Reductions belong to one of the oldest types of chemical processes carried out on technical scale. In organic synthesis, complex metal hydrides, e.g. lithium aluminum hydride, are mainly used for the selective reduction of particular functional groups.
The following table gives an overview of the reducing properties of commercially available complex metal hydrides.
Reducing Properties of Hydrides
Reductions are mainly applied in the following industries:
- Flavors and fragrances.
The binary metal hydrides, i.e. sodium and lithium hydride, are used as strong bases in organic synthesis.
Another application of complex metal hydrides is the manufacture of high-purity organosilanes which are synthesized by a reduction of the corresponding chlorosilanes, for example, with lithium aluminum hydride. These organosilanes are used as raw-material gases for the chemical vapor deposition in the production of semiconductor devices.
Albemarle's various grades of calcium hydride desiccate gases and liquids by means of an irreversible reaction with water. Here, 7 kilograms of CaH2 have the capacity to remove 6 kilograms of water.
Calcium hydride serves as a convenient source of clean albeit wet hydrogen, by reacting with water in simple, low-cost, lightweight generators. One kg of calcium hydride yields 1.05 m3 of hydrogen at standard temperature and pressure. During the reaction with water, the quantity of hydrogen contained by calcium hydride will increase to nearly twice its amount (including the hydrogen coming from water). This property is most useful in energy storage applications.