In
chemistry,
heterogeneous catalysis refers to the form of
catalysis where the phase of the
catalyst differs from that of the
reactants. Phase here refers not only to
solid,
liquid, vs
gas, but also immiscible liquids, e.g.
oil and
water. The great majority of practical heterogeneous catalysts are solids and the great majority of reactants are gases or liquids. Heterogeneous catalysis is of paramount importance in many areas of the chemical and energy industries. Heterogeneous catalysis has attracted
Nobel prizes for
Fritz Haber and
Carl Bosch in 1918,
Irving Langmuir in 1932, and
Gerhard Ertl in 2007.