Chemical industry
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TOC determination in hydrochloric acid TOC determination in nitric acid TOC determination in sulfuric acid TOC determination in brine solution TOC determination in sodium hydroxide solution TOC determination in soda solution The most commonly used compound in the chemical industry is water – not only as a solvent in processing, but also as an energy carrier in the cooling or heating cycle. As vast amounts of water are needed, chemical industries are often located close to large bodies of flowing water. Water used as processing water or as cooling water is cleaned and subsequently led back...

Sum parameter – Total Organic Carbon TOC – Determination in hydrochloric acid Acids, in particular concentrated hydrochloric acid, represent a large group of inorganic chemicals frequently used in the chemical industry. TOC determination in concentrated hydrochloric acid poses an enormous challenge to the analyzers that are used for this purpose. In general, it is possible to greatly dilute the substance to be analyzed in order to eliminate matrix interferences. But sometimes it is necessary to achieve very low limits of detection (with reference to 37% hydrochloric acid) of 1 mg/L. ■ TOC...

To investigate matrix influences, a potassium hydrogen phthalate solution was subsequently added to the 18.5% hydrochloric acid solution to increase the TOC by 5 ppm (Figure 3 and Table 1). The relative standard deviation over all measurements was 3.4%. The following graph shows the progression of the TOC values of the hydrochloric acid injections. Blank values and standards (10 ppm) were alternately measured between the individual measurements. Figure 3 and Table 1 show the results of the individual measurements of the hydrochloric acid as well as the measurements of the spiked...

SHIMADZU Excellence in Science Sum parameter - Total Organic Carbon Application NewsTOC - Determination in nitric acid No. SCA-130-302 Organic contaminants present in basic chemicals may constitute the impurities in products. This is why quality control of the reactants is indispensable. The determination of organic contaminations in concentrated nitric acid (69%) becomes a challenge when the required detection limit does not allow large dilution steps. An example is the TOC determination in a 69% HNO3 solution with a detection limit of < 10 mg/L. ■ Sample preparation For sample...

The use of suitable gas washers (scrubbers) enables reproducible TOC measurements in concentrated nitric acid. SHIMADZU Shimadzu Europa GmbH For Research Use Only. Not for use in diagnostic procedures. The content of this publication shall not be reproduced, altered or sold for any commercial purpose without the written approval of Shimadzu. The information contained herein is provided to you "as is' without warranty of any kind including without limitation warranties as to its accuracy or completeness Shimadzu does not assume any responsibility or liability for any damage, whether direct...

SHIMADZU Excellence in Science Sum parameter - Total Organic Carbon Application NewsTOC - Determination in sulfuric acid NO. SCA-130-303 Acids are a group of frequently used inorganic chemicals used in the chemical industry. In particular, sulfuric acid is used in a wide range of applications. Sulfuric acid in a concentration range to 1%.can be directly measured using a TOC-L analyzer Higher sulfuric acid concentrations can lead to tailing and, consequently to increased measurement values because high sulfate concentrations (> 5000 mg/L) can lead to the formation of large amounts of...

The system is calibrated using the automatic dilution function in the range of 0.5 mg/L to 10 mg/L. ■Result The duplicate determination of sulfuric acid yielded the following results: The sulfuric acid fulfilled the required purity criteria of TOC < 10 mg/L. ■ Kit for high-salt samples For the determination, a TOC-Lcph equipped with a kit for high salt loads was used. The kit consists of a special catalyst tube, a special mixture of various catalyst beads and a ceramics grid, which replaces the platinum net. Sample acidification when using the high-salt kit, is carried out with sulfuric...

SHIMADZU Excellence in Science Sum parameter - Total Organic Carbon Application NewsTOC - Determination in brines NO. SCA-130-304 Tab. Melting point of different salts The determination in difficult matrices, such as brines or heavily contaminated wastewaters, presents a special challenge for TOC analyzers. In the chemical industry, brines with a salt load (NaCl) of up to 28% are used for chlor-alkali electrolysis. For this process it is important to know the TOC content. The unique feature of this application does not inherently lie in the conversion of the carbon components to carbon...

For the analysis a TOC-Lcph equipped with a kit for high salt loads was used. The system is calibrated using the automated dilution function in the range of 0.5 mg/L to 10 mg/L. ■ Result The duplicate determination of the TOC analysis yielded the following results: ■ Stability test In this test, the long-term stability of the combustion system was tested. The system was calibrated to 10 mg/L with an injection volume of 50 pL. A 28% NaCl solution was prepared and spiked with a KHP solution to obtain a 5 mg/L TOC solution and a 15% sulfuric acid solution was added. Initially, a blank value...

SHIMADZU Excellence in Science Sum parameter - Total Organic Carbon TOC - Determination in sodium hydroxide solution Application News NO. SCA-130-305 Compound (Concentration) Organic contaminants in basic chemicals may lead to impurities in the products. Therefore, quality control of the reactants is necessary. The TOC determination in sodium hydroxide can lead to various problems. The catalyst and the combustion tube wear out very rapidly. This, in turn, will lower the sensitivity at an equally fast rate and leads to very poor reproducibilities. NaOH can also absorb CO2 from...

Application News The sodium hydroxide met the required purity criteria of < 10 mg/L TOC. SHIMADZU Shimadzu Europa GmbH For Research Use Only. Not for use in diagnostic procedures. The content of this publication shall not be reproduced, altered or sold for any commercial purpose without the written approval of Shimadzu. The information contained herein is provided to you "as is’ without warranty of any kind including without limitation warranties as to its accuracy or completeness. Shimadzu does not assume any responsibility or liability for any damage, whether direct or indirect, relating...