反应详情

Further, the thus recovered 1110 g of phosphoric acid (lower layer (1)+lower layer (2)) contained 5.13 mol (503 g) of orthophosphoric acid and 0.01 mol (2.7 g) of monododecyl phosphate. 183 g (1.4 mol) of 75% phosphoric acid at the foods additive grade were supplemented to the recovered phosphoric acid and concentrated in the same manner as described above to obtain 606 g of 105.1% polyphosphoric acid (6.5 mol converted as orthophosphoric acid). The hue of the polyphosphoric acid showed no change at all, in the hue or the like as compared with that in the phosphoric acid used initially. Further, the polyphosphoric acid was used for the reaction in the same manner as above by dropwise addition into the n-hexane solution (243 g) of 243 g (1.3 mol) of dodecyl alcohol and hydrolysis was carried out. As the result of analysis, 1.275 mol (340.5 g) of monododecyl phosphate, 0.012 mol (5.2 g) of didodecyl phosphate and 5.21 mol (510.6 g) of orthophosphoric acid (99.0% alcohol conversion rate).