Enhancing the phosphorus content of layered double hydroxide fertilizers by intercalating polymeric phosphate instead of orthophosphate: A feasibility study

The P adsorption capacities were 1.25-1.60 fold larger for PO compared to PO, yet the high theoretical P contents with PO were not achieved (incomplete loading, PO depolymerization). PO-MgAl released polymeric-P whereas PO-MgAl released depolymerized PO, and P release from PO-LDHs was slower than that of PO-LDHs. With soil incubation, soluble P from PO-LDH was initially lower but later converged to that of PO-LDH as result of continued hydrolysis, yet did not exceed that of the soluble PO and PO fertilizers.