Future Trends in Process Analytical Chemistry

Bakeev, Katherine A.

doi:10.1002/9780470988459.ch12

Cited by 14 publications

(30 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The PLS models reported in Table were obtained by following the procedure outlined in Figure . If necessary, the wavelength interval was narrowed slightly to avoid noise introduced by the Savitzky–Golay , pretreatments in the neighborhood of the THF absorption band. Five different pretreatments , were tested: two-point baseline correction (BC) based on an area without analyte absorption, first derivative (Savitzky–Golay), second derivative (Savitzky–Golay), , multiplicative scatter correction (MSC) and standard normal variate (SNV).…”

Section: Resultsmentioning

confidence: 99%

“…Then, a projection to latent structures (PLS, also known as partial least-squares) regression model was built based on a calibration data set. Leave-one-out cross-validation was used to generate a standard error of cross-validation (SECV) plot, from which the minimum number of significant latent variables was selected to avoid model overfitting. The SECV was compared for the different pretreatments tested and the best model was validated against an independent validation data set, obtaining a standard error of prediction (SEP).…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Monitoring and Control of a Continuous Grignard Reaction for the Synthesis of an Active Pharmaceutical Ingredient Intermediate Using Inline NIR spectroscopy

Padrell

Nielsen

Pedersen

et al. 2012

Org. Process Res. Dev.

View full text Add to dashboard Cite

Inline near-infrared (NIR) spectroscopy has been used to monitor a continuous synthesis of an active pharmaceutical ingredient (API) intermediate by a Grignard alkylation reaction. The reaction between a ketone substrate and allylmagnesium chloride may form significant impurities with excess feeding of the Grignard reagent beyond the stoichiometric ratio. On the other hand, limiting this reagent would imply a loss in yield. Therefore, accurate dosing of the two reactants is essential. A feedforward−feedback control loop was conceived in order to maintain the reaction as closely as possible to the stoichiometric ratio, leading the path to full process automation. The feedback control loop relies on NIR transmission measurements performed in a flow cell where, in contrast to labor-intensive offline HPLC analytical methods, the whole reaction product can be scanned in real time without sample dilution. A robust PLS (projection to latent structures) model was developed with a satisfactory standard error of prediction, providing quantification of the ketone substrate in solutions with a high variability of the major solution componentthe alkoxide product. In addition, model performance supervision tools such as the spectral residuals or simple plots of pretreated spectra can assist in the identification of spectral outliers, which in this case could be related to Grignard reagent excess. If the sampling time of the NIR instrument is short enough, manipulating the inputs to the reactor may be used to obtain information about its dynamic behavior. This information is very useful for process control design, assessment of analytical tools and definition of sampling times. In this work, a systematic procedure for chemometric model building is followed, after which a discussion is made on some of the potential applications that can be found when exploiting the fast and rich information provided by NIR spectroscopy.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Monitoring and Control of a Continuous Grignard Reaction for the Synthesis of an Active Pharmaceutical Ingredient Intermediate Using Inline NIR spectroscopy

Padrell

Nielsen

Pedersen

et al. 2012

Org. Process Res. Dev.

View full text Add to dashboard Cite

show abstract

“…The analyzer was calibrated using the synchronized liquid GC data (estimated octane numbers and individual components) and the NIR spectral data from 5000 to 9500 cm –1 . A standard multivariate approach was followed for the quantitative NIR analysis where the “full spectrum” is correlated with the desired product properties as opposed to using specific peaks or spectral features . The analyzer allows for automated quantitative analyses through partial least-squares (PLS) models created using the GRAMS IQ software.…”

Section: Experimental Sectionmentioning

confidence: 99%

“…Although this methodology has been shown to be quite effective, it is still dependent on a fairly lengthy GC method and, in our case, not available as an on-line method. It has been proposed earlier that on-line near-infrared (NIR) spectrometry could be a suitable process analytical tool to monitor reformate properties . In fact, one of the very first applications of on-line NIR spectrometry in fuels refining was that of estimating gasoline octane number and other fuel properties .…”

Section: Introductionmentioning

confidence: 99%

Catalytic Naphtha Reforming: A Novel Control System for the Bench-Scale Evaluation of Commercial Continuous Catalytic Regeneration Catalysts

Caricato

Hoffeldt

Kotze

et al. 2017

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

An automated control system was developed for the bench-scale evaluation of continuous catalytic regeneration (CCR) naphtha reforming catalysts. Deactivation of these catalysts is too rapid for fixed bed operation, and regenerating the catalyst continually is not feasible on bench scale. To emulate the commercial process, a solution was required which would allow catalyst evaluation at a constant research octane number (iso-RON). Because changes are too fast for manual adjustment (especially when using Fischer–Tropsch naphtha), automated adjustment of process conditions was required. This was achieved through the use of simple matrix algebra, semiautomated gas chromatography and on-line near-infrared (NIR) analyses. Commercial catalysts with very small activity and reformate yield differences, could be compared and their RON versus yield correlations determined. Product samples large enough for engine research octane number (RON) analyses could also be collected at steady state. Through the use of multidisciplinary analytical and advanced process control techniques, substantial improvement of bench-scale piloting methodology in naphtha reforming was obtained.

show abstract

“…The proposed design is particularly advantageous for continuous monitoring of fluid flow parameters, crucial for several applications in life sciences, medicine, environmental, and process analysis [66,67], as listed in the following. Optical and non-optical sensors operated in parallel would allow for measuring parameters, such as turbidity, color, the content of certain particles, the pH value or the oxygen content.…”

Section: Optofluidic Platformsmentioning

confidence: 99%

Modular Platforms for Optofluidic Systems

Brammer

Mappes

2014

Optofluidics, Microfluidics and Nanofluidics

View full text Add to dashboard Cite

Optofluidics is increasingly gaining impact in a number of different fields of research, namely biology and medicine, environmental monitoring and green energy. However, the market for optofluidic products is still in the early development phase. In this manuscript, we discuss modular platforms as a potential concept to facilitate the transfer of optofluidic sensing systems to an industrial implementation. We present microfluidic and optical networks as a basis for the interconnection of optofluidic sensor modules. Finally, we show the potential for entire optofluidic networks.

show abstract

Future Trends in Process Analytical Chemistry

Cited by 14 publications

References 32 publications

Monitoring and Control of a Continuous Grignard Reaction for the Synthesis of an Active Pharmaceutical Ingredient Intermediate Using Inline NIR spectroscopy

Monitoring and Control of a Continuous Grignard Reaction for the Synthesis of an Active Pharmaceutical Ingredient Intermediate Using Inline NIR spectroscopy

Catalytic Naphtha Reforming: A Novel Control System for the Bench-Scale Evaluation of Commercial Continuous Catalytic Regeneration Catalysts

Modular Platforms for Optofluidic Systems

Contact Info

Product

Resources

About