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

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, high-performance 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 CoAl2O4 pigments with low cobalt consumption as well.