US Patent 11993748 Tagging of fracking sand

Disclosed is a process for on- and off-site tagging of fracking sand and a composition of matter capable of being utilized in that process. The composition of matter includes a linker polymer conjugated to a rare earth particle. The method involves forming two mixtures, a first involving mixing a linker polymer conjugated to a rare earth particle into an aqueous blend of fracking sand, and a second involving an activated amine terminated polymer in an aqueous solution. The second mixture is then added to the first mixture, and covalent amide bonds are formed.