REGULARITIES OF CONJUGATED HETEROPHASE CHEMICAL CONVERSION OF COPPER SULFATE BY THE METHOD OF THE EFFECT OF GAS-PHASE CHAIN REACTIONS

Abstract

Chemical conversions of typical ion compound – copper sulphate are studied under the effect of gas-phase chain reaction (CRE regime) of hydrocarbon oxidation. The regularities pointing at non-trivial and complex principles for proceeding of inorganic compound conversion under CRE conditions have been detected. The process has been studied at flow condition of propane-n-butane oxidation gas phase chain reaction. The sample of waterless copper sulphate was placed in a quartz vessel (reactor). Experiments were carried out at a wide range of parameters – temperature, contact time of the gas-phase reaction (flow velocity), the value ratio of hidrocarbon (RH) and oxygen (O2) in gaseous mixture (RH:O2), exposure time. In the first part, the experimental results and their discussion refer to the interaction of CuSO4 with only hydrocarbon gases (non-chain conversion). Part second presents the results and conclusions related to the process of effect CuSO4 to a gas phase chain reaction of hydrocarbon oxidation (conjugated chain conversion of CuSO4), as well as the comparison of the regularities of the two studied processes. CuSO4 was shown to be undergone intensive conversion under the effect of chemical chain reaction-up to reduction to metallic copper in the form of fine powder. The process realized by the CRE method is characterized by essentially low temperatures and high rates of reaction compared with the one realized only under the effect of hydrocarbon gases. In case of the CRE regime, activation energy is ECRE=63,4 kJ/mol, while in case of

hydrocarbon acting alone – ERH=134,7 kJ/mol. Calculations show that chemical interactions of CuSO4 with hydrocarbon-oxygen mixture reacting by chain mechanism, are efficient in thermodynamic aspect also. It was established that depending on the process conditions, Cu, Cu2O, CuO, 2CuCO3Cu(OH)2 of certain crystal structures may be the products of reactions (separately as well). The conversion heterophase process is influenced by such parameters characteristic for reactions proceeding by the chain mechanism as the ratio of gaseous reagents, contact time, etc. The products of conversion obtained in various modes of the CRE process are paramagnetic ones which could make them applicable for different purposes (e.g. in catalysis). These results also show the complicated nature of this conjugated radical-chain process. CuSO4 processing by the CRE method, on the whole, may be of important practice for the production of pure copper and for pure and super-pure fine powder of copper-containing compounds, as well as for the development of effective ways for processing of complex copper compounds.