Degussa black process

Both processes are still used in industry for the production of carbon black. The channel black process, a process for making impingement blacks, has been used in the United States since the end of the 19th century. This process, which has now been abandoned because of economic and environmental considerations, used natural gas as raw material. A similar process for the production of impingement blacks, the Degussa gas black process, is still used today. 

In Germany, where natural gas was not available in sufficient amounts, the gas black process was developed in the 1930s. It is similar to the channel black process, but uses coal tar oils instead of natural gas. Yields and production rates are much higher with oil-based feedstock this process is still used to manufacture high-quality pigment blacks with properties comparable to those of channel blacks. The gas black process has been used by Degussa on an industrial scale since 1935. 

Figure 55. Degussa gas black process a) Oil evaporator b) Burner c) Cooling drum d) Bag filter e) Blower f) Rotary valve g) Conveying srew...

Thermal-oxidative decomposition Furnace black process Degussa gas black process Lamp black process Aromatic oils on coal tar basis or mineral oil, natural gas Coal tar distillates Aromatic oils on coal tar basis or mineral oil... 

The gas black process was developed in the 1930 s by Degussa AG as an alternative to the channel black process, because natural gas was not available in sufficient quantities in Germany. 

Degussa (now EVONIK), in Germany, developed the so-called gas black process in the 1930s. Initially coal tar was used, quite a common feedstock at that time, when carbochemistry was very important in a country that had limited access to petrol. Today, any kind of hydrocarbon feedstock may be used in the process. As shown in Figure 4.3, a carrying gas is flown over preheated oil, then the oil-rich gas feeds a burner. Smoke is in part captured on the wall of water-cooled rotating cylinders and removed with scrapers, and in part recovered through filtration. Very fine elementary... 

The product obtained from the vapor process is frequently termed fumed silica because it looks like smoke or fumes. This process was developed by applying carbon black production technology and equipment to silica tetrachloride in an invention by Degussa AG. Fumed silica manufactured is presently based on Degussa s license, which was sold to only a few other corporations. Metallic silicon and gaseous dry HCl are reacted to form silica tetrachloride, which is mixed with hydrogen and air and fed into the burner tube of the reactor where the following reactions occur ... 

The Degussa process for manufacturing gas black was developed in 1935 and is described by Buxbaum (1998). Oil vapour is carried in hydrogen, methane or coke-oven gas and combusted. Very fine particle sizes can be generated with the addition of air. 

Thermo-oxidative decomposition Thermal decomposition Furnace black Gas black (Degussa process) Lamp black Thermal black Acetylene black Aromatic oils from coal tar or petrol distillates, natural gas Coal tar distillates, natural gas Aromatic oils from coal tar or petrol distillates Natural gas (or oils) Acetylene... 

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