BS EN 17120:2019 pdf download

BS EN 17120:2019 pdf download.Photocatalysis – Water purification – Performance of photocatalytic materials by measurement of phenol degradation
1 Scope
This document describes a test method to evaluate the performance of photocatalytic materials in water purification by measuring phenol degradation. This test method is applicable to photocatalytic materials in form of powders (suspensions in water, slurries) under UV irradiation. The photocatalytic performance of the tested material is assessed by the observed rate of phenol degradation at specified experimental conditions as determined by HPLC.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
EN 1484:1997, Water analysis – Guidelines for the determination of total organic carbon (TOC) and dissolved organic carbon (DOC)
CEN/TS 16599:2014, Photocatalysis 一Irradiation conditions for testing photocatalytic properties of semiconducting materials and the measurement of these conditions
ISO 8245:1999, Water quality – Guidelines for the determination of total organic carbon (TOC) and dissolved organic carbon (DOC)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
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5 Principle
A test solution is prepared by suspending a given amount of the material to be tested in water with the addition of a certain amount of phenol. The test solution is irradiated with UV in a batch photo-reactor under controlled conditions. The concentration of phenol is measured against irradiation time by HPLC with UV detection. The photocatalytic performance of the material is assessed by the observed rate of phenol degradation. Additional information regarding mineralization of phenol can be obtained by measuring the decrease of organic carbon (TOC or DOC) during the photocatalytic process [optional).
6 Interferences
The laboratories carrying out this test shall perform tests for possible interferences in the chromatographic system for measurement of phenol (HPLC) and in the TOC/DOC analyser (where applied). The laboratories shall document the absence of significant interferences that could affect the measurements of phenol/TOC/DOC.
A batch-type cylindrical photo-reactor cell made of pyrex glass, 5 cm in diameter and 100 ml volume with ability for magnetic or mechanical stirring is used. The temperature of the irradiated solution shall be measured and recorded inside the reactor during the test and should be kept within 25士5 °C. The irradiation source shall consist of any lamp able to excite the photocatalyst in UV such as quartz mercury vapor lamps, UV-A fluorescent lamps, Xenon lamps, LED, lamps consisting of a metal vapor element combined with tungsten incandescence elements, etC., as specified in the technical specification CEN/TS 16599:2014. The irradiation system should be checked according to the test method procedure [Clause 8) in the absence of test material (photocatalyst) to ensure that no significant degradation of phenol takes place [<5 % degradation) over the time of the test due to direct photolysis.