Methyl methacrylate (MMA)

Methyl methacrylate (MMA)
I. Product use Methyl methacrylate (MMA) is an important organic chemical raw material and chemical product, which is mainly used to produce PMMA, PVC auxiliary ACR, methyl methacrylate styrene butadiene copolymer (MBS), as well as resin, adhesive, coating, ion exchange resin, paper polish, textile printing and dyeing auxiliary, leather treatment agent, lubricating oil additive, crude oil pour point depressant, sizing agent for wood and softwood, soaking agent for motor coil, insulation pouring material, plasticizer for plastic lotion, etc. It is widely used. 2、 Market Overview As of 2015, the total domestic MMA production capacity reached 740000 tons/year, with a production of 420000 tons/year and a cumulative import volume of 210000 tons, a year-on-year decrease of 23.6%. The apparent consumption was 600000 tons/year, with an annual growth rate of about 7%, which is basically equivalent to the GDP growth rate. The industry has entered a mature stage of development. In 2016, with the commissioning of facilities such as Jiangsu Silbang and Wanhua, production capacity will continue to increase, mainly through substitution. 3、 There are three production methods for MMA in foreign countries, namely the ACH method (acetone cyanohydrin method) developed by ICI in the 1930s, the isobutene/tert butanol direct oxidation method (isobutene method) developed by Japanese catalyst in the early 1980s, and the ethylene propylene aldehyde method developed by BASF in the late 1980s. 80% of the global MMA production capacity uses ACH process, 15-20% uses isobutene process, and the ethylene propylene aldehyde process has a capacity of only 35000 tons per year, accounting for less than 2%. At present, the production of MMA in China mainly relies on the traditional ACH method. Due to limitations in raw materials and safety and environmental issues with hydrogen cyanide, this process has high production costs and cannot compete with imported products from abroad. In addition, due to the high demand for ethylene in China and the harsh transportation and storage conditions, the conditions for synthesizing MMA using the ethylene route are not yet mature. The direct oxidation technology of isobutene developed by our company has the advantages of high catalytic activity, good selectivity, low environmental pollution, and good economic benefits compared to other processes. It is suitable for the construction of industrial plants with a scale of 20000 to 50000 tons per year. Especially with the development of MTBE and cracking technology, a broad source of raw materials has been provided for the isobutene oxidation process. 4、 The brief process involves the vaporization of isobutene (or tert butanol) and air passing through the first and second oxidation reactors to produce a mixture of methacrylic acid. After cooling down, the reaction mixture enters the methacrylic acid absorption tower. Cool with circulating spray water to obtain a 20-30% aqueous solution of methacrylic acid, which is then sent to the methacrylaldehyde stripping tower to recover the methacrylaldehyde (MAL) and send it back to the oxidation reaction section. The separation and purification process of methyl acrylic acid aqueous solution adopts the method of countercurrent extraction of methyl acrylic acid aqueous solution and mixed solvent, followed by distillation. Under optimized process conditions, the extracted phase is subjected to vacuum desolvation, light component removal, and heavy component removal to obtain high-purity methyl acrylic acid (MAA) product. Methacrylic acid, methanol, and recovered MAA methanol enter the reactor for esterification reaction. The esterification reaction product is extracted and separated into MMA solution and methanol, and methanol is recycled back to the esterification reaction. The MMA solution passes through the heavy component removal tower, light component removal tower, and purification tower to obtain high-purity methyl methacrylate (MMA) product.