ABSTRACT
Metal nitrate complexes of general formula [M(dah)(2)](NO(3))(2) (where M=Zn, Cu and Ni; dah=1,6-diaminohexane) have been prepared and characterized by elemental analysis, infrared spectroscopy (IR) and gravimetric method. The thermal decomposition has been studied using thermogravimetry (TG). Simultaneous thermogravimetry-differential thermogravimetry-differential thermal analysis (TG-DTG-DTA) and differential scanning calorimetry (DSC) were done in N(2) atmosphere. Isothermal TG of initial decomposition of all these complexes, have been carried out to evaluate the kinetics of early thermolysis. Both, model fitting and isoconversional method have been used for the evaluation of the kinetics of thermal decomposition. Model fitting method have given the single value of activation energy (E) whereas, isoconversional method yields a series of E-value, which vary with extent of conversion. Ignition of the complexes was measured to see the response towards rapid heating with varying amounts. The thermal stability of the complexes was found to be in the order as [Zn(dah)(2)](NO(3))(2)>[Cu(dah)(2)](NO(3))(2) approximately [Ni(dah)(2)](NO(3))(2).
Subject(s)
Diamines/chemistry , Nitrates/chemistry , Temperature , Transition Elements/chemistry , Calorimetry, Differential Scanning , Kinetics , LigandsABSTRACT
Four complexes are prepared and characterized having molecular formula [Zn(dab)(2)](NO(3))(2), [Cu(dab)(2)](NO(3))(2).H(2)O, [Ni(dab)(2)](NO(3))(2).2H(2)O and [Mn(dab)(2)](NO(3))(2), where dab: 1,4-diaminobutane. Thermolyses of these complexes were investigated by simultaneous thermogravimetry (TG), derivatives thermogravimetry (DTG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC). The kinetics of the thermolysis at early stages is investigated using isothermal TG by applying model-fitting and isoconversional method. Thermolytic process is slow in inert (N(2)) and is fast in air atmosphere due to oxidative nature. To investigate the response of these complexes under the condition of rapid heating, ignition delay (D(i)) has been measured. Thermal stability of the complexes was found to increase in the order Mn < Cu < Ni < Zn.
Subject(s)
Hazardous Waste/prevention & control , Nitrates/chemistry , Putrescine/chemistry , Transition Elements/chemistry , Differential Thermal Analysis , Kinetics , Temperature , ThermogravimetryABSTRACT
The thermolysis of various substituted ammonium salts of nitric and perchloric acids has been reviewed in the present communication. The mechanistic aspects of thermal decomposition of these salts have been discussed critically. It has been observed that the proton transfer process do play a major role during thermolysis of these salts. The plausible decomposition pathways have also been described.
Subject(s)
Nitric Oxide/metabolism , Perchlorates/metabolism , Explosions , TemperatureABSTRACT
The thermolysis of high energetic polynitro organic compounds has been reviewed in the present communication.