As a very important product of fine chemical products, morpholine can be used not only as a vulcanization accelerator for the preparation of NOBS, OTOS, but also as a preservative, detergent, local anesthetic, fruit preservative, detergent, analgesic Drugs, etc., and morpholine are widely used in medicine, pesticides, rubber, paints and other fields.
The morpholine production methods mainly include the diethanolamine method and the diethylene glycol method. The diethanolamine method is a traditional production method, and the required diethanolamine raw materials are solved by imports, and the price is high, the reaction yield is low, the production cost is high, and the products are not competitive;
Glycerol method is a newly developed morpholine production process in recent years. Diethylene glycol and liquid ammonia are used as raw materials, the process is simple, the conversion rate is high, and the source of diethylene glycol is sufficient. Especially, the development of morpholine in ammonia plants is more liquid ammonia and hydrogen. Advantage, the existing domestic 2/3 manufacturers use this method to produce morpholine.
With the rapid development of China's rubber industry, especially the tire industry, it stimulated and promoted morpholine production. Morpholine has become a hot chemical product in China. Many scientific research institutes have conducted a lot of research on its synthesis technology, and it has created an upsurge of morpholine construction in China. At present, China's morpholine not only has a big leap in the quantity and quality of products, but also the synthesis technology is improved from traditional diethanolamine acid dehydration method to the commonly used diethylene glycol catalytic hydrogenolysis cyclization method in foreign countries. Consumption has reached the international advanced level, but due to the large number of SMEs, the production technology and product quality are still uneven.
At present, the total annual production capacity of morpholine in China has reached 8,700 tons. However, due to technical reasons, three of them are in the state of production suspension or semi-discontinuation, so the actual output is not large, and many products are imported every year. According to statistics, the total demand for morpholine in China reached 7,000-8,000 tons in 2001. In recent years, with the continuous advancement of science and technology, the new use of morpholine has been continuously explored. For example, new types of pesticides and pharmaceuticals have been continuously developed and produced, and alkyl morpholine is used in the research and development stage of solvents in the chemical fiber industry.
Dozens of drugs can be synthesized using morpholine as raw materials, such as painkillers, local anesthetics, sedatives, respiratory system and vasodilators. China's morpholine is mainly used for the synthesis of morpholinium, ibuprofen, naproxen, dichloroaniline, sodium phenylacetate and so on. At present, the pharmaceutical industry consumes about 800 tons of morpholine annually. As these drugs are traditional drugs, the demand cannot be increased rapidly. The demand for morpholine in 2005 is expected to be about 1,100 tons.
Morpholine is used as a metal corrosion inhibitor and is mainly used for the corrosion protection of metals such as iron, copper, zinc, and lead. China is currently in its infancy. In terms of solvents, surfactants, optical brighteners, textile auxiliaries and catalysts, China started late.
Morpholine is mainly used for synthetic rubber vulcanization accelerators (NOBS, OTOS, 26). Among them, it is mainly used for the synthesis of NOBS. Before the 1990s, the consumption of rubber vulcanization accelerators in Europe, the United States, Japan and other developed regions accounted for more than 50% of the total demand for morpholine. At present, over 30% of China's consumption is used for N OBS. In recent years, international attention has been paid to the toxicity of accelerators that are prone to produce harmful nitrosamines during the rubber processing process. Many restrictive regulations around the world have been introduced in succession. For example, as early as in 1982, Germany promulgated regulations to control nitrosamines, the United States Japan, France, and the United Kingdom have actively developed new vulcanization accelerators that do not produce nitrosamines, and have stopped using vulcanization accelerators that produce nitrosamines. Therefore, foreign morpholine consumption decreases year by year with the ban of accelerator NOBS. Although China has no corresponding regulations to ban the accelerator NOBS, but China has joined the WTO, due to the entry of a large number of foreign tires, the need for localization of additives, but also require China's rubber vulcanization accelerator environmental protection, the use of non-toxic accelerators to replace NOBS has The general trend. In recent years, the demand for NOBS in China has been significantly reduced. According to the “Tenth Five-Year Plan” of national rubber additives, by 2005 China will basically not use secondary amine accelerators that can decompose nitrosamines. If NOBS is banned in China and production is stopped, the production and market of morpholine will be seriously affected.
According to the current development trend, the consumption of morpholine in the non-rubber adjuvant field in 2005 will not exceed 4,000 tons. Therefore, the situation of oversupply of morpholine will emerge, and many countries have already banned their toxic promoters. The morpholine also has excess levels and will not be imported from China. The prospect of morpholine development is worrying.
At present, morpholine production in China has been able to meet the market demand. Therefore, it is not appropriate to build new installations, and to improve and improve the existing facilities, focus on improving product quality, reduce costs, and promote the development and application of other downstream products with high quality and low prices. Many domestic morpholine devices produce products of low purity, and at the same time lead to a decline in the quality of accelerators. Therefore, high-purity pharmaceutical grade products should be developed in the future.
A considerable proportion of foreign morpholine is used for metal corrosion inhibitors, mainly as a metal gas rust inhibitor, to prevent metal from atmospheric corrosion, and has been widely used in mechanical instruments, automobiles, medical equipment and other fields, China has just started in this regard. The metal atmospheric rust inhibitors used at home and abroad, including dicyclohexylamine nitrite and cyclohexylamine nitrite, are toxic to the human body and the environment, constraining the popularization and application of vapor phase rust inhibitors, and morpholine as a metal gas and liquid corrosion inhibitor. With low toxicity and good development prospects. With the development of China's petrochemical industry, it will provide high-quality and low-cost raw materials for morpholine production, and the price of morpholine will decline accordingly, which will facilitate the application of metal corrosion protection. In addition, morpholine can also be used for pH regulators, gas absorbents, synthetic herbicides, etc. Domestic should also increase development and research efforts to promote morpholine consumption.
Recent years, the rapid development of new polymer monomer acryloline morphine is also worthy of attention. Acrylomorpholine is obtained by the reaction of acrylate and morpholine, used for the modification of aqueous polymer, and has good compatibility with various prepolymers and multifunctional acrylamides. As application research continues to deepen, many new specific uses will continue to be explored.
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