It is with deep sadness that we bid farewell to our esteemed colleague Albert Hackl, who passed away on June 17, 2025.

He was born on November 2, 1928, in Vienna, was widowed at the time of his death, and had one son. He studied chemical engineering with a focus on fuel technology and combustion/gas technology at the Vienna University of Technology, where he received his doctorate in 1960. In 1969, he became an assistant professor of basic process engineering at the Vienna University of Technology, and in 1973 he was appointed professor in this field. From 1969 to 1971, he studied law at the University of Vienna. In 1987, Albert Hackl was awarded an honorary doctorate in engineering by the Technical University of Dresden. After more than a decade of research and teaching in the field of thermal and mechanical process engineering, environmental protection and the relevant technologies came to the fore due to forest dieback in the 1970s and the first oil crisis in 1973. In line with his fuel/gas-oriented studies, he began to focus his research and teaching on environmental protection issues and technologies, and since 1985 also on greenhouse gases.

Based on his specific studies, annual contacts with Japanese scientists and engineers, and informational visits to the US and Japan, he introduced flue gas desulfurization and later SCR technology to reduce NOx emissions for use in Austrian thermal power plants. Most recently, he used it to destroy dioxins and furans in waste incineration plants.

Albert Hackl held many positions related to science. He was chairman of the CO₂ Commission advising the Austrian federal government, the scientific committee for legal emission standards for SO₂ and NOx, the scientific advisory board for waste management at the BMfUJF, the Academy for Energy and Environment of Lower Austria, the Interdisciplinary Commission for the Environment at the Vienna University of Technology, and the “Clean Air” working group of the Austrian Institute for Standardization. In addition, he was vice-chairman of the Ludwig Boltzmann Institute for Mineral Oils. He also served as the Austrian delegate in the ECE's “Exhaust Gas Reduction Techniques” working group in Geneva and as spokesperson for the Austrian delegation in Japan to demonstrate the state of the art in SCR techniques. He was also a member of the board of the European Research Center for Clean Air in Strasbourg/Karlsruhe, the Commission for Climate and Air Quality of the Austrian Academy of Sciences, and the Scientific Advisory Board for Environmental Problems of the Province of Vienna. He worked as an official senior expert in combustion technology and flue gas cleaning for Austrian waste incineration plants and thermal power stations, and as an officially appointed senior expert advising authorities in Paris and Zagreb on the introduction of flue gas cleaning systems in industrial plants.

His comprehensive and highly successful scientific work has been recognized with numerous prestigious awards, including the Theodor Körner Prize (1970) and the Grand Medal of Honor for Services to the Province of Lower Austria (1990). In 1991, he became an honorary member of the Academy for Environment and Energy of the Province of Lower Austria. In 1996, he was awarded the Gold Medal for Services to the Province of Vienna and the Gold Medal of the Filtration Society of England. In 1997, he was awarded the Austrian Cross of Honor for Science and Art, 1st Class, and in 2010, he received the Lower Austria Merit Award for Scientific Research in Museums.

Albert Hackl's highly successful scientific work is also represented by over 200 publications on thermal and mechanical process engineering, flue gas cleaning, and greenhouse gas issues in the relevant German, English, French, and Czech technical literature. He was the editor of two series of technical books and holder of four patents.

Privately, as a descendant of the textile manufacturers of the “k.k. priv. Modewarenfabrik Hackl & Söhne” (Imperial and Royal Private Fashion Factory Hackl & Sons), he also had close ties to the town of Weitra in Lower Austria. He was very committed to preserving two vacant factory buildings of the abandoned textile factory and setting up a museum there. In 1990, the “Alte Textilfabrik” museum was finally opened in Brühl near Weitra. It was very important to him to bring the working and living environment of employers and employees in the 19th century to life in this museum. Albert Hackl mobilized financiers, partners, and expertise, and promoted networking with other institutions to make this museum with its many special exhibitions a reality. In April 2024, the “Hackl Promenade” was opened in Weitra in his honor.

We bid farewell to Albert Hackl with gratitude and appreciation. He leaves behind a void, but also a legacy that will endure.

On behalf of all colleagues at the Institute of Process Engineering, Environmental Technology, and Technical Biosciences,

Robert Mach, head of institute