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A method for the potentiometric determination of CaCO3 in cement raw meal is described, in which the accurately weighed-out sample is treated with HCl, heated to boiling and the excess HCl is then back-titrated with NaOH.

As much as the many types of cement may differ from one another, the characteristic that all of them have in common is the presence of the elements calcium, magnesium, iron, aluminum and silicon.Calcium, magnesium, iron and aluminum can be determined using various indicators following digestion of the cement sample using photometric titration with the Optrode at 610 nm. The determination of silicon, on the other hand, is gravimetric.

The potassium (or ammonium) ion is precipitated with sodium tetraphenyl borate, and the excess of this reagent back-titrated against the thallous(I) ion, using biamperometric endpoint detection. Ammonium can either be titrated together in an acid solution, or driven off by previous boiling in an alkaline solution. Methods are given for determining potassium in the presence of large excesses of sodium, ammonium, calcium, and magnesium.

This Bulletin describes the complexometric potentiometric titration of metal ions. An ion-selective copper electrode is used to indicate the endpoint of the titration. Since this electrode does not respond directly to complexing agents, the corresponding Cu complex is added to the solution. With the described electrode, it is possible to determine water hardness and to analyze metal concentrations in electroplating baths, metal salts, minerals, and ores. The following metal ions have been determined: Al3+, Ba2+, Bi3+, Ca2+, Co2+, Fe3+, Mg2+, Ni2+, Pb2+, Sr2+, and Zn2+.

Potentiometric titration is an accurate method for determining chloride content. For detailed instructions and troubleshooting tips, download our Application Bulletin.

In the application note AN-EIS-004 on equivalent circuit models, an overview of the different circuit elements that are used to build an equivalent circuit model was given. After identifying a suitable model for the system under investigation, the next step in the data analysis is estimation of the model parameters. This is done by the non-linear regression of the model to the data. Most impedance systems come with a data-fitting program. In this application note, the way NOVA is uses to fit the data is shown.

In this application note, the advantage of recording the raw time domain data for each individual frequency during an electrochemical impedance measurement is described.

Electrochemical impedance spectroscopy (EIS) is a powerful technique which provides information about the processes occurring at the electrode-electrolyte interface. The data collected with EIS are modeled with a suitable electrical equivalent circuit. The fitting procedure will change the values of the parameters until the mathematical function matches the experimental data within a certain margin of error. In this Application Note, some suggestions are given in order to get acceptable initial parameters and to perform an accurate fitting.

Determination of fluoride in cement or clinker by direct potentiometry with the F-ISE.

The water content of lime is determined according to Karl Fischer using the oven method (150 °C).

The water content in Ca carbonate is determined by volumetric Karl Fischer titration.

Determination of fluoride and chloride in gypsum using anion chromatography and subsequent direct conductometric detection.

Determination of sulfate in hydrochloric acid digest of gypsum using anion chromatography with direct conductometric detection.

Solids used in road construction were analyzed with a hand-held Raman spectrometer. The materials examined are conventional pigments and resins, e.g., CaCO3, TiO2 and DEGALAN®. The measured spectra differ considerably from one another. In order to assess the main differences between the chemical structures, the peaks of the spectra were assigned to the functional groups that generated them.

Determination of chromate in cement using anion chromatography with conductivity detection after chemical suppression.

FDG gypsum originates from flue gas desulfurization systems in power plants. VGB-M 701 E (2008) describes aqueous extraction methods for determining chloride in FDG gypsum using ion chromatography. The sample preparation described in the VGB permits the determination of other anions besides chloride.

Determination of trace chloride in cement and clinker by potentiometric titration with silver nitrate using the Ag-Titrode.

Determination of sulfate in cement by indirect potentiometric titration with EDTA using platinum and tungsten electrodes.

Determination of the sum of calcium and magnesium in cement by photometric titration with EDTA using the 610 nm Spectrode.

Determination of aluminum in cement by photometric back-titration of the EDTA excess with zinc sulfate using the 610 nm Spectrode.

This Application Note describes the photometric determination of sulfate in aqueous solutions using the Optrode (520 nm). Sulfate is precipitated with an excess of barium chloride solution. Excess barium is subsequently titrated with EDTA.

This Application Note describes the photometric determination of aluminum in cement using the Optrode (574 nm). Following breakdown of the cement sample, the dissolved aluminum is titrated with EDTA. The excess EDTA is titrated back with zinc sulfate solution.

This Application Note covers the photometric determination of calcium in cement using the Optrode (610 nm). After digestion of the cement sample, calcium is titrated with EDTA to the murexide endpoint.

This Application Note describes the digestion of a cement sample and the photometric determination of iron in accordance with DIN EN 196-2 by means of Optrode at 610 nm. Sulfosalicylic acid is used as the indicator and EDTA as the titrant for the determination.

This Application Note is devoted to the photometric determination of magnesium in cement using the Optrode (610 nm). After digestion of a sample aliquot, the magnesium content is determined using EDTA titration.

This Application Note describes the fully automated complexometric determination of total iron in cement with a copper ion-selective electrode.

Cr(VI) is determined at the HMDE in an electrolyte containing ethylenediamine and acetate. Because Cr(III) is electrochemically inactive, all Cr has to be oxidised prior to analysis.

The concentration of Cr(VI) in cement is determined in tartrate electrolyte after acid extraction of the sample.

This article describes the coupling of ion chromatography with mass spectrometry (IC-MS) and plasma mass spectrometry (IC-ICP/MS) for the trace analysis of potentially hazardous compounds in the environment.