负载型磷钨酸催化剂的制备表征及其催化性能

PREPARATION AND CHARACTERIZATION OF SUPPORTED PHOSPHOTUNGSTIC ACIDS CATALYST AND ITS CATALYTIC PERFORMANCE

以拟薄水铝石为载体、磷钨酸为主催化剂,制备了负载型磷钨酸催化剂,并对其进行了金属镧(La)改性。采用XRD、NH3-TPD、SEM等手段对La改性负载型磷钨酸催化剂进行表征。通过对磷钨酸溶脱率的测定,考察负载型磷钨酸催化剂的负载强度。将该催化剂用于对羟基苯甲酸乙酯和己二酸的合成,考察其酸催化和氧化催化性能。结果表明,在磷钨酸的负载量为30%时,该负载型磷钨酸催化剂可重复使用7次,总的溶脱率为11.9%。在催化对羟基苯甲酸乙酯和己二酸的合成反应中,产率分别达到85.6%和95%。该催化剂是一种负载强度高、酸催化和氧化催化性能均良好的环境友好型催化剂。

One supported phosphotungstic acid catalyst was prepared, in which La modified pseudoboehmite was used as carrier and phosphotungstic acid （H3PW12 O40· nH2O, PW12） as active constituent. The prepared catalyst was characterized by the means of XRD, NH3-TPD, SEM. The supported strength of the catalyst was investigated through measuring the PW12 dissolution rate. When the loading of PW12 on the supported phosphotungstic acid catalyst was 30%, the total PW12 dissolution rate was 11. 9% after being recycled 7 runs. The acid and oxidation catalytic performances of the prepared catalyst were also evaluated through the syntheses of ethyl p-hydroxybenz-oate and cyclohex-anone, whose productions reached 85.6 % and 95 %, respectively. The results showed that the catalyst was a kind of environmental friendly catalyst with high supported strength, good acid and oxidation catalytic activities.