Thermal and chemical stability of Cu–Zn–Cr-LDHs prepared by accelerated carbonation

Layered double hydroxides CuxZn6 − xCr2(OH)16(CO3)·4H2O with different molar ratios of Cu/Zn/Cr were synthesized by accelerated carbonation. The products were characterized by XRD, SEM, FT-IR and TG-DTG-DSC-MS. The chemical stability was tested by the modified Toxicity Characteristic Leaching Procedure (TCLP). The results showed that the products were the mixture of CuxZn6 − xCr2(OH)16(CO3)·4H2O and (CuZn)2(CO3)(OH)2, with similar thermal behavior. All products were chemically stable with reduced leaching at pH > 6 (Cu2+, Zn2+) or > 5 (Cr3+).