Why NIR is better than a GC?
NIR (Near-Infrared) analyzers and Gas Chromatography (GC) are both analytical techniques used for chemical analysis, but they differ in their underlying principles and applications. NIR analyzers use the absorption of light in the near-infrared region of the electromagnetic spectrum to determine the chemical composition of a sample. This technique is non-destructive and requires little to no sample preparation, making it a rapid and efficient method for analyzing a wide range of samples. NIR is widely used in the food, agricultural, and pharmaceutical industries for quality control and process monitoring.
On the other hand, GC is a chromatography technique that separates and analyzes volatile and semi-volatile organic compounds. The sample is vaporized and then passed through a chromatographic column, where the individual components are separated based on their physical and chemical properties. GC is a highly sensitive technique and can provide very precise and accurate quantitative data. It is often used in environmental analysis, forensic science, and drug discovery.
The choice of which technique to use depends on the specific analytical needs of the user. However, in general, NIR analyzers can be considered better than GC for certain applications, such as:
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Non-destructive analysis: NIR can analyze samples without destroying them, whereas GC requires the sample to be vaporized, which can lead to sample loss or alteration.
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Speed: NIR can provide rapid results, often in a matter of seconds, whereas GC requires a longer analysis time.
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Ease of use: NIR is a relatively simple and user-friendly technique, requiring little to no technical expertise, while GC requires specialized training and expertise.
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Broad applicability: NIR can be used for a wide range of samples, including solids, liquids, and gases, whereas GC is typically limited to volatile and semi-volatile organic compounds.
NOTE: GC analyses can have significant annual costs associated with routine maintenance, column degradation, and carrier gas consumption. Such continual costs can be greatly reduced by replacing with a Guided Wave inline spectrometer-based analyzer
Process NIR
- Very Fast, Real-Time, Online Monitoring
- Instant Optical Separation of Components
- Solvent Recovery – measures mixtures of different solvents
- Measures chemical concentrations 0.1%, or greater, for dissimilar materials
- Can quickly measure moisture in solvents (high % to low ppm concentrations)
- Functional Group Differentiation (methyl vs. methylene, aromatic vs. aliphatic, etc.)
- Excellent Performance Property Predictions (octane number, vapor pressure, viscosity, density, flash & cloud point, cetane index)
- Good for Product Quality Parameters
- Low Maintenance
Process GC
- Fast, Near-Time, At-line Monitoring
- Time-based Flow Separation in Columns
- Specific chemical analysis of very similar structures
- GC better for trace analysis and environmental analysis
- Best for gas analysis in low concentrations
- Fixed gases such as air, CO, CO2, NOx, H2
- Some performance prediction abilities (calorific value of natural gas)
- Good for Trace Impurities in Products
- Fuel Sulfur, Simulated Distillation
- Routine Maintenance and regular Consumables costs
