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A heteropoly molybdoselenite complex (NH_4)_6[Se_2Mo_8O_ 31 ]·5H_2O and its lanthanide salts Ln_2[Se_2Mo_8O_ 31 ]·xH_2O(Ln=La 3+ , Ce 3+ , Nd 3+ , Sm 3+ ) were synthesized and characterized with elemental analysis, IR, UV, XRD and TG-DTA. Their reactivity for hydroxylation of phenol was investigated. The results show that catalytic activity of (NH_4)_6[Se_2Mo_8O_ 31 ]·5H_2O is higher than that of its lanthanide salts. The reaction temperatures, the reaction time, the catalyst amount, the ratio of phenol and H_2O_2 have influence on the phenol conversation, H_2O_2 selectivity and product distribution. The optimum reaction condition was obtained with orthogonal method. At optimum reaction condition which the ratio of phenol and H_2O_2=1∶1, reaction time is 4 h, reaction temperatures is 70 ℃ and catalyst is 10 g·mol -1 , and the conversation of phenol reaches as high as 29.65%, the product selectivity can reach 77.2% for catalyst (NH_4)_6[Se_2Mo_8O_ 31 ]·5H_2O.
A heteropoly molybdoselenite complex (NH_4) _6 [Se_2Mo_8O_31] · 5H_2O and its lanthanide salts Ln_2 [Se_2Mo_8O_31] · xH_2O (Ln = La 3+, Ce 3+, Nd 3+, Sm 3+) were synthesized and characterized with elemental The results show that catalytic activity of (NH_4) _6 [Se_2Mo_8O_31] · 5H_2O is higher than that of its lanthanide salts. The reaction temperatures are hydroxylation of phenol was investigated. , the reaction time, the catalyst amount, the ratio of phenol and H 2 O 2 have influence on the phenol conversation, H 2 O 2 selectivity and product distribution. At optimum reaction condition was the ratio of phenol and H 2 O 2 = 1: 1, reaction time is 4 h, reaction temperatures is 70 ° C and catalyst is 10 g · mol -1, and the conversation of phenol reaches as high as 29.65%, the product selectivity can reach 77.2% for catalyst (NH_4) _6 [Se_2Mo_8O_31] · 5H_2O.