1 适用范围
本标准规定了测定环境空气和固定污染源废气中三甲胺的溶液吸收-顶空/气相色谱法。本标准适用于环境空气、固定污染源无组织排放监控点空气和有组织排放废气中三甲胺的测定。若通过验证,本标准也可适用于其他挥发性脂肪胺类物质的测定。
采用氢火焰离子化检测器时,当空气采样体积为 20L(标准状态),吸收液体积为 10ml 时,方法检出限为 0.004mg/m3,测定下限为 0.016mg/m3;当废气采样体积为20L(标准状态),吸收液体积为50ml 时,方法检出限为 0.04mg/m3,测定下限为 0.16mg/m3。
采用氮磷检测器时,当空气采样体积为 20L(标准状态),吸收液体积为10ml 时,方法检出限为 0.0007mg/m3,测定下限为 0.0028mg/m3;当废气采样体积为 20L(标准状态), 吸收液体积为50ml 时,方法检出限为 0.006mg/m3,测定下限为 0.024mg/m3。
2 规范性引用文件
本标准引用了下列文件或其中的条款。凡是不注日期的引用文件,其有效版本适用于本标准。
GB 14554 恶臭污染物排放标准
GB/T 16157 固定污染源排气中颗粒物测定和气态污染物采样方法
HJ 194 环境空气质量手工监测技术规范
HJ 905 恶臭污染环境监测技术规范
HJ/T 55 大气污染物无组织排放监测技术导则
HJ/T 375 环境空气采样器技术要求及检测方法
HJ/T 397 固定源废气监测技术规范
3 方法原理
三甲胺经稀酸吸收后,将吸收液转移至顶空瓶内,处理后密封。在一定的温度条件下, 顶空瓶内样品中三甲胺向液上空间挥发,产生蒸汽压,在气液两相达到热力学动态平衡后, 气相中的三甲胺经气相色谱分离,用氢火焰离子化检测器/氮磷检测器进行检测。根据色谱峰保留时间定性,外标法定量。
4 干扰和消除
在本方法推荐的分析条件下,氨、甲胺、二甲胺、乙胺、二乙胺和三乙胺均可与三甲胺实现有效分离，不干扰测定。
名称:HH-Tamine30三甲胺毛细管柱
规格:30m*0.32mm*5.0um
使用温度:280°C
编号:20230930003
1 Scope of application
This standard specifies the solution absorption headspace/gas chromatography method for the determination of trimethylamine in ambient air and fixed source waste gas. This standard is applicable to the determination of trimethylamine in ambient air, unorganized emission monitoring point air from fixed pollution sources, and organized emission waste gas. If verified, this standard can also be applied to the determination of other volatile fatty amine substances.
When using a hydrogen flame ionization detector, when the air sampling volume is 20L (standard state) and the absorption liquid volume is 10ml, the detection limit of the method is 0.004mg/m3, and the detection limit is 0.016mg/m3; When the sampling volume of exhaust gas is 20L (standard state) and the absorption liquid volume is 50ml, the detection limit of the method is 0.04mg/m3, and the lower limit of determination is 0.16mg/m3.
When using a nitrogen phosphorus detector, when the air sampling volume is 20L (standard state) and the absorption liquid volume is 10ml, the detection limit of the method is 0.0007mg/m3, and the lower limit of the determination is 0.0028mg/m3; When the sampling volume of exhaust gas is 20L (standard state) and the absorption liquid volume is 50ml, the detection limit of the method is 0.006mg/m3, and the lower limit of determination is 0.024mg/m3.
2 Normative References
This standard references the following documents or their clauses. For undated references, their valid versions are applicable to this standard.
GB 14554 Emission Standard for Odor Pollutants
GB/T 16157 Measurement of Particulate Matter and Sampling Method for Gaseous Pollutants in Fixed Source Exhaust Gas
HJ 194 Technical Specification for Manual Monitoring of Environmental Air Quality
HJ 905 Technical Specification for Environmental Monitoring of Odor Pollution
HJ/T 55 Technical Guidelines for Monitoring Unorganized Emissions of Air Pollutants
HJ/T 375 Technical Requirements and Testing Methods for Environmental Air Samplers
HJ/T 397 Technical Specification for Fixed Source Waste Gas Monitoring
3 Method principles
After being absorbed by dilute acid, trimethylamine is transferred to a headspace bottle and sealed after treatment. Under certain temperature conditions, trimethylamine in the sample in the headspace bottle evaporates into the liquid space, generating vapor pressure. After the gas-liquid phase reaches thermodynamic dynamic equilibrium, trimethylamine in the gas phase is separated by gas chromatography and detected using a hydrogen flame ionization detector/nitrogen phosphorus detector. Qualitative analysis based on the retention time of chromatographic peaks and quantitative analysis using external standard method.
4 Interference and elimination
Under the recommended analytical conditions of this method, ammonia, methylamine, dimethylamine, ethylamine, diethylamine, and triethylamine can be effectively separated from trimethylamine without interfering with the determination.
Name: HH-Tamine30 trimethylamine capillary column
Specification: 30m * 0.32mm * 5.0um
*High operating temperature: 280 ° C
No.: 20230930003