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More strict regulations paired with more complex products have increased testing complexity in the paint and coating industry. Therefore, producers ask for more powerful, safe and sustainable analytical methods. Testing by Vis-NIR spectroscopy is a sustainable and costefficient alternative to many wet chemical methods. This white paper describes how Vis-NIR spectroscopy improves testing procedures for various analyses during the formulation and production of paint and coatings in an economic and ecological way.Key words: testing, sustainable, VOC, paint, coating, binders, resins, additives, pigments, solvents

Propylene oxide (PO) is a major industrial product used in assorted industrial applications, mainly for the production of polyols (the building blocks for polyurethane plastics). Several production methods exist, with and without co-products. This white paper lays out opportunities to optimize PO production for safer and more efficient processes, higher quality products, and substantial time savings by using online process analysis instead of laboratory measurements.

Ion chromatography mass spectrometry (IC-MS) is a powerful tool that can handle many challenging analytical tasks which cannot be performed adequately by IC alone. IC-MS is a robust, sensitive, and selective technique used for the determination of polar contaminants like inorganic anions, organic acids, haloacetic acids, oxyhalides, or alkali and alkaline earth metals. After separation of the sample components via IC, mass selective detection guarantees peak identity with low detection limits. The inclusion of automated Metrohm Inline Sample Preparation (MISP) allows not only water samples, but also chemicals, organic solvents, or post-explosion residues to be readily analyzed without need for extensive manual laboratory work. This White Paper explains the benefits of IC-MS over IC in certain cases, the hyphenation of IC and different MS systems, as well as related norms and standards.

This White Paper focuses on selected IC-MS applications for the straightforward identification and quantification of organic acids and inorganic anions in different matrices.

In modern days, a new breed of energetic (explosive) materials is emerging. Traditional aromatic nitrates are still in use, but there is dire need of analytical techniques for energetic materials in the chemical class of peroxides, azo etc. This presentation will demonstrate the use of a modern HPLC system with traditional detector (DAD) and also coupled with mass spectrometry for the analysis of abovementioned various classes of energetic materials.

Raman spectroscopy is an advantageous analytical tool that allows for the measurement of molecular structure and identifying chemical composition of materials based on the rotational and vibrational modes of a molecule. With advanced technology and an optimized optical design, the B&W Tek BAC102 series E-grade probe can access lower frequency modes down to 65 cm-1, providing key information for applications in protein characterization, polymorph detection, and identification, along with material phase and structure determination.

Allowing non-destructive chemical identification through opaque materials, award-winning STRam represents an evolution in Raman technology.

Raman spectroscopy is used for material characterization by analyzing molecular or crystal symmetrical vibrations and rotations that are excited by a laser, and exhibit vibrations specific to the molecular bonds and crystal arrangements in the molecules. Raman technology is a valuable tool in distinguishing different polymorphs. Examples of portable Raman spectroscopy for identification of polymorphs and in monitoring the polymorphic transiton of citric acid and its hydrated form are presented.

This article demonstrates the utility of portable Raman spectroscopy as a versatile tool for process analytical technology (PAT) for raw material identification, in-situ monitoring of reactions in developing active pharmaceutical ingredients (APIs), and for real-time process monitoring. Raw material identification is done for verification of starting materials as required by PIC/S and cGMP, and can be readily done with handheld Raman. Portable Raman systems allow users to make measurements to bring process understanding and also provide proof of concept for the Raman measurements to be implemented in pilot plants or large-scale production sites. For known reactions which are repetitively performed or for continuous online process monitoring of reactions, Raman provides a convenient solution for process understanding and the basis for process control.

Ternary mixtures of aqueous sugar solutions are measured and multivariate models of the concentration of analytes developed using BWIQ software.

In this case study, a suspected counterfeit Adderall pill was measured directly with a TacticID Mobile using a point-and-shoot adapter. The spectra of the suspected couterfeit pill was found to contain cellulose and caffeine, but not the active ingredient. The TacticiD Mobile with 1064-nm laser excitation provides fluorescence suppression, giving those on the front lines a tool in the fight against dangerous counterfeit drugs.

Raman spectroscopy is a valuable tool for the characterization of carbon nanomaterials due to its selectivity, speed, and ability to measure samples nondestructively. Carbon materials typically have simple Raman spectra, but they contain a wealth of information about internal microcrystalline structures in peak position, shape, and relative intensity.

This Bulletin describes three potentiometric, one photometric, one thermometric and one conductometric titration method for sulfate determination. The question of which indication method is the most suitable depends primarily on the sample matrix.Method 1: Precipitation as barium sulfate and back titration of the Ba2+ surplus with EGTA. Use of the ion-selective calcium electrode as indicator electrode.Method 2: As with Method 1, although with the electrode combination tungsten/platinum.Method 3: Precipitation titration in semi-aqueous solution with lead nitrate in accordance with the European Pharmacopoeia using the ion-selective lead electrode as indicator electrode.Method 4: Photometric titration with lead nitrate, dithizone indicator and the Optrode 610 nm, particularly suitable for low concentrations (up to 5 mg SO42- in the sample solution).Method 5: Thermometric precipitation titration with Ba2+ in aqueous solution, particularly suitable for fertilizers.Method 6: Conductometric titration with barium acetate in accordance with DIN 53127

A potentiometric, nonaqueous method is described for analyzing nitrating acid using cyclohexylamine as titrant. Both sulfuric and nitric acid can be determined quantitatively.

Halides interfere with most determinations of mercury or silver. However, if mercury or silver is titrated with sulfide ions, extremely insoluble sulfides are formed.A simple method is described that allows the direct titration of mercury(II) or silver(I) compounds in the presence of halides. The potentiometric titration takes place under alkaline conditions using thioacetamide as the titrant after formation of the EDTA complex.Organic compounds that are insoluble in alkaline EDTA can also be titrated after a Schoeniger digestion.

Bromide is removed from the sample as BrCN by distillation. The BrCN is absorbed in sodium hydroxide solution and decomposed with concentrated sulfuric acid, then the released bromide ions are determined by potentiometric titration with silver nitrate solution. Iodide does not interfere with the determination.Iodide is oxidized to iodate by hypobromite. After destruction of the excess hypobromite, the potentiometric titration (of the iodine released from iodate) is carried out with sodium thiosulfate solution. Bromide does not interfere, even in great excess.The described methods allow the determination of bromide and iodide in the presence of a large excess of chloride (e.g., in brine, seawater, sodium chloride, etc.).

After acid digestion, the sample solution is neutralized with sodium hydroxide to form sodium dihydrogen phosphate. An excess of lanthanum nitrate is added and the released nitric acid is then titrated with sodium hydroxide solution.NaH2PO4 + La(NO3)3 → LaPO4 + 2 HNO3 + NaNO3This determination method is suitable for higher phosphate concentrations.

Application Bulletin AB-076 contains a description of the polarographic determination of low concentrations (1–100 mg/L) of NTA and EDTA in bodies of water. NTA, EDTA and citrate have gained in importance as complexing agents and builders due to the fact that the laws of some countries have made it necessary to find a substitute for phosphates in detergents.This Bulletin describes the determination of larger quantities of complexing agents in detergents using potentiometric titration. The ion-selective copper electrode (Cu-ISE) is used here as the indicator electrode. The determination of complexing agents is not disturbed by the other constituents often present in detergents.

The metals Cd, Co, Cu, Fe, Ni, Pb, and Zn are determined in the sub-ppb range (limit of detection 0.05 µg/L) by means of stripping voltammetry. The DP-ASV method is used for Cd, Cu, Pb, and Zn whereas Co, Ni, and Fe are determined by means of the DP-CSV method (dimethylglyoxime or catechol complexes).Use of the VA Processor and the sample changer allows automatic determination of the above metal ions in one solution. The method has been specially developed for trace analysis in the manufacture of semiconductor chips based on silicon. It can naturally also be employed successfully in environmental analysis.

The two potentiometric titration methods described here allow the determination of the content of commercial betaine solutions. Neither method is suitable for determining the betaine content of formulations. The possibilities and limits of both methods are described and distinctive features and possible sources of interference are mentioned. The Bulletin explains the most important theoretical principles and is intended to help users to develop their own product-specific titration methods.

Phosphate can be rapidly and easily titrated thermometrically using a standard solution of Mg2+ as titrant. The phosphate-containing solution is basified and buffered with NH3/NH4Cl solution before titration. The formation of insoluble MgNH4PO4 is exothermic. The method is a titrimetric adaptation of a classical gravimetric procedure. This bulletin deals with the determination of phosphate in phosphoric acid and granular fertilizers such as MAP (monoammonium phosphate), DAP (diammonium phosphate) and TSP (triple superphosphate). Results are reported as percentage of P and P2O5.

This Bulletin describes fluoride determination in various matrices with the help of the ion-selective fluoride electrode (F-ISE). The F-ISE is comprised of a lanthanum fluoride crystal and exhibits a response in accordance with the Nernst equation across a wide range of fluoride concentrations.The first part of this Bulletin contains notes regarding the handling and care of the electrode and the actual fluoride determination itself. The second part demonstrates the direct determination of fluoride with the standard addition technique in table salt, toothpaste and mouthwash.

It has been known for years that consuming too much nitrates from foodstuffs can result in cyanosis, particularly for small children and susceptible adults. According to the WHO standard, the hazard level lies at a mass concentration c(NO3-) ≥ 50 mg/L. However, more recent studies have shown that when nitrate concentrations in the human body are too high, they can (via nitrite) result in the formation of carcinogenic and even more hazardous nitrosamines.Known photometric methods for the determination of the nitrate anion are time-consuming and prone to a wide range of interferences. With nitrate analysis continually increasing in importance, the demand for a selective, rapid, and relatively accurate method has also increased. Such a method is described in this Application Bulletin. The Appendix contains a cselection of application examples where nitrate concentrations have been determined in water samples, soil extracts, fertilizers, vegetables, and beverages.

Determination of sodium, potassium, and silica values in sodium and potassium silicates.

Hypochlorite ions react with bromide ions to form hypobromite ions, which in turn rapidly oxidize ammonium ions to nitrogen. Hypobromite reacts more rapidly with ammonium than hypochlorite, and is formed in situ (Vogel, 1961). The titration is carried out with in a solution containing bromide and bicarbonate.

Determination of the sulfate content of wet process phosphoric acid.

Determination of acetic anhydride in the presence of acetic acid in acylation mixtures.

Determination of low levels of sulfate (to approximately 20mg/L SO42-) by thermometric titration.

Hydrogen peroxide solutions can be determined through thermometric endpoint titration (TET) using iodometry. Iodide is oxidized to become iodine, which is then titrated with a standard thiosulfate solution in an exothermic reaction.

Metal-organic compounds are commonly used in organic chemistry, for example as Grignard reagents or as strong bases (e.g., butyl lithium compounds). The knowledge of the exact content of reactive species allows to better plan the required amounts for reactions preventing the waste of material or too low yields.This Application Note describes the analysis of metal organics by thermometric titration using 2-butanol as titrant. Due to the strongly exothermic nature of the reaction between 2-butanol with metal-organic compounds, a fast and quantitative analysis of these substances is possible.

Determination of tar acids in coal tar products. This procedure may also be applied to the determination of a range of weakly acidic organic compounds such as carboxylic acids, hydroxy acids, phenols, phenolic acids, keto-enols, imides, and aromatic nitro compounds.11 Vaughan, G. A. Thermometric and Enthalpimetric Titrimetry. Van Nostrand Reinhold Co. Ltd (1973)

Determination of ammonium ions in ammonium salts and mixtures containing ammonium ion.

Sulfur is a secondary macronutrient for plants and is essential for chloroplast growth and function. In fertilizers, sulfur is usually provided in the form of sulfate. Traditionally the sulfate content is determined gravimetrically by precipitation with barium. The drawback of this method is that it requires numerous time consuming and laborious analysis steps.In this Application Note, an alternative method is presented, where sulfate is determined by a precipitation titration with barium chloride. Various solid and liquid NPK fertilizers with sulfur contents between 1 and 8% were analyzed. The analysis of sulfate in fertilizers by thermometric titration requires no sample preparation at all for liquid NPK fertilizers, and only minimal sample preparation for solid NPK fertilizers. One determination takes about 3 minutes only. To increase the sensitivity of the method, the samples are spiked with a standard sulfuric acid solution, which is then considered when calculating the result.

Determination of sulfate and total acids in a nitrating mixture.

Determination of phosphoric and nitric acids in liquors from the Nitrophos fertilizer manufacturing process.

A direct thermometric titration (TET) with 2 mol/L NaOH is used to determine the HF, NH4F, and maleic acid (C4H4O4) contents of acid cleaning solutions. Three endpoints (EPs) are obtained, which may be assigned as follows:EP1: C4H4O4 (pKa1 = 1.9), HF (pKa = 3.17)EP2: C4H4O4 (pKa2 = 6.07)EP2: NH4F (pKa = 8.2)The HF content is determined by subtracting the difference (EP2-EP1) from EP1.

Potassium is a primary macronutrient for plants, as it plays an important role in water regulation as well as plant growth. In NPK fertilizers, potassium is present besides nitrogen and phosphorus, which are the other two primary macronutrients. Knowing the quality and content of a NPK fertilizer allows an optimal fertilizer management for a planned culture, saving costs and increasing profitability.Traditionally potassium is determined gravimetrically or by flame photometry. In this Application Note, an alternative method is presented, where potassium is determined a precipitation titration. Various solid and liquid NPK fertilizers with potassium contents between 10 and 27% were analyzed. After the removal of any present ammonia, the potassium can be determined reliably in about 5 minutes.

This application describes the determination of fluoride, chloride, bromide and sulfur (as sulfate) in an ethanol standard solution with halo organic (4-halogen benzoic acids; F, Cl and Br) and sulfur organic compounds (3-(Cyclohexylamino)-1-propanesulfonic acid) by means of Metrohm Combustion Ion Chromatography with flame sensor and Inline Matrix Elimination.Keyword: pyrohydrolysis

Determination of fluoride, chloride, bromide and sulfate in residual solvent using combustion digestion as sample preparation and subsequent anion chromatography with conductivity detection following sequential suppression. The analysis is significant for use in dividing waste products into non-halogenated and halogenated solvents.Keyword: pyrohydrolysis

Near-infrared spectroscopy (NIRS) was used as an analysis method for quality control of soap noodles. Quantitative models for the determination of Total Fatty Matter, Iodine Number, and C8–C14 were developed, enabling fast and reliable quality control.

Packaging has become an indispensable part in the food manufacturing process. To improve the appearance and properties of the packaging, a wide variety of coatings and inks are used. Different additives enhance rheological properties, control the wetting dispersion, or in the case of wax increase abrasion resistance. The regulations of these coatings in food packaging applications are very strict in some countries, creating the need for close monitoring of the production process.A fast, reliable, and simple to use solution for quantifying rheological additives and wax in such coatings is Visible-Near Infrared Spectroscopy (Vis-NIRS). Both parameters are determined simultaneously by Vis-NIRS in less than a minute.

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.

This Application Note describes the simultaneous determination of the four most important analysis parameters of paint dryers – cobalt and solids contents, specific weight and viscosity – using a VIS-NIR analyzer. The visible range correlates with the metal content, while the NIR region provides the specific weight, viscosity and solids content.

Toxic and corrosive chemicals such as p-toluenesulfonyl isocyanate (TSI) and tetrabutylammonium hydroxide are used for the Hydroxyl Number analysis of polyols by titration according to ASTM D4274-16. This application note demonstrates how the XDS RapidLiquid Analyzer operating in the visible and near-infrared spectral region (Vis-NIR) provides a cost-efficient and fast solution for the determination of the hydroxyl (OH) number of polyols. With no sample preparation or chemicals needed, Vis-NIR spectroscopy allows for the analysis of polyols in less than a minute.

Raman spectroscopy with PLS modeling enables rapid, accurate, nondestructive quantification of the total phosphate content in solution with minimal sample preparation.

Raman spectroscopy is a fast alternative method to detect phosphate and sulfate species in solution for optimized phosphorus fertilizer production and improved product quality.

Compared to potentiometric titration, Raman spectroscopy is a rapid, accurate, and reliable secondary method for estimating the amine value (AV) of epoxy hardeners.

Determination of zinc, sodium, ammonium, and manganese in the presence of magnesium and calcium in an extract of a zinc compound using cation chromatography with direct conductivity detection.

Determination of trimethylamine in hydrogen peroxide (31 %) using cation chromatography with direct conductivity detection after inline matrix elimination, inline preconcentration, and inline calibration.

Determination of strontium and barium in monoethylene glycol using cation chromatography with direct conductivity detection.