4 parts of 0.1% bromocresol green methanol solution and 1 part of 0.1% methyl red sodium salt aqueous solution were mixed as mixed indicators. A 250m1 flask contains 50mL of water, 0.4mL of the above mixed indicator is added, and 0.1moI/L hydrochloric acid is added dropwise to neutralize to green. Accurately weigh 1.4～1.6g of sample, add it into the flask, and mix well. With 0.5mol/L hydrochloric acid titration to green. 0.5mol/L hydrochloric acid is equivalent to C4H9NO 43.56mg per ml.

N- methylmorpholine is mainly used in the production of rubber vulcanization accelerator, and also used in the synthesis of surfactants, textile printing and dyeing auxiliaries, medicines and pesticides. Morpholine is also used as catalyst, corrosion inhibitor and optical bleaching agent for butadiene polymerization. Morpholine is also a solvent for dye, resin, wax, gum, casein, etc.

Morpholine salts are also widely used, and morpholine hydrochloride is an intermediate of organic synthesis. Morpholine fatty acid salt can be used as a coating agent for the epidermis of fruits or melons and fruits, which can properly inhibit the respiration and prevent the evaporation of water and the atrophy of epidermis.

Jiangsu Lianrun Chemical Co., Ltd.: Focus on the research and production of fine chemical products with high scientific and technological content, such as 14 dioxane and N- methylmorpholine with high purity!