Decomposition of a cation exchange resin with hydrogen peroxide

Ion exchange resins are widely used in the field of nuclear industry. The present work aimed at the development of a method for complete decomposition of cation exchange resins with H₂O₂ in the presence of Fe³⁺ ion. The decomposition reaction proceeded at ambient temperature and decomposition time was greatly shortened with increasing concentration of Fe³⁺ ion rather than that of H₂O₂. The catalytic action of Fe³⁺ ion was suppressed with increase of HNO₃ concentration. As much as 4 g of the air-dried resin could be decomposed with 8 ml of 30% H₂O₂, and the use of about 60 ml of 30% H₂O₂ resulted in the complete decomposition of organic carbon to CO₂. Absence of any orgnaic carbon in the residual solution will simplify the final disposal.     

Laser-ionization mass-spectrometric studies on laser ablation of a nitrogen-rich polymer at 532 nm and 1064 nm

Laser-ionization Time-Of-Flight (TOF) mass-spectrometric studies have been carried out on the 532 nm and 1064 nm laser ablation products from a nitrogen-rich polymer. The polymer used had an elemental composition of C_6.0N_8.9H_3.4 and consisted of C=N, C-N, and N-H chemical bonds. The TOF mass spectra observed were composed of various peaks (150 amu) depending on the ablation laser wavelength. The primary peaks were assigned to C⁺, CN⁺, CHnN⁺ ₂ (n=1–3) and C₂H₂N⁺ ₃ for 532 nm ablation, and C⁺, C⁺ ₃, HCN⁺, HCCN⁺, CH₂NH⁺, HNCN⁺, H₃NCN⁺, and C₄H₄N⁺ ₇ for 1064 nm ablation. The flight velocity distributions with peak velocities ranging from 8.6×10³ cm/s to 3.8×10⁴ cm/s were measured for these products. The distinct velocity distributions observed between small and large products indicate the presence of two origins in the fragment ejection process from the polymer for both 532 nm and 1064 nm ablation. Furthermore, we suggest an importance of the translational energy of the fragments for the product generation in the laser plume.