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Near Infrared & UV/VIS Spectroscopy Technology

near infrared and UV-VIS spectroscopy Technology

Near Infrared (NIR) and Ultraviolet / Visible (UV-VIS) spectroscopy are two common types of spectroscopic techniques used in analytical chemistry and other scientific fields.

NIR spectroscopy is a non-destructive analytical technique that involves the interaction of near-infrared radiation with a sample. The NIR region of the electromagnetic spectrum is located between the visible and mid-infrared regions, and typically ranges from 780 to 2500 nanometers. NIR spectroscopy is used to identify and quantify the presence of different chemical components in a sample, such as moisture, protein, fat, and sugar content in food and agricultural products.

UV-VIS spectroscopy is another non-destructive analytical technique that measures the absorption, transmission or reflectance of ultraviolet and visible light by a sample. The UV region ranges from 200 to 400 nanometers, and the visible region ranges from 400 to 700 nanometers. UV-VIS spectroscopy is commonly used to determine the concentration of a compound in a solution, as well as to characterize electronic and structural properties of molecules.

Powerful Near Infrared (NIR) and Ultraviolet / Visible (UV-VIS) spectroscopic techniques are used in our GUIDED WAVE™ NIR & UV-VIS Process & Lab Analyzers and optical solutions. We deliver a total solution that includes optically matched components and a well-planned calibration approach leading to long-term success and savings. Our state-of-the-art systems are designed for continuous online use, providing real-time data of laboratory quality while thriving in the most demanding processing plant environments. These analyzers are adaptive in nature; meaning that the analyzer can be programmed to measure many different parameters related to many different processes.

Our full-spectrum, extended-range, near-infrared process spectrometer (XNIR, 1000-2100 nm) for a wider range of applications monitor in real-time, in-process measurements for fast, reliable online analysis and monitoring of complex process streams.  The dual-beam design to maximize long-term stability and in-process robustness.  





Optical Absorption Spectroscopy Process & Lab Analyzer Solutions

Optical Absorption Spectroscopy Process & Lab Analyzers

APPLICATIONS OVERVIEW FOR NIR VIS UV ANALYZERS

Key WordIndustryApplication TitleDescription
APHAPetroleumOn-Line Monitoring of APHA ColorAPHA is sometimes referred to as the Platinum- Cobalt (Pt/Co) or Hazen scale. Also referred to as a “yellowness index”, the APHA color scale is a common method of comparison of the intensity of yellow-tinted samples to assess the quality of liquids that are clear to yellowish in color. Discover how real-time monitoring of APHA color either on-line or in a laboratory setting using a photometer can improve your process.
Aromatics

PetroleumMonitoring the Percent Aromatics in Gasoline by NIRThe aromatic content of gasoline determines many of its combustion properties. Since it also impacts the environmental characteristics of the fuel it is desirable to have accurate measurements of this parameter. The traditional analytical method for measuring aromatics is either gas chromatography (GC) or an older method entitled fluorescent indicator adsorption (FIA), both of which are time and labor intensive. Learn how Guided Wave hardware and software can provide real-time measurement of % aromatics in fuel products using fiber optic-based, Near-Infrared (NIR) spectroscopy.
ASTM Color / D1500 / D1524
PetroleumOn-line Monitoring of ASTM Color (0-7) With a ClearView® db PhotometerASTM color (reference ASTM D1500, ASTM D1524) describes the color measurement method for fuels including lubricating oils, heating oils, diesel fuels, and petroleum waxes. The lowest value of 0.5 being a light yellow, 2 being yellow, 5 being orange, and 8 being a deep red. ASTM color is an important product quality measurement for many refinery and petrochemical processes.
BenzenePetroleumBenzene in Gasoline

The NIR spectra of a group of 150 different process gasoline samples with known benzene concentration ranging from 0.2 to 6.0% were measured between 1000 and 1600 nm using a GUIDED WAVE NIR Spectrometer. NIR is a time and money saving alternative to traditional methods.
Cetane NumberPetroleumCetane Number of Diesel FuelsThe Cetane number of a diesel fuel is a measure of the ignition properties and is an important specification that must be met during fuel production. The traditional laboratory method for Cetane number determination is the knock engine method in which the fuel is burned and its combustion characteristics compared to known standards. This method is time and labor intensive, and provides no ability for real-time control of production. This note discusses the use of GUIDED WAVE hardware and software for the measurement of Cetane number in diesel fuel using fiber optic-based, Near-Infrared (NIR) spectroscopy.
StyreneChemicalOn-Line Control of a Styrene TowerA ClearView db Photometer was installed at a Styrene production tower to monitor the concentration of styrene in ethylbenzene in the presence of toluene and benzene. The MLR calibration for styrene in 10 overhead samples resulted in an (R2>.9999) with a standard error of 0.84% styrene.
Ethylene DichlorideChemicalSafe Operation of your EDC ReactorEthylene dichloride (EDC) plants need to monitor the ethylene content in the vent gas. By using Near Infrared Spectroscopy, the control systems can maintain a constant concentration in the vent gas and also ensure that the concentration is maintained at safe levels during start-up.
Caustic & CarbonateChemicalOn-Line Monitoring of Caustic & CarbonateLearn about the simultaneous measurement of caustic (NaOH) and sodium carbonate in aqueous process streams, particularly at low (<2%) caustic concentrations, using a ClearView db NIR photometer and fiber optic probe.
AtrazineChemicalMonitoring Triazines and their PrecursorsLearn about the measurement of various triazines using fiber optic-based, UV-Vis spectroscopy. Atrazine is a common contaminant in ground and surface water where it is slow to degrade. Agricultural runoff is the major source of surface water contamination. The US EPA Maximum Containment Level Goal (MCLG) for drinking water is 3ppb.
Trubidity / HazePetroleumOn-Line Monitoring of Turbidity or HazeAlongside the measurement of Color, Turbidity is a property of interest for monitoring the quality of a fuel. Learn how Guided Wave has developed a Color and Turbidity monitor which is directly compliant with ASTM method D4176.
Fuel BlendingPetroleumContinuous Fuel Identification for PipelinesReliable, affordable, real-time identification of petroleum products flowing in pipelines can enable terminals to identify the ideal time (t90) to switch to the correct storage vessel. This helps to minimize waste and the need for reprocessing petroleum products.
OctanePetroleumRealtime Octane Number DeterminationThe Octane number rating of a gasoline is an indication of how the gasoline will perform under various engine conditions. Two different ratings are included: Research Octane Number (RON) and Motor Octane Number (MON). Finished gasoline must meet certain Octane number specifications. Thus refineries control this parameter during production and must certify that a gasoline meets specification before it is released. Learn how Guided Wave can help ensure proper Octance levels avoiding the delay of an engine knock test.
LNGPetroleumColor in LNG (liquefied natural gas)Measuring the Saybolt or ASTM color online is a key parameter in many light hydrocarbon mixes, such as Liquid Natural Gas for quality control. Monitoring the color allows the refiner to verify that the product is within specification and identify any “out of spec” product for reprocessing before being sold.
SayboltPetroleumOn-Line Monitoring of Saybolt ColorSaybolt color (reference ASTM D156, ASTMD6045) is primarily used in characterizing fuels including automobile and aviation gasolines, jet fuel, diesel fuel and other petroleum products. The Saybolt color scale goes from 30, which a barely perceivable yellow, to –16 which is a definite yellow. Learn how Guided Wave can provide cost-effective, explosion proof, field ready Saybolt Color monitors.
IodinePetroleumIodine Value of OilsAn important characteristic of a fatty oil product is its iodine value (IV). This is a measure of the unsaturated fatty acid content and indicates the ease of oxidation or the drying capacity of the product. Empirically, the IV is expressed in terms of the number of centigrams of iodine per gram of sample. Learn how NIR can be applied in real time to directly monitor your process.
Ethylene GlycolsChemicalOn-Line Monitoring of Water in Ethylene GlycolsConcentrations ranging from 0-100% water in Ethylene Glycol, each at 20, 25, 30, 35, 40 and 45°C were scanned on a NIR-O Full Spectrum Analyzer. A four-wavelength multiple linear regression was performed, which resulted in excellent linearity (R2>.9999)
Dimethylformamide / DMFChemicalOn-Line Monitoring of Water in DimethylformamideThe ability to monitor low levels of water in dimethylformamide (DMF) is a key consideration in the production of 1,3 butadiene. The quality of the final product (purity) can be compromised when water in excess of 400ppm is present in the DMF solvent stream. NIR spectroscopy provides the ideal method for in-situ water measurement.
PolyurethaneChemicalMeasurements in Polyurethanes In SituMany aspects of polyurethane production such as isocyanate concentration can be measured using Near-infrared (NIR) spectroscopy. In situ monitoring in the reactor systems allows for control of important properties during the reaction and to determine the endpoint of the reaction, thus adding to the value and cost savings.
Polymer Resin Reaction EndpointChemicalDetermining Polymer / Resin Reaction Endpoint In SituDetermining reaction endpoint in polymer/resin reactors is critical to achieve desired product properties, such as molecular weight. Knowing exactly when the reaction is over saves residence time and batch conversion time, and lowers the overall manufacturing cost. Learn how GUIDED WAVE can help save you time and money with in-situ reaction monitoring and spectroscopy based reaction endpoint monitoring.
Ethanol
PetroleumReal-time Determination of Ethanol in GasolineEthanol is now a common biofuel additive for gasoline. The additional oxygen in ethanol provides for a cleaner burning fuel. The data presented demonstrates the measurement of the ethanol content of fuel using near-infrared (NIR) spectroscopy.
Fuel IDPetroleumProduct Pipeline Interface Detection by NIR SpectroscopyPetroleum product pipelines provide an efficient method of delivering product to distribution terminals. These multi-purpose pipelines deliver many different fuels often injected into the pipeline in a sequential fashion with no physical barriers between products. The receiving terminal must detect and separate the products in order to send them to the appropriate tanks and also identify off-specification product.
Polymer MeltsChemicalOnline Monitoring of Polymer Melts Using UV Fiber-Optic SpectroscopyPolymer performance is directly related to the level of stabilizer. As a result, measurement and control of the additive concentration that is melt compounded into the polymer is crucial. Making these measurements in the melt offers many advantages over current offline quality control methods such as gas chromatography (GC) and high-performance liquid chromatography (HPLC). This application note will discuss an online UV/VIS method for monitoring the levels of hindered phenols and phosphites in polypropylene.
AcroleinChemicalSafe and Efficient Control of the Acrolein ProcessAcrolein (or propenal) is the simplest unsaturated aldehyde. It is a colorless liquid and is mainly used as a biocide or as a building block to other chemical compounds. Measurement of both the water and acetaldehyde concentration in the final product is required. Acrolein is toxic and, without online analysis, hazardous manual sampling will be needed. Near-infrared spectroscopy can provide rapid, real-time, in-situ analysis of the Acrolein cross-linking process.
Cloud PointPetroleumCloud Point of Diesel FuelThe Cloud Point of a diesel fuel is the temperature below which wax forms giving the fuel a cloudy appearance. This parameter is an important property of the fuel since the presence of solidified waxes can clog filters and negatively impact engine performance. The traditional laboratory methods for the measurement of Cloud Point are optical in nature, but rely on cooling the fuel for the wax formation to occur. Guided Wave’s NIR instrumentation can measure composition changes in the fuel that will be directly related to the wax formation and hence the Cloud Point.
Hydroxyl and Acid NumbersChemicalHydroxyl and Acid Numbers in Resin MeltsLearn how to monitor your hydroxyl and acid numbers online in resin melt and determine what the process yield will be. Alternatively, monitor your reaction to determine the end of reaction across multiple products.
WaterChemicalA Word (or Two) About Online NIR Water Measurements in Liquid SamplesWater is perhaps the most common measurement made in the near-infrared (NIR). This is due to its strong effect on product properties and chemical reactivity of the starting materials. Learn some useful facts to consider when monitoring aqueous solutions with near-infrared spectroscopy.
SaccharinChemicalMonitoring breakthrough of Low Level Organics in WaterSaccharin is used as a sweetener and preservative in pharmaceuticals, nutraceuticals, and food and as an agent in semiconductor plating baths. Molecules similar to saccharin, i.e. benzo substituted heterocyclic rings, are used in semiconductor cleaning solutions. These applications often require control of organic concentrations in water in the 100 ppm range and below. Using Saccharin as a model trace contaminant learn how NIR can be used to identify when levels warrant replacement of the filter or reaction bath.
Phosphoric Acid
SemiconductorAutomated Determination of Phosphoric Acid ConcentrationThe use of phosphoric acid solutions is common in the semiconductor industry to both clean and etch metal surfaces. The concentration of the phosphoric acid is important to optimize these processes. Typically the laboratory method used for this determination involves one or more titrations. Learn how spectroscopy can be used for online in-situ monitoring of Phosphoric Acid Concentration.
SolventsChemicalMonitoring Water In SolventsWater can be detected at much lower levels in non-OH containing solvents since there is less interaction between the base solvent and the water. However, in OH containing solvents such as Methanol, water can be detected down to several hundred parts per million. The measurement of the water levels in solvents with NIR spectroscopy is both fast and reliable utilizing the Guided Wave hardware and produces results that are available in real-time (seconds) thus making it a valuable tool for process measurement.
BenzotriazoleSemiconductorAutomated Monitoring of Benzotriazole Contamination For the Semiconductor IndustryBenzotriazoles have many uses. They can be used in the semiconductor industry in wafer cleaning, an anti-freeze ingredient for de-icing airplanes, in photographic developing baths, as a corrosion inhibitor for copper and bronze, a UV stabilizer in some plastics, and as a precursor for many pharmaceutical compounds. Though benzotriazoles are readily water-soluble they are not significantly biodegradable or readily removed by common water treatment methods. UV spectroscopy is a useful method for online monitoring of wastewater for benzotriazoles contamination.
Tetramethylammonium HydroxideSemiconductorAutomated Determination of Tetramethylammonium Hydroxide in WaterFor semiconductor wafer processing, the level of tetramethylammonium hydroxide in water is very critical in the developer blend system. The solution of tetramethylammonium hydroxide must be kept at 2.38%. The concentrations of tetramethylammonium hydroxide can be easily measured at 2.38% by near-infrared (NIR) spectroscopy with a Guided Wave fiber optic coupled NIR-OTM Process Analyzer to better than ±0.1 % v/v. Analysis time is under 50 seconds.
Hydroxyl NumberChemicalHydroxyl Number in PolyolsThe use of polymeric polyols is commonplace in the manufacturing of polyurethanes and other specialty polymers. The hydroxyl number (OH#) is a measure of the concentration of the hydroxyl groups on the polyol. This is an important parameter to monitor and control during polyol production. Learn how NIR can be used for real-time monitoring of Hydroxy Number of polyol cross-linking reactions.
Binary Solvent Feed Mixtures for Liquid ChromatographyPharmaceutical Binary Solvent Mixtures for High-Performance Liquid ChromatographyDiscover the comprehensive analytics capabilities of NIR for ensuring proper mixture ratios of analyte samples being injected into HPLC columns. The correct mixture ratio ensures efficient and correct separation of the chemical targeted for separation in pharmaceutical applications.
HPLC Binary Solvent Feed MixturesChemicalFast Online Analysis of HPLC Binary Solvent Feed MixturesBinary solvent mixtures are used as carriers in production scale pharmaceutical HPLC separations. Analysis of the mixture ratios is required prior to injection into the HPLC column. The correct mixture ratio ensures efficient and correct separation of the chemical targeted for separation. Learn how this can be achieved with NIR.
Ethylene Oxide / EOSterilization and Virus DeactivationOn-Line Monitoring of Ethylene Oxide SterilizationNear Infrared Spectroscopy provides real-time measurement of ethylene oxide (EO) gas during sterilization cycles. Ideal for use in sterilizer applications, this technology provides real-time results to ensure method compliance.
Epoxy ValueChemicalOn-Line Monitoring of Epoxy ValueReal-time monitoring of the Epoxy Value enables you to see into the reaction and monitor the epoxide group content and ensure that proper cross-linking is occurring.
Hydrocarbon Gas StreamsChemicalOnline Monitoring of Hydrocarbon Gas StreamsA common concern of hydrocarbon vapors, especially in ambient air mixtures, is the concentration relative to the Lower Explosion Limit (LEL). GUIDED WAVE'S NIR instrumentation can make both qualitative and quantitative measurements in gas streams using long path gas cells coupled to our analyzer systems to monitor short-chain alkanes such as Butane.
AcetonitrilePharmaceuticalMonitoring Reverse Phase LC of Acetonitrile/Water in Pharma ApplicationsA ClearView db Photometer was used to monitor the Acetonitrile (ACN):water mobile phase gradients for the chromatographic separation of active Pharmaceutical ingredients.
Alcohol Brine SolutionsChemicalReal-time Water Analysis in an Alcohol-Brine SolutionThis application note indicates that a ClearView db fiber optic filter photometer with an analyzing wavelength of 1820 nm and a reference wavelength near 1050 nm can analyze water in the presence of alcohols and salt.
Acetic Acid-p-xylene
ChemicalMonitoring Water in Acetic Acid & p-XyleneWater can be analyzed near 1380 nm, independent of p-xylene or acetic acid content. Multiple linear regression (MLR) system- atically investigates which wavelength or wavelengths provide a statistically acceptable calibration. The MLR results confirmed that water can be determined solely at 1390 nm, and that acetic acid and p-xylene can be determined using two wavelengths at 1140 and 1380 nm.
AcetoneChemicalMonitoring Water in Aromatic/Acetone MixturesSamples containing isopropyl benzene, acetone and phenol in approximately constant ratios were measured with a NIR Spectrophotometer. It was found that water in complex mixtures can be measured with an accuracy better than ±0.01% (wt.). Moreover, the spectrophotometer can utilize multiple fiber optic insertion probes flanged directly into a reactor or column, or flow cells on a slip stream for improved cost per sample point.
Trazines ChemicalMonitoring Trazines and their Precursors In Agricultural RunoffAgricultural runoff is the major source of surface water contamination. The US EPA Maximum Containment Level Goal (MCLG) for drinking water is 3ppb. The UV-Vis region of the electromagnetic spectrum displays electronic transitions and is particularly useful for viewing conjugated and aromatic molecules. By measuring the UV spectra of a series of samples of known atrazine or atrazine derivative concentration, a quantitative model can be developed which will allow the measurement of future samples based only on their UV spectrum.
Liquefied Natural Gas / LNGPetroleumDetecting Various Levels of Color of LNG with High Accuracy per ASTM Method D156, D6045A GUIDED WAVE Saybolt Color Analyzer System was fully implemented for real-time color measurement of various grades of LNG (liquefied natural gas) product with multiple specification requirements. Since the GUIDED WAVEcustomer required the measurement of various grades of LNG, they could not use just a “go” or “no-go” color analyzer. They needed to find an analyzer that was able to detect varying levels of color with a high degree of accuracy in accordance with ASTM D156 and ASTM D6045.
Fertilizer / Nitrous Acid (HNO2)
ChemicalNitrous Acid (HNO2) Measurement in Fertilization PlantGUIDED WAVE’S dual-beam ClearView® db Vis-NIR Process System Analyzer was fully incorporated for plant-wide HNO2 measurement and optimization. A global firm specializing in agricultural products and environmental protection agents needed a solution to improve employee safety during the manufacturing process. After researching several technologies to measure HNO2 in the lab, they determined that GUIDED WAVE'S ClearView db Analyzer System was the best solution.
Caustics in WaterChemicalCaustic in Water with a ClearView db Filter PhotometerMeasuring NaOH concentration in water on-line with the ClearView® db filter photometer and a fiber optic flow cell in a slip stream.
RON / Research Octane NumberPetroleumRON / Research Octane Number A GUIDED WAVE dual-beam NIR Process Analyzer System was fully incorporated to measure Research Octane Number (RON) of reformate from a plant’s catalytic reformer. Accurate real-time measurement saved the company money in additional, unexpected ways.
Jet Fuel
PetrochemicalJet FuelJet fuel quality parameters such as Cetane Index(#), API Gravity, Viscosity, Aromatics, and Distillation (D10, DS0, etc) are all good candidates for measurement by NIR spectroscopy.
TMAH in WaterChemicalTMAH in Water
Polymer MeltsChemicalNIR UV in Polymer Melts
Water in SolventsChemicalWater in Solvents
Water in DMFChemicalWater in DMF
Water in Liquid SamplesChemicalNIR Water Measure in Liquid Samples
Water in Alcohol BrineChemicalWater in Alcohol Brine
Water Aromatics Acetone MixChemicalWater Aromatics Acetone Mix
LNG (Saybolt) ASTM D156, D6045PetrochemicalDetecting Various Levels of Color (Saybolt) for LNG
Saybolt Success Story; ASTM D156, D6045
Sulfuric Acid ConcentrationChemicalSulfuric Acid Concentration with ClearView db Photometer
ASTM D1500Petrochemicaldetermine ASTM (D1500) color with our cost-effective GUIDED WAVE ™ ClearView® db Dual Beam Fiber Optic Photometer.ASTM color (reference ASTM D1500, ASTM D1524) describes the color measurement method for fuels including lubricating oils, heating oils, diesel fuels, and petroleum waxes.
Trace Copper ContaminationSemiconductorDetecting Trace Copper Contamination in Electroplating Solutions (Trace Cu Detection in Acidic Silver/Tin Solutions)Copper contamination is a major concern for the semiconductor industry. With the advent of Tin and Tin/Silver solders for Lead-Free/RoHS compliant electrodeposition, the risk of trace copper contamination (<20 ppm) due to leaching of copper into the acidic bath solutions requires real time monitoring to ensure proper plating.
Clearning SolutionsSemiconductorMonitor Cleaning Solutions in Semiconductor Wafer Manufacturing ProcessOne major challenge in operating wet chemical cleaning processes is maintaining optimal bath conditions required for uniform cleaning, reduced cycle times and minimal product rework. As an added benefit, accurate analysis of bath conditions makes the most efficient use of costly ultra-pure chemicals, and reduces chemical waste. Learn how a ClearView db photometer can be used to Monitor Cleaning Solutions in Semiconductor Wafer Manufacturing Processes.
Hydrogen PeroxidePharmaceutical Online monitoring of Hydrogen Peroxide SterilizationGUIDED WAVE'S HPV analyzer is a simple turnkey solution for the measurement of hydrogen peroxide and water (H202) concentrations in vapor phase. These are both measured together because they are codependent. The analyzer operates in real time, which takes the guesswork out of determining the H202 concentrations during cycle development and throughout the actual sterilization cycle.
Styrene Acrylonitrile SAN CopolymerChemicalOnline Process Monitoring of Styrene / Acrylonitrile / MEK (SAN Copolymer)Proof of concept study for monitoring the concentration of styrene, acrylonitrile, and mek concentrations during the copolymerization of SAN.
Whole Room Vaporized Hydrogen Peroxide MonitoringSterilization and Virus DeactivationAdapting NIR Technology for Whole Room SterilizationVaporized Hydrogen Peroxide can be monitored in sterile fill isolator areas and rooms used for biological experiments (Biosafety Level 3 and 4 rated labs) require periodic decontamination and virus deactivation. This application note demonstrates a successful installation at The National Cancer Institute (NIH) Research and Production Center at Ft. Detrick, Maryland.
Color in Refined FuelsPetrochemicalMeasuring Color in Refined Fuels
Polyester (PET) SynthesisChemicalNear-Infrared Analyzers for Polyester (PET) SynthesisInfographic that show cases various locations in Polyester (PET) that can benefit from NIR monitoring.
Polymerization and Nucleation rate, Crystallization growth rate, Particle SizeChemicalRelating Particle Size and Turbidity With a ClearView dbParticle size information can be directly estimated because the ClearView db is capable of measuring the forward scattering at visible and near infrared wavelengths, and sideways scatter from the wide bandpass turbidity filter. The measurement of forward scattering at higher wavelengths allows for larger (>200 micron diameter) particles to be measured. The dual measurement allows for a customizable turbidity measurement
NIR Analyzers for Polyurethane SynthesisChemicalNIR Analyzers for Polyurethane SynthesisInfographic that show cases various locations in Polyurethane Synthesis that can benefit from NIR monitoring
Viscosity in Polyurethane Polymer
ChemicalViscosity in Polyurethane Polymer
Crude Oil ProcessingPetrochemicalCrude Oil Processing
Dual Probe Polyurethane SynthesisChemicalCombining Process Rheology & Spectroscopy Measurements to Improve Batch Polyurethane Polymer ProductionThe control logic shown can be adapted as needed to meet the specific product requirements. During the first step, process spectroscopy is used to monitor the monomer conversion and weight average molecular weight.

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