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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.

Although the process of building, validating and using a method is well-defined through software, the robustness of the method is dependent on proper practice of sampling, validation, and method maintenance. In this document, we will detail the recommended practices for using the multivariate method with NanoRam-1064. These practices are recommended for end users who are in the pharmaceutical environment, and can expand to other industries as well. This document aims to serve as a general reference for NanoRam-1064 users who would like to build an SOP for method development, validation and implementation.

Raman spectroscopy’s use for process analytics in the pharmaceutical and chemical industries continues to grow due to its nondestructive measurements, fast analysis times, and ability to do both qualitative and quantitative analysis. Spectral preprocessing algorithms are routinely applied to quantitative spectroscopic data in order to enhance spectral features while minimizing variability unrelated to the analyte in question. In this technical note we discuss the main preprocessing options pertinent to Raman spectroscopy with real applications examples, and to review the algorithms available in B&W Tek and Metrohm software so that the reader becomes comfortable applying them to build Raman quantitative models.

In this poster a convenient direct injection suppressed ion chromatographic method for determining chloride and sulfate in denatured ethanol samples according to ASTM D7319 is presented.

Quality and process control of biofuels require straightforward, fast and accurate analysis methods. Ion chromatography (IC) is at the leading edge of this effort. Traces of anions in a gasoline/ethanol blend can accurately be determined in the sub-ppb range after Metrohm Inline Matrix Elimination using anion chromatography with conductivity detection after sequential suppression. While the analyte anions are retained on the preconcentration column, the interfering organic gasoline/bioethanol matrix is washed away.Detrimental alkali metals and water-extractable alkaline earth metals in biodiesel are determined in the sub-ppm range using cation chromatography with direct conductivity detection applying automated extraction with nitric acid and subsequent Metrohm Inline Dialysis. Unlike high-molecular substances, ions in the high-ionic strength matrix diffuse through a membrane into the low-ionic water acceptor solution. In biogas reactor samples, low-molecular-weight organic acids stem from the biodegradation of organic matter. Their profile allows important conclusions concerning conversion in the anaerobic digestion reaction. Volatile fatty acids and lactate can be accurately determined by using ion-exclusion chromatography with suppressed conductivity detection after inline dialysis or filtration.

The analytical challenge treated by the present work consists in detecting sub-ppm quantities of bromide, sulfate, aliphatic monocarboxylic acids and several alkaline earth metals in the presence of very high concentrations of sodium and chloride. Bromide, sulfate, acetate and butyrate can be reliably determined by suppressed conductivity detection. Due to matrix effects, propionate can only be detected qualitatively. This drawback can be overcome by coupling the ion chromatograph (IC) to a mass spectrometric (MS) detector. This results in reduced matrix interferences and significantly enhanced sensitivities. The cations magnesium, barium and strontium are determined by non-suppressed conductivity detection.

Several testing methods such as the determination of the acid and the iodine numbers in biodiesel as well as the quantification of sulfate and chloride in bioethanol are described.

Commercially available fuels are complex mixtures of hundreds of different hydrocarbons. For the calibration of the test engines or advanced experimental and computational research they are modeled by means of multicomponent surrogate mixtures that adequately represent the desired physical and chemical characteristics. By definition, every octane and cetane number corresponds to a specific mixing ratio of primary reference fuels (PRFs). Based on this information, the tiamoTM controlled automatic dosing device prepares the surrogate mixtures. The setup drastically minimizes time-consuming and error-prone manual preparation steps and the contact with hazardous solvents. Additionally, precise and accurate results are displayed on customizable reports that fully comply with all current GLP and GMP requirements.

The presence of copper in fuel ethanol blends has gained considerable attention, since Cu2+ catalyzes oxidative reactions in gasoline leading to a deterioration of olefins and the formation of gum. Anodic stripping voltammetry (ASV), one of the most sensitive and accurate techniques for trace-metal analysis, has been demonstrated for the determination of Cu(II) in ethanol/gasoline blends without any sample pretreatment. Copper ions are first electrodeposited onto the surface of a hanging mercury drop electrode (HMDE) before the amalgamated copper is quantitatively stripped (anodically dissolved), a current-voltage curve being recorded.Experimental conditions such as deposition time and potential as well as the suitable electrolyte and reference electrode were determined in preliminary experiments. For synthetic samples spiked with Cu2+ (5…100 µg/L), recovery rates between 96 and 112% were obtained. The copper-spiked E85 sample provided a recovery of 100%. The relative standard deviations for Cu2+ concentrations of 5 µg/L and above were 8.0 and 5.5% respectively. Using a preconcentration time of 60 s at -0.7 V versus Ag/AgCl, a linear range of 0…500 µg/L with a detection limit of 2 µg/L was obtained.

This poster provides an overview of ion chromatographic methods combined with inline sample preparation for the determination of anions and water-extractable cations in biofuels. In addition, the determination of the oxidation stability is described.