01 Solution Summary
A surface water sample is placed in a sealed headspace vial to establish gas-liquid or gas-solid equilibrium, and the gas phase in the vial is taken into the GC to determine benzene series compounds such as benzene, toluene, ethylbenzene, and xylene. The following arrangements are used for quantitation and quality control: for benzene series compounds such as benzene, toluene, ethylbenzene, and xylene, use reference materials matched to the detection channel to establish a calibration relationship; the identification basis, quantitation mode, and result units are all subject to the applicable method; blanks, calibration checks, duplicate samples, and quality control samples form batch quality control. Analytical batches are also set up with blanks, calibration checks, and applicable quality control samples.
02 Standards and Method Basis
Method basis: application method. The laboratory may enter the name and version of the adopted formal method into the project file.
03 Samples and Analytes
The specific samples areSurface water samples, and the analytes areBTEX compounds such as benzene, toluene, ethylbenzene, and xylene. Pretreatment, injection, and detection configurations are determined according to the sample state, target concentration, and the formal method adopted.
04 Method Principle
Volatile components in a sealed headspace vial reach reproducible partitioning between the sample phase and the gas phase; the automatic headspace system samples from the gas phase and transfers it to the GC.
This workflow centers on the equilibration and gas-phase transfer of volatile components, and the detection unit is a detector selected according to the target analyte response.
05 Sample Collection and Pretreatment
Weigh or measure the surface water sample into a clean headspace vial, add matrix adjustment components according to the official method used, and seal immediately. Sample vials, blank vials, and standard vials use the same equilibration and injection procedure.
06 Separation and Detection
Headspace gas enters the GC through the transfer line, the column separates BTEX compounds such as benzene, toluene, ethylbenzene, and xylene, and a detector selected according to the target analyte response acquires the response.
07 Instrument System Configuration
| Module | Configuration | Role in This Solution |
|---|---|---|
| Sample container | Sealed headspace vial and sealing components | Establish a closed equilibrium system |
| Headspace sampler | Thermostatting, shaking, and gas-phase sampling | Transfer volatile components |
| GC system | GC | Complete the separation of volatile components |
| Detection Unit | Detector selected according to target analyte response | Acquire target analyte responses |
08 Huishi Instruments system configuration
This application requiresGas chromatography (GC) analysis systemComplete the analysis of benzene series compounds such as benzene, toluene, ethylbenzene, and xylene. During configuration selection, the sample introduction interface, detector, and data system should be determined based on the sample state of the surface water sample, headspace gas-phase quantitative injection, and detection requirements.
09 Analysis workflow
10 Qualitative, Quantitative, and Quality Control
Calibration relationships are established around BTEX compounds such as benzene, toluene, ethylbenzene, and xylene using reference materials matched to the detection channel; the qualitative basis, quantification mode, and result units are all subject to the applicable method. Blanks, calibration checks, parallel samples, and QC samples form batch quality control. Blank headspace vials, parallel vials, calibration checks, and vial-to-vial repeatability are used to monitor the headspace process.
11 Method and Configuration Selection
- The sample must be suitable for achieving reproducible gas-phase partitioning in a sealed vial.
- The equilibration procedure, vial volume, and sampling mode are kept consistent between calibration and samples.
12 Frequently Asked Questions
Why use headspace-GC for BTEX compounds such as benzene, toluene, ethylbenzene, and xylene?
Headspace-GC matches the physicochemical properties, sample inlet, and detection objectives of benzene series compounds such as benzene, toluene, ethylbenzene, and xylene; the complete workflow also covers the treatment, separation, detection, and data quality control of surface water samples.
What samples is this solution applicable to?
The applicable samples are surface water samples. When the sample source or matrix changes, the effects of co-existing components on pretreatment, separation, and detection response should be re-evaluated.
What components or indicators are included in the detection targets?
The analytes are benzene, toluene, ethylbenzene, xylene, and other benzene series compounds; both the main text and configuration are bounded by this entity scope.
How is quality controlled for an analytical batch?
For each batch of samples, set up method blanks, calibration verification, duplicate samples, or applicable QC samples, and retain records of sample processing, instrument conditions, calibration, and calculations.
What information is required before configuration?
It is recommended to provide real samples, a list of target compounds, expected concentration ranges, testing batch size, the method to be followed, and existing equipment conditions.
How are results kept traceable?
Sample numbers, reference materials, processing batches, instrument methods, raw data, calibration results, and review records together form the result traceability chain.
Why is headspace vial sealing important?
The sealing state directly affects the partitioning of volatile components between the sample phase and the gas phase and the injection repeatability.
13 Related Solutions and Knowledge
Get Configuration and Technical Consultation
Please provide the sample information for the surface water samples, the concentration ranges of benzene series compounds such as benzene, toluene, ethylbenzene, and xylene, the testing batch size, the method basis, and the existing equipment. Huishi Instruments will then prepare a configuration list based on this information.
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