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Recognition of endpoints (EP)

Recognition of endpoints (EP)

Like many of you, I gained my first practical titration experience during my chemistry studies in school. At this time, I learned how to perform a manual visual endpoint titration – and I can still remember exactly how I felt about it.

Using a manual buret filled with titrant, I added each drop individually to an Erlenmeyer flask that contained the sample solution (including the analyte to be measured) and the indicator which was added prior to the titration. With each drop and even slight color change of my sample solution, minutes passed with increasing uncertainty. I asked myself, «Have I already reached the true endpoint, should I add another drop, or have I even over-titrated?» You have probably been in the same situation yourself!

Sound familiar to you? Don’t forget to check out our other blog post about the main error sources in manual titration!

Several years have passed since then, and I am glad that I no longer have to face the challenges of performing a manual titration because Metrohm offers the possibility of automated titrations.

If you want to know how to determine the endpoint in an automated titration, I will give you all the answers you need. In the following article I will cover these topics (click to go directly to each):

    Different detection principles – an overview

    At this point you may ask yourself—if not visually, how the endpoint (EP) can be detected in an automated titration? Well, aside from the visual endpoint recognition (e.g., by a color change, the appearance of turbidity, or appearance of a precipitate), a titration EP can also be detected by the automated monitoring of a change in a chemical or physical property which occurs when the reaction is complete.

    As shown in the table below, there are many different detection principles:

    Now, let’s discuss the potentiometric and photometric EP determination in comparison to a visually recognized EP detection as they are the most commonly used determination principles for automated titrations. If you’d like to learn more about the principles of thermometric titration, read our blog post about the basics!

    Potentiometric principle

    As shown in the table above, in the potentiometric principle the concentration dependent potential (mV) of a solution is measured against a reference potential. Therefore, a silver-silver chloride (Ag/AgCl) reference electrode is used in combination with a measuring electrode (pH sensitive glass membrane or metal ring). In general, a combined sensor (electrode) including both measuring and reference electrode is used.

    Figure 1 illustrates with a simple example how a manual titration with a color change looks when being converted to an automatic system.

    Figure 1. Illustration of the same titration performed manually (left) and automatically (right).

    Step 1: Beginning of the titration before titrant is added.

    Step 2: Addition of titrant – as the titration approaches the endpoint you begin to see signs of the color change. At this point in an automatic titration the sensor will detect a change in mV signal and the titrator begins dosing the titrant in smaller volumes and at a slower rate.

    Step 3: Finally, the EP is reached with a faint pink color which corresponds with the inflection point in the titration curve.

    Step 4: Titrating beyond the endpoint leads to over titration, and here the mV signal is fairly constant.

    This is how you achieve the characteristic S-shaped titration curve you see when performing an automated titration.

    Not only acid-base titrations can be converted. Figure 2 shows how a simple chloride titration can be converted. The titrant, titrant concentration, sample size, and sample preparation remain the same.

    Figure 2. Illustration of a chloride titration – conversion from manual to automatic analysis.

    Only the indicator is replaced by the Ag Titrode, a silver ring electrode, and we get a titration curve (Figure 2, right side) with a clearly defined endpoint.

    For more examples of possible potentiometric titrations, download our free monograph «Practical Titration» or check out our Application Finder where you can find several examples for all endpoint recognition principles.

    Photometric Principle

    Titrations using color indicators are still widely used e.g. in pharmacopeias. When performed manually, the results depend, quite literally, on the eye of the beholder. Photometric titration using the Optrode makes it possible to replace this subjective determination of the equivalence point with an objective process that is completely independent of the human eye.

    The advantage here is that the chemistry does not change – that is, the standard operating procedure (SOP) generally does not have to be adapted. 

    The basis of photometric indication is the change in intensity at a particular wavelength of a light beam passing through a solution. The transmission is the primary measured variable in photometry, and is given by the light transmission (mV or % transmission) of a colored or turbid solution that is measured with a photometric sensor such as the Optrode from Metrohm.

    There are eight possible wavelengths to choose from that span nearly all color indicators used for titrations (see table below). The shaft is solvent resistant and there is no maintenance required. It connects directly to the titrator and improves accuracy and repeatability of color indicated titrations.

    I’ve also picked an example to show you how to convert an EDTA titration of manganese sulfate from manual titration to automated titration. Like in the example above, the procedure remains the same.

    Are you ready to take the leap and switch to using an automated titration system? Read our other blog post to learn more about how to transfer manual titration to autotitration.

    One advantage of automated titration is that a lower volume of chemicals is needed, resulting in less waste. With the same indicator Eriochrome Black TS, the Optrode is used at a wavelength of 610 nm. The titration curve (Figure 3, right side) shows a large potential change of the mV signal indicating a clearly defined titration endpoint.

    Figure 3. Illustration of the photometric EDTA titration of manganese sulfate according to USP.

    If you are not sure what the optimal wavelength for your titration is, then have a look at our blog post about photometric complexometric titration to learn more!

    Comparison: Optrode vs. potentiometric electrodes

    When you decide to make the switch to automated titration, there are some points to consider when comparing the Optrode with other Metrohm potentiometric electrodes. The following table lists the main criteria.

    1Optrode has a working life of tens of thousands of hours.

    You see, an autotitration is quite simple to perform and has the great advantage that a clearly defined endpoint is given.

    Believe me, whenever I`m working with such a device including a suitable electrode for an automatic titration, I have a big smile on my face thinking back to my university days: Bye bye subjectivity, time-consuming procedure, economic inefficiency and non-traceability!

    Maybe you are now also convinced to make the change in your laboratory.

    Save more money

    with automated titration

    Read our blog post to find out more.

    Post written by Doris Hoffmann, Product Manager Titration at Metrohm International Headquarters, Herisau, Switzerland.

    Easy moisture determination in fertilizers by near-infrared spectroscopy

    Easy moisture determination in fertilizers by near-infrared spectroscopy

    Blooms or bombs?

    As the global population steadily increases, it is important that sufficient crops are produced each year to provide enough food, clothing, and other products. Crops such as corn, wheat, soy, and cotton receive nutrients from the soil they are grown in. Fertilizers play a crucial role in providing these crops with the nutrients they need to grow properly.

    An important ingredient in the production of high quality, effective fertilizers is ammonium nitrate (NH4NO3), a good source of nitrogen and ammonium for plants.

    Produced as small beads similar in appearance to kitchen salt, ammonium nitrate is cheap to buy and usually safe to handle – but storing it can be a problem. Over time, the compound absorbs moisture, which leads to clumping of the individual beads into a larger block. When such a large quantity of compacted ammonium nitrate is exposed to intense heat it can trigger an explosion.

    Over the last century, ammonium nitrate has been involved in at least 30 disasters and terrorist attacks. One of the most recent occurrences was on the evening of August 4th, 2020 in Beirut, where an ammonium nitrate explosion killed at least 220 people and injured more than 5000. This blast is one of the largest industrial disasters ever linked to NH4NO3.

    Moisture analysis methods for fertilizers

    During the production process of ammonium nitrate it is important to control the moisture content. A low moisture content is preferable, but unnecessary excess drying leads to additional manufacturing costs.  Regulations for different fertilizers vary across the globe, but local legal limits ensure that the maximum amount of water present must not be exceeded.  Therefore,  rapid, reliable, and accurate methods for the determination of moisture is necessary. Out of those available, Karl Fischer titration is one of the most common; oven drying, for example, cannot be used with fertilizers containing ammonium nitrate.

    Compared to these methods, near-infrared spectroscopy (NIRS) offers unique advantages. It is a secondary technique that generates reliable results within seconds without needing any sample preparation. NIRS is a non-destructive measurement technique and at the same time does not create any chemical waste.

    Read our previous blog posts below to learn more about NIRS as a secondary technique.

    NIRS analysis of solids

    The most suitable NIR analyzer to measuring different parameters in fertilizer or ammonium nitrate pellets is the Metrohm DS2500 Solid Analyzer with Large Sample Cup.

    Solid samples (e.g., granules and pellets) that are filled in the rotating DS2500 Large Sample Cup must be placed on the analyzer window. While scanning the sample, the Large Sample Cup will rotate in order to compensate for inhomogeneity.

    As the DS2500 Solid Analyzer is a pre-dispersive system, the sample is illuminated with monochromatic light in order to keep the energy level as low as possible. Therefore, the instrument lid must be closed prior to starting the analysis so external light does not affect the results. The NIR radiation comes from below and is partially reflected by the sample to the detector, which is also located below the sample vessel plane. After 45 seconds, the measurement is completed, and a result is displayed. As this reflected light contains all the relevant sample information, this measurement technique is called diffuse reflection.

    Advantages of using NIRS

    The procedure for obtaining the NIR spectrum already highlights its simplicity regarding sample measurement and its speed. Several advantages of NIRS are listed below:

     

    • Fast technique with results in less than 1 minute.
    • No sample preparation required – solids and liquids can be used in pure form.
    • Low cost per sample – no chemicals or solvents needed.
    • Environmentally friendly technique – no waste generated.
    • Non-destructive – precious samples can be reused after analysis.
    • Multiple component analysis – prediction of different constituents in parallel.
    • Easy to operate – inexperienced users are immediately successful.

    Overall, near-infrared spectroscopy is a robust alternative technique for the determination of both chemical and physical parameters in solids and liquids. It is a fast method which can also be successfully implemented for routine analysis by staff without any higher laboratory education.

    Related Applications

    Specialty chemicals have to fulfill multiple quality requirements. One of these quality parameters, which can be found in almost all certificates of analysis and specifications, is the moisture content. The standard method for the determination of moisture content is Karl Fischer titration.

    This method requires reproducible sample preparation, chemicals, and waste disposal. Alternatively, near-infrared spectroscopy can be used for the determination of moisture content. With this technique, samples can be analyzed without any preparation and without using any chemicals.

    More information about the application details can be found below!

    Moisture content is one of the most commonly measured properties of fertilizers. Globally, regulations for different fertilizers vary, but local legal limits ensure that the maximum amount of water must not be exceeded. A number of analytical techniques are available for this purpose. Next to gravimetric methods, Karl Fischer titration is often used for accurate moisture determination.

    Compared to these methods, near-infrared spectroscopy offers unique advantages: it generates reliable results within seconds, and at the same time does not create chemical waste. This Application Note explains how NIRS can offer fast, reagent-free analysis of moisture content in various fertilizer products.

    Read on for more technical details…

    To learn more about how Karl Fischer titration and NIRS complement each other for the analysis of moisture in different products, read our blog post!

    For more information

    About spectroscopy solutions provided by Metrohm, visit our website!

    We offer NIRS for lab, NIRS for process, as well as Raman solutions

    Post written by Wim Guns, International Sales Support Spectroscopy at Metrohm International Headquarters, Herisau, Switzerland.

    Real World Raman: Simplifying Incoming Raw Material Inspection

    Real World Raman: Simplifying Incoming Raw Material Inspection

    Raw material identification and verification (RMID) is a complicated process for a very important reason: it confirms the quality of the raw materials used in the manufacture of products that you put on and in your body. The complexity of RMID spans the spectrum from analytical techniques and instruments to the testing process, then to the governmental norms and standards that regulate all aspects of RMID including system suitability, extent of sampling, method validation, electronic records, and many others.

    With Mira P and Mira Cal P, Metrohm Raman simplifies RMID.

    Warehouse verification of incoming materials with mobile Raman in regulated industries involves performing RMID directly at the loading dock. Therefore, chemical analyses that historically would be performed in a laboratory by trained chemists can now be performed very quickly and with great success by nontechnical professionals.

    Beginning with System Suitability…

    Producers of handheld Raman instruments for RMID must provide suitable calibration and validation routines. Calibration of Mira P with the Calibrate/Verify Accessory (CVA) accomplishes instrument calibration as well as system and performance verification, then summarizes these tests in the System Suitability Test (SST) report for Mira P. CVA ensures that Mira P performs as intended and that users can trust in the generated data quality. Upon completion of the SST, users are assured that all measurements are in accordance with agreed standards.

    For more information about instrument calibration, system verification, and performance validation for Metrohm Instant Raman Analyzers (Mira), download our free White Paper!

    Moving on to Sampling Flexibility…

    RMID methods must accommodate a number of factors to create the most accurate and robust solution for the task. Specific consideration must be given to:

    1. The sampling strategy: how to collect the best quality data, given specific conditions
    2. Sample presentation: including morphology, packaging, and chemical nature

    Handheld Raman is recognized as a particularly well-suited technique for RMID, as it offers portable, onsite, no-contact analysis of solid and liquid samples.

    RMID for Regulated Industries Part I: General Considerations outlines basic applications of handheld Raman, including sampling considerations and types of evaluation. Metrohm Raman simplifies sampling with Smart Tips for every sample type.

    Followed by Method Development…

    From Training and Validation Set building and specific recommendations for collecting best quality spectra to dedicated software routines that automatically determine optimal model parameters, Mira P streamlines development of methods for RMID with handheld Raman.

    Successful development of a method relies on the inclusion of spectra in libraries and training sets used for RMID. Careful planning in the design phase of the model leads to an easy data collection phase. This data can then be used to determine the best model parameters for robust method development. With Mira Cal P and ModelExpert, even non-technical users can implement accurate, effective RMID methods.

    Download our free Application Note AN-RS-031 for more information about Simplified RMID Model Building with Mira Cal P and Model Expert!

    And Method Implementation…

    Implementation of handheld Raman in RMID, where the majority of materials testing is performed in the receiving area, is a logical step for such a powerful technique. It has become widespread due to some very real advantages.

    Massive time savings: acquisition times of less than a minute, coupled with instant, obvious results, permits very high-throughput

    Faster turnaround: delivers materials to production sooner

    Reduced resources: less demand for laboratory and warehouse personnel and lab consumables, costs, and workloads

    Guided Workflows: predefined workflows on Mira P make sampling simple and efficient

    With Full Compliance and Utter Confidence.

    Just as Mira P has built-in routines to ensure instrument integrity, Mira Cal P is designed to protect customer data integrity and simplify compliance with worldwide norms and standards. All RMID customers require data to be complete, consistent, and accurate, and MiraCal P goes beyond this with full transparency and traceability.

    MiraCal P analytical software from Metrohm Raman gives you peace of mind, as it ensures all data processing adheres to several standards. More information about data integrity can be found in our free flyer.

    RMID is a complex process. Learn more about how handheld Raman can provide the simplest, most efficient and accurate RMID experience possible.

    Learn more about

    Handheld Raman spectrometers and SERS analyzers for the lab and the process

    Post written by Dr. Melissa J. Gelwicks, Applications Chemist, Metrohm Raman, Laramie, Wyoming, USA.

    Analysis of prebiotics with IC-PAD: Improving AOAC 2001.02

    Analysis of prebiotics with IC-PAD: Improving AOAC 2001.02

    Our diet is critical for our health. In the past several years, interest has increased in food additives and dietary supplements such as prebiotics like β-galactooligosaccharides (GOSs). The determination of total GOS contents in food and supplements is essential to fulfill strict food labeling and safety requirements. The most widely used method for total GOS determination is based on enzymatic hydrolysis to break down the complex molecules into simple carbohydrates prior to their chromatographic analysis. This article outlines the advantage of using an improvement to AOAC Method 2001.02 using ion chromatography with amperometric detection (IC-PAD) and full sample automation after enzymatic hydrolysis.

    What are GOSs?

    GOSs are chains of galactose units with an optional glucose end. They are often naturally present in small amounts in various foods and beverages.

    Initially discovered as major constituents of human breast milk (present up to 12 g/L), GOSs are added as a prebiotic supplement to infant formulas. They show bifidogenic effects, meaning they support growth and well-being of non-pathogenic gut bacteria.

    GOS supplements are available either raw, or as concentrated powders or syrups, and are subsequently used by food manufacturers to enrich consumer products or sold as supplements.

    GOS labeling requirements

    The ongoing growth of global prebiotic and GOS markets is a result of increasing consumer awareness regarding healthy eating. Similarly, increased demand regarding food quality has led to stricter, more comprehensive rules for food labeling and safety (e.g., EU 1169/2011 and  EU 2015/2283). The determination of total GOS contents in food, supplements, or raw products is thus essential to fulfill such requirements.

    Studies about GOS health effects recommend maximum doses under 30 g per day, though this is much stricter for infant formulas. Otherwise, there are no other limits regarding GOS content in food or as nutritional supplements.

    AOAC 2001.02

    The most widely used method to measure total GOSs in food products is the standard method AOAC 2001.02. This method is based on the extraction of GOS from a sample followed by enzymatic hydrolysis of the oligosaccharides into monosaccharides and their subsequent analyses with high performance anion exchange chromatography with pulsed amperometric detection.

    Figure 1. Schematic for determination of total GOS contents using ion chromatography with pulsed amperometric detection (IC-PAD) according to AOAC 2001.02, and an optimized method from Metrohm (in green). Chromatography for anions in AOAC is referred as HPAEC (high performance anion exchange chromatography) but is simplified here to the generic term of IC.

    In AOAC, chromatography for anions is referred to as HPAEC (high performance anion exchange chromatography) but here we will simplify this to the generic term of IC.

    The key to AOAC 2001.02 is the comparison of a control solution with one which has been treated and hydrolyzed with an enzyme (β-galactosidase). The enzyme catalyzes the splitting of glycosidic bonds and hydrolyzes GOSs and lactose into glucose and galactose. The concentration differences of free galactose and lactose determined in these two solutions is used to calculate the total GOSs (Figure 1).

    Improvements to the AOAC Method

    The sample preparation for AOAC 2001.02 is rather complex: one shortcoming is the incubation of the reference solution with the deactivated enzyme (which is rather expensive) to determine the initial carbohydrate concentrations (Figure 1) rather than using the pure extract. Another critical point is the sample dilution procedure, which is supposed to be done in acetonitrile, while standards are based on ultrapure water.

    Here, the focus was to simplify the entire procedure to increase the ease of use and the overall efficiency of the method.

    The improved method for total GOS content analysis uses the extract for measuring of the initial glucose, galactose, and lactose concentrations (Figure 1 Assay 1). However, the deactivated enzyme was not used, and instead comparisons were made to see if its presence had any effect on the results. This step was eliminated after proving results equivalent to AOAC 2001.02 Assay 1 (with the deactivated enzyme), but chemical expenses and additional manual work are reduced. The total GOS content is therefore calculated from the analyte concentrations in Assay 1 (without any enzyme) and Assay 2 (extract with the active enzyme) (Figure 2).

    Figure 2. Overlaid chromatograms of Bimuno (prebiotic supplement), untreated (black) and treated with enzyme (orange).

    Want to know more details about the application? Download our free Application Note AN-P-087 about total GOS analysis in foods with ion chromatography!

    Aside from the enzyme usage, the official AOAC method for analysis of total GOSs suggests that standards be prepared in ultrapure water (UPW) while samples are to be diluted with 20% acetonitrile. A control experiment was performed to compare results between:

    • Dilutions in UPW evaluated with UPW calibration (“UPW option”)
    • Dilutions in acetonitrile evaluated with UPW calibration (AOAC 2001.02)
    • Dilutions in acetonitrile evaluated with acetonitrile calibration (“ACN option”)

    Reproducibility of total GOS contents was compared among the three options, with the UPW and AOAC preparation options exhibiting similar results. The ACN option resulted in lower total GOS contents than the others. Additionally, the acetonitrile did not seem to lend a stabilizing effect to the samples. This supports the improvement of the AOAC method by performing sample dilutions with UPW instead of acetonitrile, saving unnecessary reagents and limiting the chemical imprint of the analysis.

    Results

    Overall, the satisfying variability, target and spike recoveries (Application Note AN-P-087), together with the interference tests proved the modified method as valuable and robust. With limits of detection (LODs) of 0.1 mg/L (galactose) and 0.2 mg/L (glucose, lactose) in solution, even low total GOS contents can be determined with high precision.

    Summary

    As a multicomponent method, ion chromatography with amperometric detection is a very selective, sensitive, and robust analysis method for carbohydrates without any additional derivatization steps. In combination with enzymatic treatment, even more complex carbohydrates can be quantified.

    This research presents an update to the standard AOAC method for total GOS determination in foodstuffs. With the same principle (enzymatic hydrolysis of complex GOS molecules followed by chromatographic analysis of simple carbohydrates), analytical method efficiency was improved in favor of laboratory time and running costs. Additional automation steps (e.g., Metrohm Inline Dilution and automatic calibrations) can further improve the method efficiency.

    Want more information about the simplified method for total GOSs via IC-PAD? More details about the improvement of AOAC method 2001.02 by reducing manual laboratory work and eliminating expensive reagents can be found in our article published in The Column from LC/GC (2021): Improving on AOAC 2001.02: GOS Determination in Foods Using HPAEC–PAD.

    Read our article in LC/GC The Column (2021)

    Improving on AOAC 2001.02: GOS Determination in Foods Using HPAEC–PAD

    Post written by Dr. Alyson Lanciki, Scientific Editor at Metrohm International Headquarters, Herisau, Switzerland.

    Unmatched flexibility in online ion analysis: The 2060 IC Process Analyzer

    Unmatched flexibility in online ion analysis: The 2060 IC Process Analyzer

    When discussing chemical analysis, the first thing that comes to mind is a chemist working in the laboratory analyzing a sample.

    However, in the industrial process world chemical analysis is a much more complicated affair. In the metalworking industry for example, corrosion is a complex problem. The conventional approach (offline analysis systems) is costly, and a more proactive approach is needed for prevention, identification, and manufacturing of high quality metalworking products. Therefore, a more comprehensive sample monitoring and analysis approach is necessary in order to comply with such requirements.

    While offline analysis systems depend upon an analyst to collect and process samples, an online analysis system allows for continuous monitoring of multiple parameters in real time without being dependent on an analyst.

    Need to refresh your knowledge about the differences between online, inline, and atline analysis? Read our blog post: «We are pioneers: Metrohm Process Analytics».

    The implementation of Process Analytical Technologies (PAT) provides a detailed representation in real time of the actual conditions within a process. As a complete solution provider, Metrohm Process Analytics offers the best solutions for online chemical analysis. We seek to optimize process analysis by developing flexible, modular process analyzers that allow multiple analyses of different analytes from a representative sample taken directly at the process site.

    Want to learn more about PAT? Check out our article series here: «To automate or not to automate? Advantages of PAT – Part 1».

    2060 IC Process Analyzer

    With more than 40 years of experience with online process analysis, Metrohm Process Analytics has always been committed to innovation. In 2001, the first modular IC system was developed at Metrohm and it was a success. In the past several years Metrohm Process Analytics focused on implementing more modular flexibility in their products, which resulted in the introduction of the next generation of Process Ion Chromatographs: the 2060 IC Process Analyzer (Figure 1) in 2019. It is built using two 930 Compact IC Flex systems and is in full synergy with the Metrohm process analyzer portfolio (such as the 2060 Process Analyzer).

    Figure 1. The 2060 IC Process Analyzer from Metrohm Process Analytics. Pictured here is the touchscreen human interface, the analytical wet part (featuring additional sample preparation modules – top inlay, and the integrated IC – bottom inlay), and a reagent cabinet.

    For more background behind the development of IC solutions for the process world, check out our previous blog posts featuring the past of the 2060 IC Process Analyzer:

    Using the 2060 platform, modularity is taken to the next step. Configurations of up to four wet part cabinets allow numerous combinations of multiple analysis modules for multiparameter measurements on multiple process streams, making this analyzer unequal to any other on the market.

    This modular architecture gives the additional possibility to place separate cabinets in different locations around a production site for a wide angle view of the process. For example, the 2060 IC Process Analyzer can be set up at different locations to prevent corrosion on the water steam cycles in fossil and nuclear power plants.

    The 2060 IC Process Analyzer is managed using flexible software enabling straightforward efficient control and programming options. With multiple types of detectors available from Metrohm, high precision analysis of a wide spectrum of analytes is possible in parallel.

    The inclusion of an optional (pressureless) ultrapure water system for autonomous operation and reliable trace analysis also benefits users by providing continuous eluent production possibilities for unattended operation (Figure 2).

    Finally, the well-known Metrohm Inline Sample Preparation (MISP) techniques are an added bonus for process engineers for repeatable, fully automated preparation of challenging sample matrices.

    Figure 2. Continuous eluent production integrated in the 2060 IC Process Analyzer.

    Top applications

    The collection of samples and process data, including corrosion prevention and control indicators, is critical for efficient plant management in many industries. In order to prevent unscheduled plant shutdowns, accidents, and damage to company assets, process engineers rely on their colleagues in the lab to pinpoint corrosion problems. One of the most effective ways to bridge laboratory analyses to the process environment is to employ real-time analysis monitoring.

    Figure 3. Product and process optimization differences between offline, atline, online, and inline analysis.

    Optimal online corrosion management

    Be it quantifying the harmful corrosive ions (e.g., chlorides, sulfates, or organic acids), measuring corrosion inhibitors (e.g., ammonia, amines, and film-forming amines), or detecting corrosion products, the 2060 IC Process Analyzer is the ideal solution for 24/7 unattended analysis.

    In a nuclear power plant, this analyzer can measure a number of analytes including inorganic anions, organic cations, and aliphatic amines to ensure a thorough understanding of corrosive indications without needing multiple instruments.

    Figure 4. Water sample from the primary circuit of a pressurized water reactor containing 2 g/L H3BO3 and 3.3 mg/L LiOH spiked with 2 μg/L anions (preconcentration volume: 2000 μL).
    Figure 5. Simulated sample from the primary circuit of a pressurized water reactor containing 2 g/L H3BO3 and 3.3 mg/L LiOH spiked with 2 μg/L nickel, zinc, calcium, and magnesium (preconcentration volume: 1000 μL).

    Providing quick, reliable results, this system gives valuable insight into the status of corrosion processes within a plant by continuous comparison of results with control values. By correlating the results with specific events, effective corrective action can quickly be undertaken to prevent or minimize plant downtime.

    For more information about the determination of anions and cations in the primary circuit of nuclear power plants with the 2060 IC Process Analyzer, download our free Application Notes below.

    Online drinking water analysis

    In drinking water plants and beverage bottling companies, determination of disinfection byproducts (DBPs) like bromate is crucial due to their carcinogenic properties. The carcinogen bromate (BrO3) has a recommended concentration limit of 10 μg/L of in drinking water set by the World Health Organization.

    Nowadays, ion chromatography has been proven to be the best routine analysis method for water analysis, due to its possibility of automated sample preparation, various separation mechanisms, and different types of detectors. Some of the analytical standards that support this include: EPA 300.1EPA 321.8, ASTM D6581, ISO 11206, and ISO 15061.

    The 2060 IC Process Analyzer can monitor trace levels of bromate in drinking water online, meaning higher throughput, less time spent performing manual laboratory tests, and better quality drinking water.

    Figure 6. Drinking water sample, spiked with 10 μg/L each of chlorite, bromate, chlorate, 40 μg/L each of nitrate, bromide, 100 μg/L phosphate, and 500 μg/L dichloroacetate.
    Figure 7. Analysis of a mineral water sample spiked with 0.5 μg/L bromate.

    To learn more about the online analysis of bromate in drinking water with the 2060 IC Process Analyzer, download our free Application Note.

    Monitoring aerosols and gases in air

    Approximately 92% of the world population lives in places where the World Health Organization air quality guideline levels are not met. Air pollution can exacerbate preexisting health conditions and shorten lifespans. It has even been suggested as a link to infertility causes. Hence, understanding the impact of air pollution and air constituents on the environment and our wellbeing is of great significance.

    Air pollution is caused not only by gaseous compounds, but also by aerosols and particulate matter (PM). These extremely fine particles enter and damage the lungs; from them, ultrafine particles can spread across the body through the blood cells and cause symptoms of inflammation. While these risks are being debated and researched actively around the world, it is still not known which compounds actually cause harm.

    As a result, there is a great need for more specific data on long-term measurements. Fast analytical methods and real-time measurements of concentrations of chemical compounds in ambient air are important and should make it possible to better understand the circumstances and effects.

    For optimal air quality monitoring, the gas and aerosol composition of the surrounding air has to be analyzed practically simultaneously as well as continuously, which is possible via inline analysis with ion chromatography.

    Metrohm Process Analytics offers the 2060 MARGA (Monitor for AeRosols and Gases in ambient Air) which thanks to its dual-channel ion chromatograph, can automatically analyze the ions from the collected gas and aerosol samples.

    If you want to learn more background behind the development of the 2060 MARGA, check out our previous blog post: History of Metrohm IC – Part 5.

    For a full list of free downloadable 2060 IC applications, visit our website and check out the Metrohm Application Finder!

    Free Application Notes

    For the 2060 IC Process Analyzer

    Post written by Andrea Ferreira, Technical Writer at Metrohm Applikon, Schiedam, The Netherlands.