蒸气浸渍法制备完全无氯CuY催化剂及其氧化羰基化性能

以具有升华性质且易分解的乙酰丙酮铜为铜源，NH₄Y分子筛为载体，采用蒸气浸渍法制备了CuY催化剂，考察了其对甲醇氧化羰基化合成碳酸二甲酯的催化性能，并采用XRD、H₂-TPR和NH₃-TPD等表征手段研究了催化剂上铜物种的分散状态、催化活性中心的含量及催化剂的酸强度和浓度，发现铜物种在Y分子筛载体上高度分散，且Y分子筛载体的晶体结构保持完好。在N₂∶H₂=12∶1的气氛中，250℃还原得到的催化剂CuY/250催化活性中心含量最高，催化活性也达到了最佳，其甲醇转化率为11.1%，碳酸二甲酯的时空收率和选择性分别为200.5mg/(g·h)和60.3%。

Preparation of chlorine-free CuY catalysts by vapour impregnation and their application for oxidative carbonylation

CuY catalysts were prepared by vapour impregnation with copper acetylacetonate as the copper source and NH₄Y zeolite as the support. The performance of the catalysts was evaluated by using direct vapor-phase oxidative carbonylation of methanol to dimethyl carbonate (DMC) as a model reaction. The surface dispersion, active component content, acid strength and concentration of the as-prepared catalysts were characterized by X-ray diffraction (XRD), H₂-temperature programmed reduction (H₂-TPR) and NH₃-temperature programmed desorption (NH₃-TPD), respectively. It was found that copper species were highly dispersed on the Y zeolite and the crystal structure of the Y zeolite remained intact. For the CuY/250 catalyst activated at 250℃ and in the atmosphere of N₂∶H₂=12∶1, the active component content was the highest and the catalytic activity was excellent. The obtained methanol conversion, space time yield and selectivity of dimethyl carbonate were 11.1%, 200.5mg/(g·h) and 60.3% respectively.