Farbwerke Hoechst

Farbwerke Hoechst AG and Hbls AG have cooperated in the development of industrial-scale plasma units up to 10,000 kW (7). Yields of acetylene of 40—50 wt % with naphtha feedstock, and about 27 wt % with cmde oil feedstock, have been obtained. Acetylene concentration in the cracked gas is in the 10—15 vol % range. 

Hoechst WHP Process. The Hoechst WLP process uses an electric arc-heated hydrogen plasma at 3500—4000 K it was developed to industrial scale by Farbwerke Hoechst AG (8). Naphtha, or other Hquid hydrocarbon, is injected axially into the hot plasma and 60% of the feedstock is converted to acetylene, ethylene, hydrogen, soot, and other by-products in a residence time of 2—3 milliseconds Additional ethylene may be produced by a secondary injection of naphtha (Table 7, Case A), or by means of radial injection of the naphtha feed (Case B). The oil quenching also removes soot. 

Hoechst HTP Process. The two-stage HTP (high temperature pyrolysis) process was operated by Farbwerke Hoechst ia Germany. The cracking stock for the HTP process can be any suitable hydrocarbon. With hydrocarbons higher than methane, the ratio of acetylene to ethylene can be varied over a range of 70 30 to 30 70. Total acetylene and ethylene yields, as wt % of the feed, are noted ia Table 11. 

The first commercially available acetal resin was marketed by Du Pont in 1959 under the trade name Delrin after the equivalent of ten million pounds had been spent in research or polymers of formaldehyde. The Du Pont monopoly was unusually short lived as Celcon, as acetal copolymer produced by the Celanese Corporation, became available in small quantities in 1960. This material became commercially available in 1962 and later in the same year Farbwerke Hoechst combined with Celanese to produce similar products in Germany (Hostaform). In 1963 Celanese also combined with the Dainippon Celluloid Company of Osaka, Japan and Imperial Chemical Industries to produce acetal copolymers in Japan and Britain respectively under the trade names Duracon and Alkon (later changed to Kematal). In the early 1970s Ultraform GmbH (a joint venture of BASF and Degussa) introduced a copolymer under the name Ultraform and the Japanese company Asahi Chemical a homopolymer under the name Tenal. 

Scherer, 0. and Kuhn, H. U.S. Patent 2,959,624 November 8, 1960 assigned to Farbwerke Hoechst AG vormals Meister Lucius Bruning, Germany McGinty, R.L. U.S. Patent 3,082,263 March 19,1963 assigned to Imperial Chemical Industries Limited, England... 

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