Preparation and characterization of mechanically durable, catalytic coatings for 3D-printed flow guiding elements for the use in the direct synthesis of hydrogen peroxide
Bachelor's / Master's Thesis / Student Assistant
Background and Motivation
Hydrogen peroxide (H2O2) is an environmentally friendly oxidizing agent with promising future potential: It is estimated that the current annual production of three megatons will continue to rise to more than five megatons within the next five years. The standard process for industrial H2O2 production is the anthraquinone process. However, due to the many process steps and the limited reusability of organic anthraquinone, this process does not allow a decentralized H2O2 production.
The direct synthesis of hydrogen peroxide on the other hand is an attractive synthesis route in which both molecular hydrogen and oxygen are contacted with a heterogeneous catalyst in a single reaction step. In recent years, intensive research has been conducted on the understanding of the reaction mechanism as well as on new reactor concepts in order to achieve a knowledge-based increase in intrinsic and reactor selectivity, which currently stands in the way of the industrial implementation of this method. The reason for this is that in addition to hydrogen peroxide, water is produced thermodynamically favoured as a by-product in various subsequent and parallel reactions.
At IMVT a novel membrane microreactor is used to overcome these reaction engineering challenges. A polymer membrane allows a bubble-free dosing of the reactants H2 and O2 into the liquid reaction medium which continuously flows through the reaction channel. Due to the alternating dosage of the reactants, the hydrogen peroxide concentration is not limited by the saturation concentration of the gases, as the consumed substances are always „replenished“. At the same time, specially developed 3D-printed channel inserts, so-called flow guiding elements, enable an intensified contact of the gases with the reaction medium. At the same time, these structures serve as carriers for the required catalyst.
Figure 1: Scheme of a Fluid Guiding Element with catalytically coated surfaces , adapted from  (left), 3D-printed Fluid Guiding Element  (right)
Topic and Tasks
Within the scope of a thesis (bachelor´s or master´s thesis), a coating method is now to be developed based on preliminary investigations. The coated structures are then to be characterized and tested.
The scope (bachelor's or master's thesis) and the focus of the thesis can be defined by individual consultation. The project is addressed at students of the faculties of chemistry or chemical engineering.
- Determination and evaluation of suitable coating materials and processes on the basis of a literature study and the results of previous investigations
- Production of coatings
- Characterization of the coatings: Analysis of the coating by SEM, chemisorption, physisorption and the thickness of the coating
- Students of chemical engineering / process engineering / chemistry
- Presentation of the results of the work within an institute seminar
- Language: English or German
Start: by arrangement
Examiner: Prof. Dr.-Ing. Roland Dittmeyer
Supervisor: Laura Trinkies (laura.trinkies∂kit.edu)
 Laura L. Trinkies, Benedikt J. Deschner, Edgar Hansjosten, Manfred Kraut, Roland Dittmeyer (2020). 4th Indo-German Workshop on Advances in Materials, Reaction & Separation Processes: Book of Abstracts. Berlin, 2020. Max Planck Institute for Dynamics of Complex Technical Systems; Indian Institute of Technology Madras, p. 90.
 E. Hansjosten, A. Wenka, A. Hensel, W. Benzinger, M. Klumpp, R. Dittmeyer (2018). Chemical Engineering and Processing – Process Intensification 130, 119 – 126.