Bivalve Shell: Not an Abundant Useless Waste but a Functional and Versatile Biomaterial

Bivalve shells, available in abundance, have no eminent use and are commonly regarded as waste. Their improper disposal causes a significant level of environmental concern and also results in a waste of natural resources. Bivalve shell is formed by biomineralization and consists mainly of CaCO3 with a small amount of organic matrix, giving it a potential for use as raw material. Recycling shell waste could potentially eliminate the disposal problem, and also turn an otherwise useless waste into high value-added products. The present paper first describes the microstructure and physicochemical properties of bivalve shell, then focuses on its current applications. Finally, the current status of bivalve shell studies and directions for future research are considered.