New fluidized bed reactor for coating of energetic materials

The process of altering and changing the properties of the energetic materials by coating has been studied extensively by several scientific groups. According to the desired application different coating techniques have been developed and applied to achieve satisfactory results. Among the already developed and used techniques are:
ALD (atomic layer deposition), CVD (chemical vapor deposition), FEM (fluid energy mill), crystallization, aerosol-spray pyrolysis, Ziegler-Natta reaction and others.
In TNO Defence, Security and Safety in The Netherlands, a facility for coating of energetic materials has been constructed. We propose a new plasma coating technique for energetic materials where a new type of Dielectric Barrier Discharge (DBD) is used with sufficiently improved production rates. Our facility aims to treat powders in the low micron range and at ambient temperature. The range of materials that can be treated is not restricted by their temperature sensitivity. Our facility is based on circulating solid-gas fluidized bed. The coating capacity is approximately 40g of energetic powder material per minute. This is possible because of the re-circulation nature of the fluidized bed. The precursors are introduced in the system in gas phase. The energy efficiency of the coating process is determined by the input plasma power, flow rate and molecular weight of the reaction gas and the treatment time.
The research field, in which the facility is primarily used, is the reduction of sensitivity of several MIC’s (metastable intermolecular composites) and possibilities for prolonged shelf-life. This paper describes the design of the new fluidized bed plasma reactor as well as the research program on reduction of energetic materials sensitivity and manufacturing of novel energetic materials.