(Szentgál, September 30th 1867- Budapest, September 7th 1941)
In September 1887 he started his studies in the section of chemistry at József Technical University and got a diploma of chemical engineering here in 1892, and was an assistant lecturer for two years at the Faculty of Chemical Technology. A product of this period is the book entitled Alcohol tables of 735 pages
Laying down his position as assistant lecturer he started to work as a chemist in the chemical laboratory of MÁV (Hungarian State Railways). First he developed a procedure for the determination of the hardness of water; since then the so-called Wartha-Pfeifer process has been a part of the history of water chemistry. In his publications he dealt with the problems of the chemical purification of boiler waters and the reduction of corrosion and crustification for four years. He was engaged in heating technique, studied the suitability of home coals and proved the superfluousness of a considerable percentage of the import. His book entitled Survey of Boiler Furnace Constructions" was published in 1898.
In 1900, after successful trial lecture he was appointed private professor at József Technical University. As a private professor he also undertook the edition of two journals.
Pfeifer opened a technical bureau in 1903. At that time he was engaged in problems of gas generators and assembled a gas analysing apparatus for them, he patented a process relating to the production of tar-free generator gas from brown coal. With Wartha he took part in the development of the gas factories of Budapest and he studied composition of natural gas in Hungary. He made a detailed proposition regarding the exploitation of natural gas. He was successfully engaged in the halogenation of carbon hydrides.
In 1907, on the recommendation of Wartha, Pfeifer was honoured with the title of assistant professor. He got the nomination of full professor at the Department of Chemical Technology and was for seven years one of the most successful professors at the Technical University
Later he was adviser for Gaswerk Baumberg in Hamburg, but he soon accepted the invitation of Lipót Aschner to be the head of the research and development laboratory to be established in United Incandescent-Lamp and Electrical Co. Ltd.
Pfeifer played a determining role in these years in the Hungarian Chemical Society where he was elected acting president in 1929.