Solubility of Litharge (a-PbO) in Alkaline Media at Elevated Temperatures

[摘要] An inert, flowing autoclave facility is used to investigate the solubility behavior of {alpha}-PbO (litharge, tetragonal) in aqueous solutions of morpholine, ammonia and sodium hydroxide between 38 and 260 C. Lead solubilities increased from about 0.4 mmol kg{sup -1} at 38 C to about 4.5 mmol kg{sup -1} at 260 C and were relatively insensitive to the concentration and identity of the pH-reagent. The measured lead solubilities were interpreted using a Pb(II) ion hydroxocomplexing model and thermodynamic functions for these equilibria were obtained from a least-squares analysis of the data. A consistent set of thermodynamic properties for the species Pb(OH){sup +}, Pb(OH){sub 2}(aq) and Pb(OH){sub 3}{sup -} is provided to permit accurate lead oxide solubility calculations over broad ranges of temperature and alkalinity.

[发布日期] 2004-11-02 [发布机构] Lockheed Martin

[关键词] Acid Neutralizing Capacity;Sodium Hydroxides;Aqueous Solutions;Lead Oxides;Solubility