GB/T 29914-2025Oxidation catalysts for diesel vehicle exhaust purification (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part

1.Structure and Drafting Rules of Standardization Documents". Drafting. This document replaces GB/T 29914-2013 "Oxidation Catalysts for Exhaust Gas Purification in Diesel Vehicles". Compared with GB/T 29914-2013, it includes the following improvements. Aside from structural adjustments and editorial changes, the main technical changes are as follows:

a) Added product labeling (see Chapter 4);

b) The catalytic performance requirements have been changed (see 5.3,

4.2 of the.2013 version);

c) An increased requirement for the plugging rate has been added (see 5.5);

d) Added requirements for coating peeling rate (see 5.6);

e) Increased coating load requirements (see 5.8);

f) The methods for testing appearance requirements (see 6.2,

5.5 of the.2013 edition) and the methods for testing catalytic performance (see 6.3,.2013 edition) have been changed. (See section

5.2 of the.2013 edition), exhaust back pressure testing method (see section 6.4, section

5.7 of the.2013 edition), precious metal content testing method (see section 6.7, section

5.7 of the.2013 edition). Version 5.6);

g) Added methods for detecting pore blockage rate (see 6.5), coating peeling rate (see 6.6), and coating load (see 6.8);

1 Scope

GB/T 29914-2025 is the Chinese national standard covering the diesel oxidation catalyst - the conversion of carbon monoxide and hydrocarbons and the light-off temperature at which it starts, the precious metal loading, the sulfur and thermal ageing that deactivate it, and the back pressure it adds. Issued on 31 October 2025, it has been in force since 1 May 2026, replacing GB/T 29914-2013.

This document specifies the product marking, technical requirements, and inspection rules for diesel vehicle exhaust purification oxidation catalysts, and describes the corresponding requirements. Experimental methods. This document applies to diesel fuels that use cordierite honeycomb ceramic materials as a carrier and load active components such as rare earth elements, precious metals, or other metals. Vehicle exhaust purification oxidation catalyst.

2 Normative references

The contents of the following documents, through normative references within the text, constitute essential provisions of this document. Dated citations are listed below. For references to documents, only the version corresponding to that date applies to this document; for undated references, the latest version (including all amendments) applies. This document.

GB/T 5181 Automobile Emissions Terms and Definitions

GB/T 8170 Rules for rounding off numerical values and the representation and determination of limiting values

GB 17691 Emission Limits and Measurement Methods for Pollutants from Heavy-Duty Diesel Vehicles (China VI Stage)

GB/T 18881-2017 Catalysts for Exhaust Purification in Light-Duty Gasoline Vehicles

GB/T 25994-2010 Cellular ceramics

HJ451-2008 Technical Requirements for Environmental Protection Products. Diesel Vehicle Exhaust Aftertreatment Devices Determination of Platinum, Palladium, and Rhodium in

HJ509 Automotive Ceramic Catalytic Converters. Inductively Coupled Plasma Atomic Emission Spectrometry and Inductively Coupled Plasma Spectrometry, etc. Inductively coupled plasma mass spectrometry

QC/T 829-2019 Technical Requirements for Exhaust Aftertreatment Systems of Diesel Vehicles

3 Terms and Definitions

The terms and definitions defined in GB/T 5181 and QC/T 829-2019, as well as the following terms and definitions, apply to this document.

3.1 light-duty diesel vehicle Diesel vehicles with a maximum gross vehicle weight not exceeding 3500 kg.

3.2 Heavy-duty diesel vehicle Diesel vehicles with a maximum gross vehicle weight exceeding 3500 kg.

3.3 DOC Installed in the exhaust system of diesel vehicle engines, it reduces carbon monoxide (CO) and hydrocarbons in the exhaust through a catalytic oxidation reaction. It reduces emissions of pollutants such as HC, and also has the ability to oxidize nitric oxide (NO) to nitrogen dioxide (NO2) and oxidize liquid hydrocarbons from fuel oil. Catalysts that increase catalyst temperature.