| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject catalyst containing a rare earth element, enabling easy and efficient etherification in aqueous solvent without any specific catallyst separation-related process. SOLUTION: This catalyst to be used in the etherification contains at least one kind of compound selected from the group consisting of (I) rare earth element hydroxide, etc., and (II) compound produced by substituting OF group of the hydroxide with phosphate group. The compound in the group is represented by the formula M(OH)x .(O)y ' (PO4 )z (M is a rare earth element; 0<(x<=3; 0<=(y)<1.5;0 <= (z)<1). The hydroxide is produced by heating an aqueous solution of a rare earth element salt to 20-80 deg.C, adding NH3 or alkali, and precipitating the resulting hydroxide at >=pH10, preferably, >=pH12. The compound II is produced by mixing a rare earth element salt, orthophosphoric acid, etc., in aqueous solution at 20-80 deg.C and at around pH7 and adjusting to >=pH7.5, preferably, >=pH8 with NH3 , etc. |
