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Physical and Chemical Changes of Hydrogen Peroxide Under High Pressures

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Physical and Chemical Changes of Hydrogen Peroxide Under High Pressures Physical and chemical changes of hydrogen peroxide under high pressures Jing-Yin Chen and Choong-Shik Yoo (PI) Washington State University, Pullman, Washington 99164 ) -1 1575 9.5% 19.6% Motivations and Objectives Phase Transitions in H2O2 Behaviors 1550 of Binary Mixtures: H2O + H2O2 1525 RamanShifts (cm Ref: H. Cynn, S.A. Sheffield & C.S. Yoo, J Chem. Phys. 110, 1999, 6836-6843 C (wt %) Raman Spectral Evidence H2O2 Structural Evidence downloading 10 30 50 70 90 5 (b) H O -I H O -II H O -I Transition 2 2 2 2 2 2 H O -II 0 10 1040 Zone 2 2 tetragonal orthorhombic 19.6% 4 GPa 3.3 c 8 c ) 9.5% -1 1000 44 b melting 6 GPa 2.6 40 3 (c) (a) 960 35 32 4 a Lattice Parameters (A) Parameters Lattice a 2 25 (GPa) P decomposition * 920 16 H O -I 2 2 Raman Shift (cmRaman Shift 16 5 1 O in H-type 2 3 GPa V=8.6% water cage 880 O in D-type O2 hydrate clathrates 2 800 1000 1200 water cage 0 1 2 /mol) 14 O 0 10 20 30 40 50 3 0 20 40 60 80 100 2 (9.5% H O ) Pressure (GPa) C (mole %) 2 2 H O -II H2O2 H O is a strong oxidizer and even explosive, and is often used as IED (cmV 2 2 2 2 12 4 D-type Ref: J.Y. Chen and C.S. Yoo, J. Chem. Phys. 132, 214501 (2010) Phase transition occurs at lower pressure3 for Intensity (a.u.) H-type Stability and behavior of H2O2 and water mixtures are not known 0 5 10 15 20 25 30 35 40 diluted samples. O Shock-induced detonation of concentrated H2O2 has been observed at ~13-15 GPa 2 Pressure (GPa) (19.6% H O ) Oxygen clathrates are observed at low 2 2 Behaviors of highly concentrated H2O2 are not known under static high pressures concentrated mixtures 5 6 Phase transition at 13 GPa from H2O2-I to -II, based on Raman and x-ray data 1520 1540 1560 1580 Raman Shifts (cm-1) Mitigating chemical and shock threats of H O requires understanding It accompanies a volume collapse of ~ 8.6% 2 2 The presence of water stabilizes the H2O2 mixtures by Pure H O is chemically stable to pressures 18 GPa of the stability of H2O2-H2O mixtures at relevant thermal conditions 2 2 forming stronger hydrogen bonds Experimental Approach Chemical Decomposition of Compressed H2O2 Detonation in Shocked H2O2 Under Static High Pressure at WSU O from H O decomposition EOS comparison of H O , H O, O Homogenous detonation model 2 2 2 2 2 2 2 1700 20 H O -I H O -II 2 2 2 2 us(O2) H +O Pure O 18 2 2 2 ) -1 Decomposition 16 H O + ½ O starts H O -I 2 2 2 2 14 /mol) 1600 3 44 12 V (cmV H O -II 25 2 2 10 O Raman Shift (cm -O 2 2 19 Diamond anvil cell Confocal micro-Raman Synchrotron x-rays 3 GPa 8 H O 2 Pressurizing Phase mapping Characterization 1500 1600 1700 1500 6 0 10 20 30 40 50 0 10 20 30 40 50 Pressure (GPa) Under Dynamic High Pressure at LANL P (GPa) H2O2 decomposition across the melting at 2.5 GPa H2O2 O 2 98 % H2O2 detonates at 6.7 Km/s (13-15 GPa). It seems to follow homogenous detonation model based on the spatially resolved wave profile measurement The work has been done in collaboration with D. Dattelbaum and S. H2O Sheffield In LANL Is shock-induced detonation different from the static H2O2 target with stress gauge Loading H2O2 2-Stage gas gun Decomposition of H2O2 is driven by densification and melting pressure-induced decomposition ? The work has been supported by the US DHS under the grant number 2008-ST-061-ED0001. For details, please contact [email protected] or [email protected].
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