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The development of heterogeneous Fenton catalysts with good performance and stability is a challenge in the field of wastewater treatment. In this work, MgAlFe hydrotalcite-like compounds (MgAlFe-HTLcs) were prepared by solid phase reaction at room temperature and modified via a hydrothermal process. The experimental results showed that MgAlFe-HTLcs had a good layered structure with the same proportion of iron and aluminium, 18 h of crystallisation time and 110°C of crystallisation temperature and the lamellar structure was more uniform by solid grinding. Furthermore, the addition of iron can activate H2O2 more effectively to generate active oxygen which is •OH. The degradation experiments demonstrated that nearly 99.0% degradation efficiency was achieved for 10 mg/L Malachite Green (MG) solution within 60 min at the conditions of 0.10 g·L−1 MgAlFe-HTLcs, 0.10 mol·L-1 H2O2 and a natural pH of 6.3. Total organic carbon (TOC) removal reached 72.2% in a 70 min reaction. BET and XRD were measured to further discuss the stability and durability. Finally, a possible mechanism for the degradation of MG was presumed. [ABSTRACT FROM AUTHOR]

New energetic materials, [Ca(MCZ)3(H2O)2](ClO4)2and {[Ba2(MCZ)4(H2O)2(μ1-ClO4)2(μ2-ClO4)2]0.5}n, are synthesized and tried as alternatives to common primary explosives. Both the crystal structures were determined by single-crystal X-ray diffraction. The crystal of [Ca(MCZ)3(H2O)2](ClO4)2belongs to the monoclinic, P21/c space group,a = 14.168(3) Å,b = 8.5938(18) Å,c = 18.889(4) Å,β = 111.234(2)°,V = 2143.8(8) Å3,ρ = 1.6893 g cm−3, and {[Ba2(MCZ)4(H2O)2(μ1-ClO4)2(μ2-ClO4)2]0.5}nbelongs to the triclinic, P-1 space group,a = 7.166(2) Å,b = 10.461(2) Å,c = 11.738(4) Å,α = 110.563(5)°,β = 93.799(2)°,γ = 96.864(3)°,V = 812.4(4) Å3,ρ = 2.185 g cm−3. Their thermal stabilities were investigated by differential scanning calorimetry (DSC), and exothermic peak temperatures with a heating rate of 10 °C min−1are 249.7 and 181.7 °C, respectively. Non-isothermal reaction kinetics parameters were calculated via both Kissinger’s method and Ozawa-Doyle’s method to work outEK = 124.6 kJ mol−1, lgAK = 10.38,EO = 126.7 kJ mol−1for the calcium complex andEK = 100.3 kJ mol−1, lgAK = 9.50,EO = 102.6 kJ mol−1for the barium complex. Additionally, the critical temperatures of thermal explosion, ΔS≠, ΔH≠, and ΔG≠were calculated as −231.2 J K−1 mol−1, 120.417 kJ mol−1, 236.728 kJ mol−1for the calcium complex and −230.6 J K−1 mol−1, 96.723 kJ mol−1, 195.938 kJ mol−1for the barium complex. As for their explosive nature, sensitivities toward impact and friction were tested. Both [Ca(MCZ)3(H2O)2](ClO4)2and {[Ba2(MCZ)4(H2O)2(μ1-ClO4)2(μ2-ClO4)2]0.5}nare insensitive to friction (>360 N); their impact sensitivities are acceptable (20 and 13 J). Both compounds are energetic complexes. [ABSTRACT FROM PUBLISHER]

Two new ionic complexes, (DATr)2[Li2(TNR)2·2H2O]·2H2O (1) and (DATr)[Zn(DATr)Cl3] (2), were synthesized by using 3,4-diamino-1,2,4-triazole (DATr) as outer cation. X-ray single-crystal diffraction analysis revealed that the two complexes crystallize in triclinic and orthorhombic crystal systems, respectively. Differential scanning calorimetry was applied to assess the thermal decomposition behavior and kinetic parameters of decomposition were studied by using Kissinger’s and Ozawa–Doyle’s methods. Furthermore, the critical temperature of thermal explosion and parameters of thermodynamics were obtained. [ABSTRACT FROM PUBLISHER]

Both [Cu(DAT)2(PA)2] (1) and [Cu(DAT)2(HTNR)2] (2) were prepared from 1,5-diaminotetrazole (DAT) and copper trinitrophenol,1for picrate (PA) and2for styphnate acid (2,4,6-trinitro resorcinol, TNR), and were characterized by elemental analysis, FT-IR spectroscopy, and single crystal X-ray diffraction. The space group of these compounds isP21/c(monoclinic). The lattice parameters are similar [a = 11.405(3) Å,b = 14.867(3) Å,c = 8.099(2) Å for1anda = 12.262(3) Å,b = 14.900(3) Å,c = 7.243(2) Å for2], except theβ = 106.257(3)° in1andβ = 92.989(4)° in2. Both have extended structures due to hydrogen bonds, but there are some differences because of the ligands induced effect. Differential scanning calorimetry analysis shows that two exothermic processes take place in both complexes, the first peak temperatures are 488.2 K for1and 519.2 K for2. The kinetic parameters of the first exothermic process were studied by using Kissinger’s method and Ozawa’s method, in which the enthalpy of formation (−7346 and −5706 kJ M−1), critical temperature of thermal explosion (475.0 and 515.8 K), entropy of activation (ΔS≠), enthalpy of activation (ΔH≠), and free energy of activation (ΔG≠) were calculated and obtained as −117.25 J K−1 M−1, 140.64 kJ M−1, 196.44 kJ M−1and −219.1 J K−1 M−1, 383.56 kJ M−1, 495.34 kJ M−1for1and2, respectively. The sensitivity test results showed that both compounds were sensitive to impact (<5 J) and flame (>20 cm) rather than friction. Two similar complexes combined with 1,5-diaminotetrazole (DAT) and copper trinitrophenol were characterized by elemental analysis, FT-IR spectroscopy and single crystal X-ray diffraction and the sensitivity were studied. [ABSTRACT FROM AUTHOR]

Cadmium(II) imidazole (IMI) azide [Cd(IMI)2(N3)2]n(1) was synthesized using imidazole and azide, and was characterized by the elemental analysis and FTIR spectrum. The crystal structure was determined by X-ray single crystal diffraction, and the crystallographic data show that the crystal belongs toorthorhombic,Pba2space group,α = 10.780(4) Å,b = 13.529(5) Å, andc = 3.6415(12) Å. Its crystal density is 2.080 g·cm–3. Cd(II) is a six-coordinate with six nitrogens from four imidazoles and two azides withμ–1,1 coordination. The thermal decomposition mechanism was determined based on differential scanning calorimetry (DSC) and thermogravimetry-derivative thermogravimetry (TG-DTG) analysis, and the kinetic parameters of the first exothermic process were studied using Kissinger’s method and Ozawa’s method, respectively. The energy of combustion, enthalpy of formation, critical temperature of thermal explosion, entropy of activation (ΔS≠), enthalpy of activation (ΔH≠), and free energy of activation (ΔG≠) were measured and calculated. In the end, impact sensitivity was also determined by standard method. [ABSTRACT FROM AUTHOR]