Docosanoic Acid → Sodium Behenate

Participants

Reaction Steps

88 kg of the recrystallized behenic acid, 461 L of distilled water, 49.2 L of a 5 mol/L aqueous solution of NaOH and 40.3 L of a 10 mass % solution of dodecylthiopolyacrylamide surfactant (BUN-1) were mixed and allowed to react at 80° C. for one hour under stirring to form a sodium behenate solution. Separately, 206.2 L of an aqueous solution (pH 4.0) containing 40.4 kg of silver nitrate was prepared and kept at 10° C. To 635 L of distilled water contained in a reaction vessel kept at 30° C. were added the entire volume of the above-mentioned sodium behenate solution and the entire volume of the aqueous silver nitrate solution under sufficient stirring at constant flow rates over the periods of 93 minutes and 15 seconds, and 90 minutes, respectively; in this operation, only the aqueous silver nitrate solution was added during a period within 11 minutes from the initiation of the addition of the aqueous silver nitrate solution, and then the addition of the sodium behenate solution was started, and then the addition of the aqueous silver nitrate solution was completed, so that only the sodium behenate solution was added during a period within 14 minutes and 15 seconds from the completion of the addition of the aqueous silver nitrate solution. In this operation, the outside temperature was controlled so that the temperature in the reaction vessel was maintained at 30° C. and the liquid temperature was kept constant. The pipe of the addition system for the sodium behenate solution was warmed by circulating warmed water in the space between the outer pipe and the inner pipe of a double pipe, and temperature was controlled such that the liquid temperature at the outlet orifice of the addition nozzle was 75° C. The pipe of the addition system for the aqueous silver nitrate solution was maintained at a constant temperature by circulating cold water in the space between the outer pipe and the inner pipe of a double pipe. The addition position of the sodium behenate solution and the addition position of the aqueous silver nitrate solution were arranged symmetrically with respect to the stirring axis as a center, and the positions had such heights as not to contact with the reaction solution.

Provenance & Evidence