Study on the quantitative method of formaldehyde release from artificial boards and their products

Introduction

Authors: Yu Haixia, Fang Chongrong, Xu Manping, Gan Meijiao, Yang Weiming, Zhuang Xiaowei

Affiliates: 1. Zhejiang Academy of Forestry, Zhejiang Key Laboratory of Biological and Chemical Utilization of Forest Resources; 2. Zhejiang Forest Products Quality Inspection Station

Source: Wood Industry Magazine, Issue 3, 2018

Abstract: A comparative analysis of the quantitative formaldehyde emissions from wood-based panels was conducted using the acetylacetone spectrophotometric method and the phenol reagent method. The results showed that, with a sampling volume of 120 L, the acetylacetone method had a detection limit of 0.007 mg/m³. However, when used to test products with formaldehyde emissions below 0.04 mg/m³, the error was relatively large, necessitating an increase in the gas flow rate or sampling time to improve accuracy. The phenol reagent method, with a detection limit of 0.0008 mg/m³, was more suitable for testing wood-based panels and their products with formaldehyde emissions below GB 18580-2017 E1 level (<0.124 mg/m³). It also exhibited high sensitivity and required a shorter sampling time.

background

my country's newly revised mandatory national standard, GB 18580-2017, "Limits of Formaldehyde Emissions from Artificial Boards and Their Products for Indoor Decorative and Renovation Materials," officially came into effect on May 1, 2018. The new standard retains only the 1 m³ climate chamber test method used in arbitration in the original standard, setting a formaldehyde emission limit of 0.124 mg/m³. Other methods, such as the desiccant method, the perforated extraction method, and the newly added gas analysis method, are only used as test methods for production quality control. The release of the new standard mandates raising the formaldehyde emission requirements for indoor decorative and renovation materials to the E1 level. The implementation of the new standard will significantly improve the environmental safety of products in the artificial board industry while also placing higher demands on formaldehyde emission detection technology.

Aiming at the detection limit of the quantitative formaldehyde emission method using the climate chamber method in the new version of the standard, the authors used the acetylacetone spectrophotometric method in GB/T 17657-2013 "Test methods for physical and chemical properties of wood-based panels and veneer wood-based panels" to conduct research, and compared it with the formaldehyde quantitative method using the phenol reagent (MBTH) method in GB/T 18204.2-2014 "Examination of hygiene methods in public places Part 2: Chemical pollutants" in order to obtain a more accurate quantitative analysis method for formaldehyde emission and provide a reference for the accurate control of formaldehyde emission from wood-based panels.

Conclusion

1) When the sample volume is 120 L, the detection limit of the acetylacetone method (10 mm pathlength cuvette) is significantly higher than the requirements of GB/T 17657-2013, making it unsuitable for determining formaldehyde emissions using a climate chamber. The detection limit of the acetylacetone method (50 mm pathlength cuvette) is slightly higher than the requirements of GB/T 17657-2013, making it unsuitable for detecting products with formaldehyde emissions below 0.04 mg/m³. If this method is the only option, it is recommended to increase the gas flow rate or sampling time appropriately.

2) The detection limit of the phenol reagent method is 0.0008 mg/m3, which meets the requirement of less than 0.005 mg/m3 in GB/T17657-2013. It is suitable for detecting products with formaldehyde emission levels lower than E1 (0.124 mg/m3) and has the advantages of high sensitivity and shortened sampling time.