When doing in the off-gas purification business you will pretty soon register that you do not act in an isolated box. You have to make yourself familiar with the interplay of your emission problem and the environment, and you have to apply a broad view of the subject.

We can hardly make a forecast on your first steps in this business, except that we want you to succeed.

Therefore, we want to offer engineers and graduate students the basic tools for discussing air pollution problems and for deducing strategies for process and equipment design in off-gas purification, covering the whole span from the basics to dedusting, absorption, adsorption and redox processes.

The didactic concept of the work is to attract students with a 'learning by doing' strategy. We discuss the problems, the solver strategies and the solvers. The problem solver proposals address a multitude of pollution control technologies.

The work is a compact off-gas purification guide for practitioners and students by presenting basics as well as numerous applications with many examples and problems with solutions.

__Univ.-Prof. Dipl.-Ing. Dr. Matthaeus Siebenhofer, born in 1955, decided to make chemical Engineering to his professional mission. After having finished PhD studies in 1983 he started his professional career in the engineering group of a refractory company with the focus on off-gas pollution control. His experience soon led to the appointment as lecturer at Leoben University of Mining and at Graz University of Technology and in 2005 as full professor at Graz University of Technology. During his academic career he had the opportunity to care for several thousand students, to share his experience with the students and to prepare them for later activities in research and industry. He always tried to suffice his ambitions in teaching to achieve one hundred message transfer efficiency. After retiring in 2020 he successfully convinced two former students to share authorship, when summarizing the experience in teaching off-gas purification.

__Dr. techn. Annika Grafschafter, born in 1986, grew up in Himmelberg, a small Carinthian village in Austria. After she graduated from an arts school, she decided to follow a new path and started her studies in process engineering at Graz University of Technology. During her education she gained professional experience in various companies. In 2016, she started her PhD studies in the field of extraction technologies and apparatus design at the Institute of Chemical Engineering and Environmental Technologies. Matthaeus Siebenhofer was her mentor who encouraged her with his vast experience. During her PhD studies, she was able to present her research work worldwide and gained several awards. Besides research, she gave lectures for mass transfer unit operations and was able to fascinate students for the practical aspect of this topic. She graduated in 2019 and started her professional career for an engineering service provider in process industry.

__Susanne Lux, born in 1981, has dedicated her professional career to chemical reaction engineering. After having finished PhD studies she started to teach together with her mentor M. Siebenhofer at Graz University of Technology. In 2021 she was awarded the venia docendi for chemical reaction engineering. Since then she has been responsible for the reaction engineering education of chemical and process engineering students at Graz University of Technology. In teaching, she covers all aspects of chemical reaction engineering, ranging from its fundamentals to applied tasks such as off-gas purification by chemical conversion. In research, she focuses on heterogeneous catalytic and multi-phase reactions to address current industrial and environmental challenges.