Key words: svinec, okislenie, vodokislorodnyj flyuid, peroksid vodoroda
The paper presents the research results of the oxidation of bulk lead samples with oxygen, water vapor, water-oxygen mixture, and hydrogen peroxide solution during heating of the reactor at a rate of 1 K/min up to 873 K under the conditions of high reactant density (ρН2О ≤ 4,58 и ρO2 ≤ 0,58 моль/дм3). The smallest gain in the weight of the samples was detected during the oxidation of lead with water vapor and oxygen, and the largest one, with the H2O/O2 mixture. It follows from the time dependences of the temperature and pressure of the reaction mixture that oxidation of lead by the H2O/O2 mixture noticeably accelerates at T > 425 K. An increase in the O2 content in the mixture and a decrease in the water vapor density intensify the oxidation. According to the X-ray diffraction analysis data, Pb3O4 (minium) predominates in the composition of lead oxidation products formed in the H2O/O2 mixture. It has been revealed that the size and morphology of oxidized lead particles depend on the composition of the reaction mixture. The mechanisms of lead oxidation are discussed.
doi:10.34984/SCFTP.2023.18.3.002