Samarium phosphate-cesium hydrogenophosphate

CATALYSIS BY RARE EARTH PHOSPHATE HI. CHARACTERISATION OF SAMARIUM PHOSPHATE AND SAMARIUM PHOSPHATE-CESIUM HYDROGENOPHOSPHATE AS KEY CATALYSTS FOR O-ALKYLATION OF PHENOLS... [Pg.62]

Samarium phosphates, impregnated or not by cesium hydrogenophosphate, selective catalysts for O-alkylation of phenols, have been characterised by various techniques. This study has shown that ... [Pg.62]

Particularly, a synergism between cesium hydrogenophosphate and samarium phosphate has been observed for the O-alkylation of dihydroxy-benzene (ref. 2). We described in this paper some characterizations of this solid doped or not, that may allow to explain catalytic results. [Pg.63]

Samarium phosphate was prepared by wet synthesis starting from samarium carbonate (Sm2(C03)3, originated RP). Precipitation of phosphate by phosphoric acid is conducted at 80°C by addition of a samarium carbonate suspension in a vessel containing phosphoric acid. After the end of the addition, the solid could be treated by ammonia at pH = 9. Cesium hydrogenophosphate is introduced by wetness impregnation of the dried (110°C) solid. [Pg.63]

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