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Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid
Published on: November 15, 2017
Synthesis and characterization of spherical 2-diazo-4,6-dinitrophenol (DDNP)
Zong-Wei Yang1, Yu-Cun Liu, Deng-Cheng Liu
1Chemical Industry and Ecology Institute, North University of China, Taiyuan, Shanxi 030051, China.
Abstract:
Spherical 2-diazo-4,6-dinitrophenol (DDNP) with good flowability and controlled bulk density (0.65-0.95 g/cm(3)) has been prepared at factory scale by the modified method using 4-methylphenol as crystal control ingredient. Results showed that the yield of product was increased by 5-10%, and the waste water was significantly decreased due to circulation use of waste water compared with traditional method. Synthesized spherical DDNP was characterized by IR, laser granularity measurement, SEM, HPLC and XRD. IR spectrum confirmed the structural features of spherical DDNP. The particle analysis revealed that the modified method could offer spherical DDNP with average particle size of 350 microm and high purity (>98.52%). The XRD peaks of spherical DDNP have similar diffraction angles as those of traditional DDNP. The DSC profile of spherical DDNP showed the exothermic decomposition in the temperature range of 161.2-188.5 degrees C. The product can be pressed at over 40MPa without dead pressed phenomenon, and the minimum detonating charge of spherical DDNP was measured to be about 0.15g. Furthermore, impact sensitivity test suggested that spherical DDNP is less sensitive than traditional DDNP.
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