The Environmental Protection Administration Executive Yuan announced the “Emission Standards for Hazardous Air Pollutants from Stationary Pollution Sources” (draft) in 2019. There are 72 important hazardous air pollutants planned to develop the emission standards according to a three-stage schedule. The research method is based on NIEA A807, Method 10, and Method 8270E for sampling and analytical development of Nitrobenzene, Bis(2-ethylhexyl)phthalate, Hexachloroethane, Benzidine, 4,4'-Methylenebis(2-chloroaniline), Hexachlorobenzene, Polychlorinated biphenyl (PCBs) and Polycyclic aromatic hydrocarbons (PAHs).
The project aims to establish appropriate survey technology of the aforementioned pollutants, and the factors of collection efficiency, chromatography instrument optimization analysis conditions, applicable concentration range, storage conditions, and possible interference and removal methods caused by moisture, etc. should be considered. And then the research must be evaluated according to the "Environmental Testing Standard Method Verification Procedures Guidelines" set by the Environmental Analysis Laboratory, EPA. In the final report, the draft of development of sampling and analytical methods for semi-volatile organic compounds in stacks must be proposed, and that meets the specifications of the method format.
In the beginning, six analyte including Nitrobenzene, Bis(2-ethylhexyl)phthalate, Hexachloroethane, Hexachlorobenzene, PCBs and PAHs were tested by GC/MS/MS with reference to the NIEA M731 method. The calibration curve was verified by internal standard, and the results show that the relative standard deviation (RSD %) complies with the technically acceptable requirements of the method (<30%). Nevertheless, the results of method detection limit compared with the project's estimated emission standards, showing that all compounds meet the requirements of the regulatory standards. The method could achieve expectation of method establishment.
Benzidine and 4,4'-Methylenebis(2-chloroaniline) (MOCA) were analyzed by LC/MS/MS. Regarding calibration curve, the correlation coefficient R of linear regression exceeded 0.999. The result of method detection limit compared with the project's estimated emission standards, showing that both compounds meet the requirements of the regulatory standards. The method could achieve expectation of method establishment
In sampling compounds, referring to NIEA A801 method, Nitrobenzene, Bis(2-ethylhexyl)phthalate, Hexachloroethane, Hexachlorobenzene, PCBs and PAHs sampled by 60 g adsorbent XAD2. However, in sampling process meet big trouble with pressure loss. The project get great condition with 30 g adsorbent and flow rate 0.125 m3/min. The method of sampling compounds Benzidine and MOCA referring to CLA 2101 and NIEA A705. Using Methanol with 0.17 % Triethylamine as absorbent had great recovery rate.
There are 4 samplings of stacks in the domestic factory completed. The result showed that sampling and analysis condition were available. Besides, two sessions of technological diffusion were held in August and October 2020 respectively. In conclusion, the draft program of sampling and analytical methods for semi-volatile organic compounds in stacks is proposed to provide future reference of the detection technology.