Final Thesis

Analysis of dissociation for mono- and di-protonic carboxylic acids via in-line Raman spectroscopy

Key Info

Basic Information

Process Systems Engineering
Bachelorthesis / Projectthesis
Focus/Key Topic:
experimental / simulativ


The use of renewable resources provides manifold opportunities for the development of new sustainable processes, e.g. for the conversion of woody biomass into platform chemicals [1]. Mono- and di-protonic carboxylic acids belong to the group of top value-added chemicals from biomass according to a study of the U.S. Department of Energy [2]. For innovative process design, a detailed understanding of the behavior of such carboxylic acids at high pressures and temperatures in aquatic and/or organic media is crucial. Under such conditions, conventional measurement techniques e.g. for pH-values of the different acidic species are not applicable anymore. Here, in-line Raman spectroscopy as a tool for non-invasive, time-resolved and robust analysis under harsh environmental conditions can be applied [3, 4]. In this work, a selection of six mono- and di-protonic carboxylic acids in aquatic solution will be investigated by in-line Raman spectroscopy.

In a first step, a thorough research for relevant literature has to be performed. In a second step, aquatic samples of the selected acids at different pH-values have to be prepared. Subsequently, these samples need to be measured by in-line Raman spectroscopy. In a fourth step, the results from Raman spectroscopy provide the basis for the generation of calibration models for the acidic species employing the software tool Peaxact. Finally all results have to be documented and evaluated.

The work can be prepared in English or German. There are no special prerequisites. Experience with laboratory work can be helpful, but is not required, though. Careful, independent and self-reliant work is expected. Motivation, interest and fun for experimental work is never wrong. If you are interested, feel free to contact us with a short CV and record of grades to arrange a meeting.

[1] Mika, László T., Edit Cséfalvay, and Áron Németh. "Catalytic Conversion of Carbohydrates to Initial Platform Chemicals: Chemistry and Sustainability." Chemical reviews (2017)
[2] Werpy, Todd, et al. Top value added chemicals from biomass. Volume 1-Results of screening for potential candidates from sugars and synthesis gas. No. DOE/GO-102004-1992. Department of Energy Washington DC, 2004
[3] Eifert, T., and M. A. Liauw. "Process analytical technology (PAT) applied to biomass valorisation: a kinetic study on the multiphase dehydration of xylose to furfural." Reaction Chemistry & Engineering 1.5 (2016): 521-532
[4] Rudolph, Wolfram W. "Raman-spectroscopic measurements of the first dissociation constant of aqueous phosphoric acid solution from 5 to 301 C." Journal of solution chemistry 41.4 (2012): 630-645