BMA process
Encyclopedia
The BMA process or Degussa process is a chemical process developed by the German chemical company Degussa for the production of hydrogen cyanide from methane
and ammonia
in presence of a platinum
catalyst
. Hydrogen cyanide is used in the chemical industry for the production of intermediate chemicals like acrylonitrile
, methyl methacrylate
, and adiponitrile
.
The reaction equation is analog to the steam methane reforming (SMR)
reaction of methane and water:
The reaction is extremely endothermic
. The reactants react in a Platinum-covered pipe at temperatures around 1400°C. The reaction mixture contains around 23 Vol.-% HCN and 72 Vol.-% H2 as well as minor quantities of ammonia, nitrogen, and unreacted methane.
The gaseous mixture is introduced in a scrubber
and treated with an ammonia solution in order to separate the acidic HCN from the other gaseous components: H2, CH4, and N2. In a second step the HCN is released by acidification of the solution, followed by a final distillation of the hydrogen cyanide. Because of the highly endothermic reaction, the BMA process is of lower importance for the production of HCN compared to the Andrussow oxidation
.
Methane
Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...
and ammonia
Ammonia
Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...
in presence of a platinum
Platinum
Platinum is a chemical element with the chemical symbol Pt and an atomic number of 78. Its name is derived from the Spanish term platina del Pinto, which is literally translated into "little silver of the Pinto River." It is a dense, malleable, ductile, precious, gray-white transition metal...
catalyst
Catalysis
Catalysis is the change in rate of a chemical reaction due to the participation of a substance called a catalyst. Unlike other reagents that participate in the chemical reaction, a catalyst is not consumed by the reaction itself. A catalyst may participate in multiple chemical transformations....
. Hydrogen cyanide is used in the chemical industry for the production of intermediate chemicals like acrylonitrile
Acrylonitrile
Acrylonitrile is the chemical compound with the formula C3H3N. This pungent-smelling colorless liquid often appears yellow due to impurities. It is an important monomer for the manufacture of useful plastics. In terms of its molecular structure, it consists of a vinyl group linked to a nitrile...
, methyl methacrylate
Methyl methacrylate
Methyl methacrylate is an organic compound with the formula CH2=CCOOCH3. This colourless liquid, the methyl ester of methacrylic acid is a monomer produced on a large scale for the production of poly .-Production:...
, and adiponitrile
Adiponitrile
Adiponitrile is the organic compound with the formula 42. This dinitrile, a viscous, colourless liquid, is an important precursor to the polymer nylon 66. In 2005, about one billion kilograms were produced annually.-Early routes:...
.
The reaction equation is analog to the steam methane reforming (SMR)
Steam reforming
Fossil fuel reforming is a method of producing hydrogen or other useful products from fossil fuels such as natural gas. This is achieved in a processing device called a reformer which reacts steam at high temperature with the fossil fuel. The steam methane reformer is widely used in industry to...
reaction of methane and water:
- CH4 + NH3 → HCN + 3 H2, ΔHR = 251 kJ / mol
The reaction is extremely endothermic
Endothermic
In thermodynamics, the word endothermic describes a process or reaction in which the system absorbs energy from the surroundings in the form of heat. Its etymology stems from the prefix endo- and the Greek word thermasi,...
. The reactants react in a Platinum-covered pipe at temperatures around 1400°C. The reaction mixture contains around 23 Vol.-% HCN and 72 Vol.-% H2 as well as minor quantities of ammonia, nitrogen, and unreacted methane.
The gaseous mixture is introduced in a scrubber
Scrubber
Scrubber systems are a diverse group of air pollution control devices that can be used to remove some particulates and/or gases from industrial exhaust streams. Traditionally, the term "scrubber" has referred to pollution control devices that use liquid to wash unwanted pollutants from a gas stream...
and treated with an ammonia solution in order to separate the acidic HCN from the other gaseous components: H2, CH4, and N2. In a second step the HCN is released by acidification of the solution, followed by a final distillation of the hydrogen cyanide. Because of the highly endothermic reaction, the BMA process is of lower importance for the production of HCN compared to the Andrussow oxidation
Andrussow oxidation
The Andrussow process is an industrial process for the production of hydrogen cyanide from methane and ammonia in the presence of oxygen and a platinum catalyst....
.