The invention involves palladium and ceria-based catalysts for the after treatment of exhaust gases from motor vehicles. The proposed materials are prepared by a new dry procedure which eliminates the need of solvents and is characterized by a higher activity and sustainability compared to the traditional wet methods.
Patent Status
PENDING
Priority Number
IT102017000070360; PCT/IB2018/054583
Priority Date
23/06/2017
License
INTERNATIONAL
Market
The invention is relevant for the market of thermal catalysts and emission-reducing systems.
Problem
The growing attention towards the containment of greenhouse gas emissions in various fields has stimulated the search for new solutions in order to minimize the impact of the energy production through combustion of gas and fossil fuels. Methane is the most commonly used gaseous fuel. Among fossil fuels, it offers a cleaner alternative as its combustion leads to reduced harmful emissions. If used in the form of bio-methane it could increasingly meet sustainability requirements. The removal of unburned methane from exhausts, however, still represents a major challenge. In fact, methane is a greenhouse gas whose global warming potential is 25 times higher than that of CO2. It is therefore very important to minimize its emissions. Currently, the abatement of unburned CH4 is achieved by catalysts. However, the efficiency of catalytic abatement is not optimal.
In the field of catalytic methane abatement from natural gas-powered vehicles, the state of the art is represented by palladium-based catalysts supported on different types of oxides. Cerium oxide as a support or promoter considerably improves the catalytic activity. Despite the progress in the sector, an improvement in the general catalytic activity of these materials is desirable, especially with regard to their activation at low temperatures.
Current Technology Limits
At present, catalyst preparation methodologies prefer the impregnation of a solution of a precursor salt of palladium on the support, followed by drying and calcination. In general, the techniques require that one or more steps of the procedure take place in solution. Attempts to apply solvent-free “dry” methodologies have not yielded satisfactory results. The “dry” preparation methodology revealed in this invention allows to prepare with a simple passage of a few minutes a Pd/ CeO2 catalyst that has an activation temperature for the oxidation of methane lower than that of the materials currently in use.
With this invention is possible on one hand to reduce the costs and production time of the catalyst, and on the other hand to obtain a more active material than traditional catalysts. The Pd/CeO2 catalyst thus obtained, in the form of powder, has macroscopic characteristics in all respects similar to those of the materials already in use, excluding the need for special modifications for its use.
Killer Application
Many industrial processes involve the use of methane, in addition to thermal engines which are fueled by methane, such as drying systems of materials and post-painting drying systems. The abatement of unburnt methane and other pollutants is therefore of great importance for the industrial sector.
The catalysts developed by the researchers undoubtedly offer a useful technology for controlling its emissions from industrial and mobile sources.
Our Technology and Solution
The invention allows catalysts to be prepared by dry grinding without the use of solvents. This reduces the environmental impact of the process both from the point of view of storage and disposal of solvents and from the energy point of view, as many of the related heat treatments are eliminated. The grinding procedure is low energy consuming and can be applied to a number of materials, depending on the needs, in addition to palladium and cerium oxide as starting materials.
Thanks to the developed methodology, materials with a shell structure are obtained, that are particularly active and stable in the activation of methane and in the post-combustion of other pollutants.
The scale-up of the technology has involved the production of quantities of 0.1-1kg of material and the development of more complete formulations including in the preparation of the material other metals and/or doping elements (e.g. Rh, Zr or Al). This allows you to easily get to a pre-industrial prototype.
Advantages
The main advantages of these catalysts are:
Roadmap
Collaboration with companies producing catalytic converters or emission control systems is desirable. The technology currently has a TRL of 5(6); collaboration with companies that produce emission control systems (such as catalytic converters for thermal engines and/ or abatement of emissions from thermal engines) can easily lead to product placing on the market.
TRL
Team
