Conditions for the hydrolysis of nitriles by calcium hydroxide

Both hydrolysis and alcoholysis can take place under the catalysis of acid or base; during hydrolysis, an amide is formed first, followed by a carboxylic acid. During alcoholysis, if it is completely anhydrous, imide esters are formed (the oxygen in the ester is replaced by an imide group; salts are obtained under acidic conditions), while esters are formed in the presence of water. Under acid catalysis, it can form salts with the ammonia (or amines) produced, thereby facilitating the reaction to proceed in the forward direction ； Under basic catalysis, it cannot form a salt with the resulting ester; moreover, if NaOH is used, the ester formed is prone to hydrolysis, while using the corresponding sodium alcohol yields higher costs.

Alkali hydrolysis of acrylic fiber can also occur in a strong alkaline medium; under the action of substances such as sodium hydroxide, potassium hydroxide, water glass, trisodium phosphate, tripotassium phosphate, sodium sulfide, ammonia water, and calcium hydroxide, hydrolysis takes place. Sodium hydroxide is generally the most commonly used catalyst for this process. The alkaline hydrolysis process is similar to the acidic hydrolysis: the -CN group is first hydrolyzed to -CONH2, and then further hydrolyzed to the -COONa group, accompanied by the release of N2 gas. Due to the electrostatic repulsion between adjacent groups on the polymer chain, the yield of carboxyl groups obtained through alkaline hydrolysis cannot reach 100%4; moreover, the content of polyacrylate groups varies depending on the reaction conditions. The main factors affecting the carboxyl group yield include time, temperature, alkali to silk ratio, and water to silk ratio.

Thank you for your explanation; I now fully understand the hydrolysis process. However, I’m more interested in knowing the conditions under which the cyano group is hydrolyzed in the presence of calcium hydroxide For example, the hydrolysis temperature, pressure, concentration of hydrolysis, hydrolysis time, and whether a catalyst is added as well? Thank you