PbSO4 Leaching in Citric Acid/Sodium Citrate Solution and Subsequent Yielding Lead Citrate via Controlled Crystallization

Abstract

Lead citrate is a key precursor for the green recycling of spent lead acid battery paste in a citric acid/sodium citrate (CA/SC) solution. In this study, the main paste component, PbSO 4 , was leached and crystallized to yield lead citrate. Results showed that the leaching of PbSO 4 in citric acid/sodium citrate solution was remarkably enhanced by an increase in temperature from 35 • C to 95 • C and an increase in sodium citrate (SC) concentration from 50 to 650 g/L. In comparison, increasing the citric acid/sodium citrate molar ratio inhibited this leaching. Controlled crystallization through cooling the solution or adjusting the pH of the solution can effectively produce lead citrate crystals. The X-ray diffraction patterns of four products obtained in a comparison test were all consistent with Pb 3 (C 6 H 5 O 7 ) 2 . However, the scanning electron microscopy analysis suggested that the morphology was distinct from rods to sheets, which were mainly affected by the temperature variation.

Estudio termodinámico de la lixiviación de plomo reciclado con citrato de sodio

“…Cuando aumenta la concentración de agente lixiviante la extracción disminuye a 80%, el cual industrialmente sigue siendo un valor atrayente. Los anteriores resultados indican que la actividad iónica es más alta a bajas concentraciones comparadas con las características de una solución con altas concentraciones, sin embargo, si domina el consumo de citrato de sodio en la reacción hidrolítica, la reacción compleja puede debilitarse o retardarse, lo que conduciría a un efecto inhibidor sobre el comportamiento del agente lixiviante [8,6]. En la Figura 8 se observa una disminución de extracción metálica y una menor influencia de la concentración de agente lixiviante en el proceso hidrometalúrgico; la extracción más alta (90%) se obtuvo para una relación sólido líquido 10:1 a 0.25 y 0.5 M de citrato; mientras que para una concentración de citrato 1 M se obtuvo 85%.…”

“…En este artículo se desarrolló un análisis termodinámico del agente lixiviante citrato de sodio (Na 3 C 6 H 5 O 7 •2H 2 O) [5,6]; para la extracción de plomo obtenido de baterías de automóvil recicladas. El trabajo se llevó a cabo mediante el uso de técnicas mecánicas para el procesamiento de materiales, en conjunto de procesos químicos implementados en la hidrometalurgia.…”

A Facile and Environmentally Friendly Approach for Lead Recovery from Lead Sulfate Residue via Mechanochemical Reduction: Phase Transformation and Reaction Mechanism

“…Although the reaction temperature dropped significantly, still sulfur dioxide escaped due to the low desulfurization efficiency . Comparatively, sufficient conversion of sulfur can be achieved using hydrometallurgical technologies with various aqueous systems, including chlorine salts, , alkaline solutions (sodium carbonate, ammonium carbonate, sodium hydroxide, and so on), − and organic acids. , Ye et al extracted lead from bioleaching residue tailings using sodium chloride successfully, based on the solubility of complexation chlorides. Buzatu et al studied the mathematical modeling of the sodium hydroxide leaching process, improving the leaching efficiency of lead sulfate.…”

“…18 Comparatively, sufficient conversion of sulfur can be achieved using hydrometallurgical technologies with various aqueous systems, including chlorine salts, 19,20 alkaline solutions (sodium carbonate, ammonium carbonate, sodium hydroxide, and so on), 21−23 and organic acids. 24,25 Recently, an alternative approach based on mechanochemistry for materials synthesis, 26−28 waste treatment, 29 and metal alloying, has received considerable attention due to its ecofriendliness and moderate operating conditions. Mehrabani et al demonstrated the preparation of metallic tungsten from scheelite via co-grinding with magnesium, revealing the positive effect of mechanochemistry on the chemical reduction.…”

Cleaner Extraction of Lead from Complex Lead-Containing Wastes by Reductive Sulfur-Fixing Smelting with Low SO2 Emission

“…Many studies about the treatment of Pb-containing wastes using pyrometallurgical and hydrometallurgical processes were reported in recent years [12,13]. The immobilization of lead slags to prepare construction materials and inorganic polymers were also investigated [14,15].…”