Abstract: Hydrotalcite-like compounds containing carbonate ion as the interlayer anion wereprepared by coprecipitation under low supersaturation condition by mixing an aqueous solu-tion of metal nitrates with an aqueous solutions of NaOHand Na₂CO₃ at room temperature,maintaining pH =8-10 with vigorous stirring- Following the mixing, the resulting heavyslurry was aged at 353 Kfor 18 h with vigorous stirring, The precipitate was then filtered,washed several times with hot distilled water and dried in air at 353 Kovernight. In thisway, CuM1 AlCO₃-HTLcs and M1 AlCO₃-HTLcs were synthesized and characterized bymeans of XRDand lR. The catalysis of the above mentioned HTLcs were investigated in thephenol hydroxylatlon with H₂O₂. The results indicated that all of the copper-containingHTLcs had a higher catalytic activity in the reaction. However, those catalysts that did notcontaln copper had no catalytlc actlvlty in this reaction- This means that copper was the ac-tive center in the phenol hydroxylation. Meanwhile, the mechanism was also proposed,which could be used to explain the main reason for higher activity for CuCuAlCO₃-HTLcs inthe phenol hydroxylation and the effect of Mg²⁺, Zn²⁺, Co²⁺, Ni²⁺ on activlty of CuM¹ Al-CO₃-HTLcs.

Key words: Hydrotalcite, Transition metal, Phenol hydroxylation, Hydrogen peroxide, Catalysis