Utilization of Sea Sand for Preparation of High-Performance CoAl₂O₄ Composite Pigments via a Cleaner Mechanochemistry Route

Abstract

Exploitation and utilization of low-value natural mineral resources in a feasible way are promising under the background of green sustainable development. In this study, highperformance cobalt blue composite pigments with low cobalt consumption were facilely fabricated based on sea sand via a cleaner mechanochemistry route followed by a calcining process. It was revealed that cobalt blue nanoparticles were loaded on the surface and near edge areas of quartz in sea sand. The desirable blueness was related to the improved dispersion of cobalt blue nanoparticles as well as the strengthened reflection to blue light by quartz. In addition, the removal of existing Fe species in sea sand had a positive effect on the blue intensity of composite pigments. The prepared composite pigments based on original sea sand presented an excellent acid resistance and color performance, which were sufficient to satisfy the needs of the related fields. Therefore, this study is expected to develop a feasible and cleaner strategy for the direct value-added utilization of sea sand and propose a novel design for the construction of high-performance CoAl 2 O 4 pigments with low cobalt consumption as well.

Sustainable utilization of natural sands for cleaner preparation of high-performance nanostructured cobalt blue composite pigments by dolomite-induced mechanochemistry

“…However, the composite pigments showed some diffusion phenomenon, which might be due to the formation of an Al 2 O 3 -CoAl 2 O 4 solid solution during the calcination process. 23 Therefore, the prepared composite pigments presented benign application prospects as high-temperature ceramic pigments.…”

“…In our previous study, commercial synthetic heavy CaCO 3 was developed for the assisted preparation of CoAl 2 O 4 composite pigments by a mechanochemical method in the presence of natural sea sand and desert sand. 23,24 However, it neglected the effect of Ca 2+ derived from CaCO 3 on the color properties of CoAl 2 O 4 composite pigments, and most of them were removed by water aer being transferred from a grinding jar. As a typical Ca-and Mg-bearing carbonate mineral, dolomite (CaMg(CO 3 ) 2 ) is widely distributed in sedimentary rocks on the Earth, including continental lacustrine and marine settings.…”