TY - CONF A1 - Meyer, Klas A1 - Kipphardt, Heinrich A1 - Maiwald, Michael T1 - High-pressure qNMR spectroscopy in condensed- and gas-phase towards determination of impurities and compositions of gas mixtures N2 - Recent technical developments of NMR instruments such as in acquisition electronics and probe design allow detection limits of components in liquid mixtures in the lower ppm range (approx.. 5–10 ppm amount of substance). The major advantage of quantitative NMR spectroscopy (qNMR) is that it is a direct ratio method of analysis without the need of calibration. This means that the signal for a specific NMR-active nucleus (e.g., a proton) in an analyte can be compared and quantified by reference to a different nucleus of a separate compound, comparable to a counting of spins in the active volume of the spectrometer. A special application of qNMR in technical mixtures is the observation in the gas phase, which is rarely applied compared to liquid and solid NMR studies. Because of the low density it results in a reduced sensitivity, which can be improved by applying pressure. Therefore a high-pressure NMR setup was developed based on a commercially available NMR tube made of zirconia. This is currently tested up to 20 MPa, but can be extended up to 100 MPa with regard to pressure rating of its components. This work shows results of gas-phase application on natural-gas like reference gas mixtures produced at BAM, as well as investigations on liquefied petroleum gas mixtures (LPG) with high accuracy provided in constant-pressure piston cylinders. T2 - 35th Meeting of the CCQM-Gas Analysis Working Group, Workshop "Cutting edge research for gas metrology" CY - Caparica, Portugal DA - 13.10.2016 KW - Quantitative NMR spectroscopy KW - Gas-phase NMR KW - Reference gas mixtures KW - Liquefied petroleum gas PY - 2016 AN - OPUS4-37803 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meyer, Klas A1 - Rademann, K. A1 - Maiwald, Michael T1 - Quantitative NMR spectroscopy for gas metrology – applications in liquefied petroleum gases N2 - The field of gas metrology is dealing with the development and improvement of gas analytical methods, as well as production of highly accurate primary reference standards. These are prepared at national metrological institutes (NMI) and represent the highest national level of traceability. Used for certification of secondary standards provided by specialty gas distributors these are very important for a high number of industrial sectors, which have to proof traceability due to legal or regulatory affairs, e.g., natural gas suppliers. Thus, improvements in the production and certification of these mixtures will have a direct influence on gas industry. Due to its direct correlation to the number of spins within active sample volume quantitative NMR spectroscopy (qNMR) is a highly promising method with absolute comparison abilities in complex systems. Especially for liquefied petroleum gases (LPG) it has the ability of studying the unmodified sample at same conditions like in the cylinder. In contrast to gas chromatography no preparation steps and no changes like evaporation of the sample are necessary. In this work we show the most recent results of our investigations on highly accurate LPG mixtures provided in constant-pressure piston cylinders. A dynamic pressure-resistant setup allows for sampling and circulation of the samples to ensure a homogeneous withdrawal from the cylinder. This is presented on examples of a commercial multicomponent LPG mixture obtained from specialty gas distributor, as well as two cylinders from the key comparison CCQM-K119 at highest level of international metrology. T2 - 5th Panic - Practical Applications of NMR in Industry Conferece CY - Hilton Head Island, SC 29928, USA DA - 20.02.2017 KW - Quantitative NMR spectroscopy KW - Gas metrology KW - Liquefied petroleum gas PY - 2017 AN - OPUS4-39234 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meyer, Klas T1 - High-pressure qNMR spectroscopy in condensed- and gas-phase towards determination of impurities and compositions of gas mixtures N2 - Recent technical developments of NMR instruments such as in acquisition electronics and probe design allow detection limits of components in liquid mixtures in the lower ppm range (approx.. 5–10ppm amount of substance). The major advantage of quantitative NMR spectroscopy (qNMR) is that it is a direct ratio method of analysis without the need of calibration. This means that the signal for a specific NMR-active nucleus (e.g., a proton) in an analyte can be compared and quantified by reference to a different nucleus of a separate compound, comparable to a counting of spins in the active volume of the spectrometer. A special application of qNMR in technical mixtures is the observation in the gas phase, which is rarely applied compared to liquid and solid NMR studies. Because of the low density it results in a reduced sensitivity, which can be improved by applying pressure. Therefore a high-pressure NMR setup was developed based on a commercially available NMR tube made of zirconia. This is currently tested up to 20 MPa, but can be extended up to 100 MPa with regard to pressure rating of its components. This work shows results of gas-phase application on natural-gas like reference gas mixtures produced at BAM, as well as investigations on liquefied petroleum gas mixtures (LPG) with high accuracy provided in constant pressure piston cylinders. T2 - qNMR Summit 2017 CY - Berlin, Germany DA - 16.03.2017 KW - Quantitative NMR spectroscopy KW - Gas-phase NMR KW - Reference gas mixtures KW - Liquefied petroleum gas PY - 2017 AN - OPUS4-39425 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -