Abstract: A production complex is used for producing nano-particles of metal from volatile moieties like metal carbonyls in a flow through reactor. The carbonyls are fed into the reactor through a first feeder, which is a moiety feeder. The moiety, a mixture of metal carbonyl and a bearer fluid, is entering the reactor in a vaporized state. Decomposition of carbonyls is carried out by controlled ambient temperature within the reactor, which is provided by means of a heated inert gas through a heating feed line of the production complex into a second feeder of the reactor, when the production complex is in an operational state. Gases like nitrogen are heated up in units of the production complex as heating feed. The gas supply unit in pre-operational state is used to provide inert gas for cleaning a carbonyl feed line in order to improve the quality of nano-particles of metal produced.