Industrial & Engineering Chemistry Research, Vol.55, No.7, 2059-2068, 2016
Preparation of High Purity Lead Oxide from Spent Lead Acid Batteries via Desulfurization and Recrystallization in Sodium Hydroxide
This paper reports a new method of direct recovery of highly pure lead oxide (PbO) from waste lead pastes and lead grids of spent lead acid batteries via catalytic conversion, desulfurization, and recrystallization processes in sequence. On the basis of the analytical results of lead (Pb) and lead dioxide (PbO2) contents in the scrap lead paste, a certain amount of waste lead grid was used as a reductant to transform the excess PbO2 into lead sulfate (PbSO4). This paper systematically studies the influence of the concentration of sulfuric acid (H2SO4) and catalyst and the reaction temperature on the catalytic process. The desulfurization of the obtained PbSO4 and the recrystallization of PbO in sodium hydroxide (NaOH) solutions of different concentrations are also investigated. Furthermore, electrochemical experimental results show that the prepared alpha-PbO with high purity provides slightly superior electrochemical performance to the existing lead oxide obtained by the Shimadzu ball-milling method during the first 350 charge-discharge cycles in the cycling test.