Cleaning services company Ecolab said it will buy privately held Champion Technologies, a maker of oilfield specialty chemicals, for about $2.2 billion in cash and stock.

Ecolab, whose technologies, chemicals and services are used in water treatment, pollution control, energy conservation, oil production and refining, said Champion's technology and products were complementary to its services in the offshore and international energy markets.

Ecolab, based in St. Paul, Minnesota, will pay about $1.7 billion in cash and issue about 8 million shares to Champion, subject to certain adjustments at and after closing.

Houston-based Champion, which competes with companies such as Schlumberger NV, Halliburton and Baker Hughes, had sales of $1.2 billion last year, Ecolab said.