as the
42、 reactivity of each dye can depend on the specimen. The measurement with more than one dye is encouraged, but it is not compulsory. The self-cleaning activity measured by this test shall be referred to the used dye. The soiled surface is then irradiated in air by UV-A light under defined conditions
43、and the decrease of the dye amount on the surface is monitored by measuring the reflectance spectra of the surface of the test sample in the visible range. By using the calibration function the change of the reflectance spectra can be related to the kinetic of disappearance of the dye from the surfa
44、ce. The photocatalytic self-cleaning performance is determined as the half-life (minutes) of the dyes applied to the surface. 6 Instruments 6.1 Spraying system The method described in this standard relies on the possibility to cover the sample surface with the dye in a controlled way. A spraying sys
45、tem shall be used to spread over the sample surface a solution of the dye (dye solution) in volatile solvent (acetone). The spraying system consists of a sample support and in a pneumatic system under pressure able to spray the dye solution over the sample for different definite times. The dye solut
46、ion shall be spread by using a spraying gun that forms a circular spot. This involves a normal (Gaussian) distribution of the amount of dye centred in the spot of the dye on the surface. The amount of solution spread over the test sample is controlled by changing the spraying time (tspr) with a time
47、r that opens and closes, with a precision of 0,01 s, the dye solution flow. The relative distance and orientation between the gun and the sample shall be changed in a way to obtain a symmetric covering of the surface of the test sample and the desired surface covered area. Due to the normal distribu
48、tion of the colour intensity at the test piece surface, the dye surface covered area is defined as the area of the sample where the colour intensity is exp(2)approximately 13,5 % of the maximum intensity (see 8.2). The optimal distance from the gun outlet to the surface of the test sample is referre
49、d as the spraying distance. A sketch of the pneumatic spraying system and of the sample support is shown in Figure 1 and Figure 2. BS EN 16845-1:2017EN 16845-1:2017 (E) 8 One pressurized (3,0 0,1) bar) bottle containing water and at least one pressurized (3,0 0,1) bar) bottle containing the dye solution (spraying liquids) are connected to the spraying gun by tubes made of materials resistant to the used solvent (for example PTFE (polytetrafluoroethylene). The bottles and gun materials shall also be chemically inert to
