All industrial processes Inevitably lead to the creation of sub-products which, unless another use of fund for them, are regarded as waste. They are a source of land, water and air pollution. Often, products regarded as waste contain precious materials because they are rate or difficult to extract. This is why now increasingly attempts are made to minimise the amount of waste, to recycle or re-use sub-products as secondary raw materials. The aim of the present research project is to study processes, systems and technologies capable of recovering precious metals from spent catalysts. Catalysts in fact contain metals with a high economic value (such as Molybdenum and Vanadium, as well as others) which, if recovered, could allow rational re-utilisation of the raw materials in full compliance with the approach encouraged by the European Community. The process idea The central idea is to recover the metals present in spent catalysts using a chemical process which consists in: 0 a first phase where the catalyst is dissolved to obtain a solution containing the metals in liquid state; 0 a second phase where the metals react in order to obtain a precipitate in salt form Obviously the process is already at the level of laboratory tests and additional, substantial research activity is needed to create a pilot system that exploits the process in order to recover Vanadium and Molybdenum from all spent catalysts containing them. It is also important to discover methods of recovering the metals present in the catalysts most frequently used in industry throughout Europe. More specifically, it is necessary to: test the possibility of recovering other metals from catalysts, quantify the costs and economic benefits of industrialising the process; in particular, we need to find out in what conditions recovery is economically competitive compared with regenerating the catalyst, optimise the process in order to minimise costs and maximise production, study the technologies necessary to implement the process on an industrial scale, realise a pilot plant that exploits the method developed.