Study On The Preparation Of Nano-Ceria By Detonation Method With Special Emulsion Explosives And Its Performance

In this paper, the special emulsion explosives used to synthesize nano-ceria by detonation method were prepared, in which Ce(NO3)3·6H2O was cerium source. Nano-ceria was synthesized by initiating the emulsion explosives in an explosion vessel. Several aspects, including size control method of nano-ceria particles during the synthesis process, post-processing method of target product and the performance of nano-ceria, were focused on.The main contents of this paper are as follows:(1) The special emulsion explosives used to synthesize nano-ceria by detonation method were developed by establishing and solving the mathematic model for the formulation design of special emulsion explosives. The optimized parameters to prepare special emulsion explosives were obtained by considering the heating temperature of aqueous phase and oil phase, rotating speed of emulsion machine, as well as the sensitizing temperature. The rationalities of the designed special emulsion explosives with10%,20%,30%and40%Ce(NO3)3in them respectively were verified by combining the experimental results and theoretical calculation results.(2) The size control method of nano-ceria particles synthesized by detonation method with special emulsion explosives was studied systematically. The effects exerted by several factors, including the content of Ce(NO3)3in the explosives, inert additives, rotating speed of emulsion machine and reactive rate of detonation, on the size of nano-ceria particles and its uniformity were studied. The method to synthesize nano-ceria with uniform size was obtained. It was found that there was certain corresponding relation between the size and uniformity of aqueous phase droplets in emulsion matrix and those of nano-ceria particles.(3) On account of there were some impurities, e.g. metallic oxides, in detonation products which were collected during the detonation synthesis process of nano-ceria, an orthogonal experiment was designed considering five main factors, such as quantities of HNO3, quantities of HCl, quantities of distilled water, purifying time and purifying temperature. In the experiment, the effects of different reaction conditions on the purity of nano-ceria powder were studied and the optimized combination of factors and levels was obtained.(4) The effects exerted by different temperatures in heat treatment process on the lattice structure of nano-ceria grain and the morphology of nano-ceria particles were studied by means of X-Ray Diffraction (XRD) and Transmission Electron Microscope (TEM). The optimized temperature of heat treatment was obtained. (5) In order to explore the application of nano-ceria synthesized by detonation method, the effects of nano-ceria which acted as the additive on the thermal decomposion of Ammonium Perchlorate (AP) and Hexogen (RDX) were studied with Differential Scanning Calorimetry (DSC). Thermal kinetic analysis was introduced to calculate the apparent activation energy and critical explosion temperature of those energetic materials in the conditions which were with or without the presence of nano-ceria. The results indicated that nano-ceria could promote the thermal decomposion of those energetic materials.(6) The ultraviolet absorption performance of nano-ceria synthesized by detonation method with special emlusion explosives was studied with Ultraviolet Spectrophotometer. The results presented that nano-ceria synthesized by detonation method with special emlusion explosives had excellent performance on absorbing ultraviolet.