Synthesis and characterization of anticorrosion, low-lead leaching PbCrO4/eggshell composites as the environmentally sustainable yellow pigments

The hazardous effects of PbCrO4 were the motivation for investigation of the possible us of low-lead leaching PbCrO4 based pigments. Eggshell, as the strong low-cost adsorbent of lead, is a suitable choice for the synthesis of low-lead leaching PbCrO4/eggshell composite pigments. Starting from this point, in this work, a series of composite pigments, X-PbCr/ES (X = 10, 30, 40, 50), consist of different weight percentages of PbCrO4 and eggshell powder as an inexpensive waste were prepared. A range of compositions was prepared and characterized. The composite pigments showed good yellow color, with the b* value using the CIELAB 1976 system being around 80. PbCr/ES composites are semiconductors with band gaps of 2.3-2.4 eV. The leaching stability of the pigments was investigated in natural, acidic, and alkali aqueous solutions. The release of Pb(II) in acidic solution was higher than natural and alkali solutions. The presence of NaCl also favors the leaching process. These pigments showed significantly lower lead leaching levels in comparison with PbCrO4. The corrosion efficiencies of the pigments were studied using electrochemical impedance spectroscopy. The PbCr/ES pigments showed good corrosion performances related to the diffusion resistance of eggshell and the corrosion inhibition of PbCrO4. The low-lead leaching of the composite pigments coupled with their anticorrosive behavior makes the developed pigment ideal as the alternative to PbCrO4-based pigments with a wide variety of applications. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

The study investigated the use of low-lead leaching PbCrO4/eggshell composite pigments as an alternative to PbCrO4-based pigments. The composite pigments exhibited good yellow color and semiconductor properties, with significantly lower lead leaching levels compared to PbCrO4. Additionally, they showed good corrosion resistance, making them ideal for various applications.