Application Finder

Harmful industrial flue gases like H2S and CO2 cause corrosion of pipes and damage the environment. Adding the correct amount of amines in scrubber solutions, e.g. ethanolamines and methylamines, will neutralize these gases («gas sweetening»). Non-suppressed cation analysis with direct conductivity detection is a straightforward and robust technique for the quantification of monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), monomethylamine (MMA), dimethylamine (DMA), and trimethylamine (TMA) via ion chromatography. Thanks to the high capacity of the Metrosep C 6 column, large volumes can be injected without compromising the peak shapes. The analytical technique can be used at laboratory scale but also for process analysis.

During polymerization, real-time determination of hydroxyl and acid numbers of polyols provide important information about molecular weight and the reaction end point. This Application Note sheds light on the practical aspects of process monitoring in a polyol batch process using NIRS methodology. Real-time process monitoring with NIRS is the key to lower production costs and better product quality.

This Application Note describes how NIR spectroscopy can be used to determine residual lignin content in wood pulp. Using the major absorbance peaks of both lignin and cellulose in the second derivative spectra, the residual lignin content in wood pulp can be monitored during paper production.

This Application Note describes an NIR method for monitoring the esterification process in butyl acetate production. The developed NIR method shows excellent analytical performance equivalent to that obtainable with more time-consuming GC methods.

Well-mixed active substances for medications are indispensable in the pharmaceutical industry. This applies not only to the pharmaceutical active ingredient but also for lubricants, binding agents, explosives, oxidants and dyes. Analysis of these active ingredients is expensive; they are also only rarely analyzed as a rule. The progress of the mixing procedures can be followed conveniently with NIR spectroscopy, on the one hand using visual comparisons and on the other by means of spectral algorithms. The progress of mixing processes can be predicted in real time with the help of the spectrum when the latter is used.

This Application Note describes the utilization possibilities of a new sensor design that permits, in combination with an NIRS XDS Process Analyzer, the determination of solvent residues in a High-Shear Granulator during the drying phase. This system configuration reduces the scattering of the density distribution of the powder samples so that it is possible, directly in the process, to model the water and solvent content precisely.

This Process Application Note details the simultaneous online analysis of H2S and NH3 in sour water which was previously treated in the sour water stripper (SWS). The method includes automatic cleaning and calibration. Fast and accurate results are continuously supplied for process control.

Gold leaching by cyanidation requires precise monitoring of cyanide and gold. Online process analyzers perform such measurements, improving safety and compliance.

Carbon capture systems strip carbon dioxide from flue gases. Online analysis of amines and carbon dioxide enhances amine usage efficiency and reduces operational costs.

The Kraft process is the dominant pulping process in the pulp and paper industry with the highest chemical recovery efficiency. In order to run each part of the papermaking process optimally, constant quality checks and analyses should be performed. This Process Application Note illustrates the straightforward online analysis of alkali (active, effective, total titratable alkali (TTA)), carbonate, hydroxide, sulfide and the causticizing degree (CE%) in pulping liquors using a 2060 Process Analyzer from Metrohm Process Analytics.

In this Process Application Note, the analysis of low concentrations of calcium and magnesium (0–20 µg/L) in brine is addressed. The presence of calcium and magnesium can shorten the performance and lifetime of the membranes used in the chlor-alkali industry for the production of chlorine. Accurate online monitoring of the hardness is needed in several stages of the process. Other parameters such as acidity, carbonate, hydroxide, silica, alumina, ammonia, iodate and chlorine can also be analyzed online.

This Process Application Note is dedicated to the online analysis of zinc, iron and sulfuric acid in several stages of the zinc production process. Additionally, traces of germanium, antimony, as well as several transition metals (e.g., Ni, Co, Cu, Cd) can be precisely determined (<50 µg/L) in the purification filtrates and reactor trains.

In the HPPO – hydrogen peroxide to propylene oxide – process for propylene oxide production, hydrogen peroxide is analyzed using a complexing agent and a colorimetric measurement with dipping probe. Due to the hazardous environment, the online analyzer fulfills EU Directives 94/9/EC (ATEX95) and is certified for zone1 and zone2 areas.

In the cumene process, phenol and acetone are produced from benzene and propylene. For a successful process control, it is crucial to monitor the sulfuric acid concentration, which impacts the acid-catalyzed cleavage of cumene hydroperoxide to yield phenol and acetone. This Process Application Note describes the online analysis of sulfuric acid using titration. In such hazardous environments, the analyzer can be ex-proof or located in an ex-proof shelter.

This Process Application Note deals with online measurements of ammonia, nitrite, and nitrate in wastewater treatment plants. These nitrogen compounds are analyzed simultaneously using a drift-free colorimetric measurement in a multi-parameter process analyzer from Metrohm Process Analytics.

To optimize the wet-spinning process in the viscose/rayon production, it is crucial to measure sulfuric acid and zinc. H2SO4 and ZnSO4 are analyzed using a potentiometric titration and colorimetric measurement technique. Results are automatically validated against a known standard solution to guarantee preset control limits.

Permanganate absorption number (PAN) analysis per ISO 8660 ensures caprolactam purity, a precursor of Nylon 6. This application describes real-time, continuous PAN monitoring.

In an electroless plating bath, the consumed ingredients have to be regularly replenished to ensure an even layer of nickel-phosphorus alloy. This requires online monitoring of the active bath constituents. Parameters to be controlled are pH value (4.5–5.0) as well as nickel (NiSO4 < 10 g/L) and hypophosphite concentration (NaH2PO2: 1–12%). Other measurement options include sulfate, alkalinity, and organic additives (via CVS).

Boric acid requires precise monitoring in the primary circuit to control nuclear reactor reactivity. The 2060 TI Process Analyzer monitors boric acid online in near-real time.

This Process Application Note sheds light on the online monitoring of chloride in crude oil after desalting in order to check the desalting process efficiency and to overcome corrosion problems in downstream processes such as distillation. Chloride is analyzed with conductivity detection, as described in standard ASTM D3230.

This Process Application Note deals with the online monitoring of calcium and sulfate in flue gas scrubbing solutions using titration. Other contaminants that can be measured are sulfite, chloride, and chlorine. Low concentrations of heavy metals such as cadmium, zinc, copper, and lead can be measured in the ppb/ppm range with the ADI 2045VA Process Analyzer using voltammetry.

Excessive silica concentrations in the boiler feed water can lead to deposits on turbine blades and must therefore be avoided. Silica analysis is carried out via differential photometry using a leading-edge technology thermostatic cuvette module for non-sample contact at the detector. Typical concentration ranges for silica are 0–50 ppb and 0–1 ppm or higher.

Anodizing metal surfaces improves resistance against corrosion and wear. Etching baths can be monitored precisely online with the 2060 TI Process Analyzer or 2026 HD Titrolyzer.

Pickling baths are used in the galvanic industry to clean steel surfaces and prevent corrosion through passivation. Maintaining specific Fe2+/Fe3+ and free acid/total acid ratios is vital to ensure the baths' optimal performance, which directly impacts the final product quality and reduces production costs by minimizing reagent consumption. This application presents a method to regularly monitor the acid and iron composition in pickling baths online by using a process analyzer from Metrohm Process Analytics.

In the Solvay process, ammonium hydrogen carbonate and table salt are converted to sodium hydrogen carbonate and ammonium chloride. Heating the former yields sodium carbonate (soda), an important raw material for the soap and glass industries. Ammonia is an incipient and is regenerated almost completely through conversion of the ammonium chloride with lime milk (Ca(OH)2).A Metrohm process analyzer monitors the ammonia content in the saturated table salt solution after absorption tower, thus guaranteeing a good product yield in the carbonization tower. Additional parameters which can be determined with the analyzer in the Solvay process include: alkalinity, carbonate, chloride, calcium oxide and carbon dioxide.

Raw oil contains several percent by weight of sulfur compounds. They not only have an unpleasant smell, they are also environmentally harmful and corrosive which is why they must be largely removed during refining. The 2045TI Ex proof Analyzer with a flexible sample pretreatment system is to be found in a very wide variety of refinery applications. On the one hand, it monitors mercaptan and H2S content in accordance with ASTM D3227 and UOP163; on the other hand it can be used for the determination of ammonia, halogen and phenol content as well as for the bromide index, saponification and acid number. The analyzer fulfills EU Directive 94/9/EC (ATEX95) and is certified for Zones 1 and 2.

To prevent styrene from polymerization at ambient temperature, tertiary-butylcatechol (TBC) must be added as a stabilizer during storage and transport. TBC concentration levels in styrene need to be maintained between 10 - 15 mg/L. With optimum storage conditions, the process analyzers from Metrohm Applikon for photometric analyses ensure that the TBC concentration in styrene does not fall below this value. The method is based on ASTM D4590.

The chemicals used in the manufacture of semiconductors must exhibit an exceptional purity, because even traces of contaminants have a negative effect on electrical properties. For the manufacture of printed circuit boards, the light-sensitive photoresist applied to the substrate (wafer) is exposed to light at defined areas with the aid of a photo template and then developed in a chemical reaction. The developer contains 2.38 to 2.62% tetramethylammonium hydroxide (TMAH) and ensures that the exposed areas can be readily separated from the substrate. The monitoring of the TMAH concentration in the developer solution takes place with a process analyzer from Metrohm Applikon that is configured specially for titration. In addition to this, the analyzer helps with the mixing of the TMAH solutions.

Strict rules governing hygiene apply in the food and beverage industry. All surfaces of materials that come into contact with foods or beverages must be disinfected in order to ensure their bacteriological purity. Peracetic acid (PES) is often used for rapid disinfection of PET bottles. Correct dosing of the acid must be observed while doing so: Too much PES impairs taste and causes unnecessary costs through increased consumption. Insufficient concentrations on the other hand are unable to guarantee satisfactory cleaning. The PES concentration can be determined exactly using a process analyzer specially configured for photometric analyses. The analyzer sends an alarm signal to the control system if the concentration should deviate from the specifications.

Chromium is extracted from chromite ore and is an important part in the production of stainless steel. Chromium is mainly divalent, trivalent and hexavalent in its compounds. In contrast to chromium(III), which is an important trace element and one that is only sparingly soluble in water, hexavalent chromium is extremely toxic and very water-soluble. Cr(VI) is furthermore an important raw material for industry. It must be determined rapidly and precisely in the lower µg/L range in wastewater. Metrohm Applikon offers an array of process analyzers for the analysis of wastewater streams which determine chromium precisely and reproducibly using photometry.

Salmon farms are becoming ever more popular. Strong population growth increases the demand for salmon which has an effect on their cultivation. Ever more fish live in limited space in open net cages. Parasites such as salmon lice can multiply quickly due to the high density of fish. One possibility of fighting the lice is to use baths with weak concentrations of H2O2. The salmon are treated in these concentrations for up to 20 minutes until the lice fall away and die. While it is true that hydrogen peroxide decomposes relatively quickly, it is nonetheless deadly for salmon in higher concentrations. The concentration must therefore always lie within the specifications during treatment. Our process analyzer requires less than two minutes per titration. This means that it permits more concentration determinations per treatment and always guarantees the correct dosage.

Corrosion in the water-steam circuit of power plants leads to shorter lifetimes of most metal components and potentially dangerous situations. Flow Accelerated Corrosion (FAC) is a specific case, leading to thinned pipes and elevated Fe concentrations in the circuit. Additionally, metal transport issues such as with Cu from copper heat exchangers can lead to deposition on the high pressure turbine blades, decreasing their efficiency. Current methods can monitor but not prevent these issues, and analysis times are extremely long (up to three weeks). In combination with the power plant’s Distributed Control System (DCS), online monitoring of Fe and Cu with the 2060 Process Analyzer from Metrohm Process Analytics ensures that corrosion can be controlled before it affects the power plant efficiency, ultimately decreasing downtime and lowering maintenance costs. Results are offered within 20 minutes, allowing fast adjustments to the water-steam circuit to protect company assets.

The Bayer Process is the method used to refine alumina from bauxite ore, as smelting aluminum directly from alumina is much more cost- and energy-effective. In this process, "aluminate liquors" are created by digesting the crushed bauxite with CaO and NaOH at high temperatures. Additionally, the CaO causticizes carbonate which forms in the alkaline solution from organic degradation and CO2 absorption from the atmosphere. Contaminations are removed at various steps in the process, and the liquor is filtered from the alumina crystals before it is recycled back to the digestion step. Before the spent liquor can be reused, a determination of the concentrations of the total hydroxyl (“caustic”), carbonate, and alumina values is required. These parameters can be determined quickly via thermometric titration with the 2035 Process Analyzer.

The size of the indigo molecule makes it difficult to dye synthetic fibers, but the large pores of cellulose (such as in cotton) accept it readily. Indigo is insoluble in water, so it must first be reduced to the water-soluble leuco-indigo form by sodium hydrosulfite in a strong alkaline bath. Good circulation within the bath is imperative for consistent dye coverage, but care must be taken not to introduce any oxygen. Fabrics must be oxidized between dips in the dye bath in order to set the indigo within the pores of the fibers, but multiple dips are necessary for darker, uniform coverage. Many parameters need to be monitored and controlled to ensure high quality of the end product: the pH value for proper NaOH (alkali) dosage, the concentrations of both hydrosulfite and indigo, as well as the temperature of the bath and even the redox potential.

Beer is a popular beverage consumed by millions of people for enjoyment, despite its humble beginnings as a water purification technique in pre-modern times. Brewing beer requires large amounts of water which must adhere to strict alkalinity, hardness, and pH parameters to ensure uniformity in flavor and appearance between each batch. Alkalinity is introduced by carbonates and hydroxides in water which raise and buffer the pH. Hardness, balanced to a large degree by the alkalinity, comes from Ca and Mg ions, mainly present as hydrogen carbonates. Depending on the concentration ranges, the 2035 Process Analyzer or the 2060 Process Analyzer are ideally suited for the fully automatic execution of these important analyses, as well as additional parameters like pH or conductivity. These process analyzers can signal the plant’s distribution system to correct the water chemistry, ensuring consistent product quality. In addition to alkalinity and water hardness, numerous other parameters can also be determined (pH, conductivity, etc.).

Metrohm has partnered with industry leaders to develop an alternative standard for the measurement of acid number (AN) in crude oil and petroleum products to overcome shortcomings in the current method (ASTM D664). This new standard method (ASTM D8045) describes the use of thermometric catalytic titration for this analysis. Results agree closely with those from ASTM D664, but the thermometric catalytic titration method is far superior in terms of reproducibility and speed of analysis, with determinations being complete in one minute.Solvent usage is much less compared to older methods, saving on waste disposal cost. Comparison studies show very close data correlation between ASTM D8045 and traditional potentiometric AN titration methods making implementation into a refinery with historic data practical.

One way to maximize heat transfer efficiency and reduce costs in a power plant is by controlling the water chemistry in the cooling circuit. This cooling water is kept alkaline to maintain the protective oxide layer on the metal piping throughout the water circuit. However alkalinity above the recommended range increases the probability of scale formation (deposition), so it is buffered with carbonate (CO32-) and bicarbonate ions (HCO3-). Titration of the cooling water to pH 4.5 gives the so-called "M-Alkalinity" (methyl orange alkalinity), a measure of total alkalinity. Below this pH, there is no more alkalinity present, only free acid (H+), carbonic acid (H2CO3), and CO2.

Phosphorus removal is essential in waste water treatment plants to ensure the environmental balance is not upset by discharged effluent. In the treatment facility it is important to know the bioavailable o-phosphate phosphorus (o-PO4-P) concentration in the influent stream either to feed bacteria or to calculate the amount of reagents needed for chemical treatment. For environmental compliance monitoring purposes, treated effluent is monitored for TP – the sum of all insoluble and dissolved phosphates present. With the Metrohm Process Analytics 2035 TP Analyzer (complete with integrated compact digestion cuvette photometer module), you can keep track of both o-PO4-P and TP according to DIN EN ISO 6878:2004-09 around the clock.

Thermal power plants require enormous amounts of water, using high purity steam at high pressure to rotate turbines. A separate cooling water circuit is implemented, which helps to form a vacuum when the steam condenses after the turbines. Maintaining this vacuum with optimal condensation parameters is critical for the power plant efficiency. The copper condensers are susceptible to corrosion by ammonia, leading to an upper limit of 2 mg/L NH3 set by EPRI in cooling water. Small cracks in the condenser combined with the large pressure differential between the steam circuit and the cooling water circuit will contaminate the high purity water in the boiler, causing major problems and necessitating a shutdown for plant maintenance. Monitoring NH3 online in cooling water with a process analyzer can signal early problems in a plant before significant intermediation is necessary.

Polyurethanes are a class of synthetic polymers formed by reacting liquid di/polyisocyanates and polyols with a catalyst and various additives in a reactor. Polymer properties are modified with stepwise additions of these chemicals at different points in time depending on whether the process has reached an equilibrium. NCO functional groups from unreacted isocyanates must be quenched at the end for a finished product, and this parameter must be known to determine the proper chemical mixing ratio. A fast, non-destructive real-time measurement of %NCO can be obtained by using NIR spectroscopy with a probe seated directly in the reactor.

Measures to monitor or prevent corrosion are crucial in nuclear power plants, where significant risks to health and safety can occur if corrosion is left unchecked. Anions corrode metals under high temperature and pressure, therefore their concentrations must be monitored at all times. The analytical challenge in the primary circuit is detection of anions in the μg/L range alongside gram quantities of boric acid and lithium hydroxide. Precise, reliable trace analysis requires the method to be automated as much as possible. The 2060 IC Process Analyzer from Metrohm Process Analytics can measure several anions from a single injection, with combined Inline Preconcentration and Inline Matrix Elimination to measure low anion concentrations precisely and reliably time after time.

In power plants, corrosion is the primary factor leading to costly and critical downtimes. In a nuclear power plant, a separate water circuit known as the Pressurized Water Reactor (PWR) ensures radioactive material stays contained while still transferring heat and energy to the other circuits. Boric acid and lithium hydroxide are added specially to the PWR circuit in amounts which can complicate other analytical measurements. Lithium prevents corrosion and must be monitored, along with other cations such as zinc, nickel, and ammonium. In order to measure these cations online at sub-µg/L range in a single analysis, the 2060 IC Process Analyzer is offered with combined Inline Preconcentration and Inline Matrix Elimination. Several cations can be analyzed in a single injection, with automated sample preparation making precise and reliable measurements easier.

Neutralizing amines are added to adjust pH levels within the water-steam circuit of power plants to avoid corrosion-inducing conditions. This preventive maintenance can reduce costly and critical downtimes due to corrosion, however frequent monitoring of the amine chemistry is necessary to ensure conditions stay optimal. The 2060 IC Process Analyzer featuring the Metrohm intelligent Partial Loop Technique (MiPT) option is ideal for this application, with the ability to measure trace amounts of the analytes precisely and reliably through an automated method. The benefit of using IC is that multiple analytes can be monitored simultaneously, and here the ability to measure the presence of sodium next to the high ammonium or amine concentrations could indicate that cooling water is seeping into the circuit, indicating a problem upstream.

Copper is used widely in industrial cooling water systems for its heat transfer properties, although it is susceptible to corrosion. Corrosion can cause a loss of efficiency and eventually a failure of equipment, leading to costly maintenance, replacement, and downtime. Corrosion inhibitors (triazoles) can be added to the water chemistry, which form sparingly soluble protective layers on the surface of the metal. Triazole concentrations must be maintained to protect the copper, which necessitates regular concentration determinations in cooling water. The 2060 IC Process Analyzer with UV/VIS detection is well-suited for this application, able to precisely and reliably measure multiple ionic and UV-active compounds simultaneously in cooling water.

The basic chemicals industry is responsible for producing thousands of raw materials at very large scales. The industries downstream rely upon a certain level of chemical purity to manufacture their own goods, as certain impurities can cause major issues in various processes. During the production of the basic chemicals NaOH and KOH, electrolysis of saturated brine solutions with membrane-cells yield the product which is further concentrated by evaporation. Impurities from the salts used in the brine will also be concentrated. Typically, this impurity analysis is performed offline with various hazardous chemicals with varying shelf-lives. The Process Ion Chromatograph is able to perform the measurement described in ASTM E1787-16 online, ensuring quality product without the need for time-consuming, hazardous laboratory experiments.

A safer way to monitor moisture content in crude distillation unit overhead fractions is with inline near-infrared spectroscopy using the 2060 The NIR-Ex Analyzer.

This Process Application Note provides a detailed account of the inline assessment of moisture during a pilot scale granulation process using a 2060 The NIR Analyzer.

Drinking water which has been disinfected via the ozonation process can contain undesirable levels of bromate, a carcinogen, via oxidation of bromide in the raw water. Already several agencies including the World Health Organization have recommended concentration limits for bromate set in place to limit its risks to our health. Ion chromatography is mentioned in several analytical standards for the determination of disinfection byproducts (DBP) including bromate, such as EPA 300.1, 317.0, 321.8, 326.0, ASTM D6581, ISO 11206, and ISO 15061. Monitoring trace levels of bromate online means higher throughput and less time spent performing manual laboratory tests, and ensures quality drinking water is produced.

In the pharmaceutical industry, the fluid bed granulator/dryer is an integral point in the manufacture of powdered materials. Residual moisture must be kept within certain specifications to avoid fracturing of particles or caking (stickiness) of the bulk material. Current methods are slow and cumbersome, which can lead to damaged or degraded product. The ability to monitor the residual moisture content inline after drying is possible with near-infrared spectroscopy (NIRS). The 2060 The NIR Analyzer offers fast, reagent-free, nondestructive analysis of residual moisture of powders with a fluid bed probe specifically designed for these applications.

This Process Application Note presents a method to closely monitor low levels of moisture in propylene oxide safely and reliably by using a single explosion-proof inline process analyzer.