1. Purpose and market conditions
1.1 Uses of isopropyl alcohol
Isopropyl alcohol (IPA for short) is also known as sec-propyl alcohol and dimethylmethanol. CAS number 67-63-0 is an isomer of n-propyl alcohol. It is a colorless and transparent liquid, similar to ethanol. It smells like a mixture of acetone and water, and is soluble in most organic solvents such as water, alcohol, ether, benzene, and chloroform. It is an organic solvent with excellent performance and is widely used as a solvent for shellac, nitrocellulose, alkaloids, rubber, and grease. Solvent. Isopropyl alcohol is also an important intermediate in the preparation of a variety of organic compounds. It can be used as a raw material for the synthesis of isopropylamine, glycerol, isopropyl acetate, acetone, etc. It is also widely used as an antifreeze additive for petroleum fuels and is used in automobiles and aviation. fuel and many other aspects. In addition, isopropyl alcohol is also used to make detergents, bactericides, insecticides and disinfectant preservatives. It can be used alone or in combination with other alcohols and surfactants. It is used in pesticides, electronics industry, medicine, coatings, etc. It has a wide range of uses in the fields of daily chemicals and organic synthesis, and has broad prospects for development and utilization.
1.2 Domestic and foreign market conditions of isopropyl alcohol
The research and development of isopropyl alcohol in my country began in the early 1960s. In 1977, the Jinzhou Petrochemical Company Refinery (formerly Jinzhou Petroleum No. 6 Plant) was completed and put into operation. A 20,000 t/a propylene gas phase direct hydration method was used to produce isopropyl alcohol. The installation was expanded to 50,000 t/a in October 1992 and to 100,000 t/a in 1999. The No. 1 Refinery Plant of Lanzhou Refinery and Chemical Plant used the propylene indirect hydration method to build a 600 t/a production unit. However, it was discontinued in June 1994 due to backward technology, high production costs, and lack of market competitiveness. At the end of 2005, my country’s first industrial unit for the production of isopropyl alcohol through the direct hydration of medium-pressure propylene was successfully put into operation at Shandong Haike Chemical Industry Co., Ltd., with a production capacity of 30,000 t/a, and product quality reaching the national standard for premium products. This industrialized device uses a special catalyst for propylene hydration developed by Dalian Institute of Chemical Physics, Chinese Academy of Sciences and a process for direct hydration of propylene to isopropanol. In this technology, a special resin catalyst for propylene hydration is made of polystyrene. The temperature resistance of the resin is enhanced by introducing electron-withdrawing groups. The resin is synthesized through processes such as purification, sulfonation, anti-fragmentation, strength improvement, and activation of active groups. Warm type resin catalyst. The catalyst has excellent water resistance, high pressure resistance and crushing resistance, good low-temperature activity, less sulfonic acid loss, and the initial reaction temperature and reaction pressure are lower than similar foreign technologies. The process design package provided by Dalian Institute of Chemical Physics for the 30,000 t/a isopropanol unit of Haike Chemical Industry Company adopts a fixed bed process. According to the needs of the hydration reaction process, the propylene hydration conversion rate and reaction heat are controlled to make the hydration reaction bed The temperature distribution is uniform and the reaction bed pressure is reduced. It can be used with different concentrations of raw material propylene. The production process has no environmental pollution, achieves low energy consumption, and establishes a simpler and more efficient separation process. By the end of 2006, my country’s total production capacity of isopropanol reached approximately 140,000 t/a. In addition to PetroChina Jinzhou Petrochemical Company and Shandong Haike Chemical Industry Co., Ltd., there are also companies such as Shanghai Solvent Factory, Jinan Chemical Factory, Jinan Chemical Industry Co., Ltd. Manufacturers such as West Petroleum Factory No. 5, Shanghai People’s Pharmaceutical Factory, Beijing Chemical Reagent Research Institute, and Tianjin Experimental Factory No. 3 produce small amounts of isopropanol, with production capacities mostly around 1,000 t/a. In addition, there are some reagent manufacturers that produce isopropyl alcohol for use as chemical reagents and chromatographic analysis reagents. The largest production capacity is about 20 t/a, and the smallest is only 5 t/a. In order to meet domestic demand, PetroChina Jinzhou Petrochemical Company plans to invest 418 million yuan during the “Eleventh Five-Year Plan” period to use a combination of independent technology and new technologies to build a new 150,000 t/a isopropyl alcohol production unit to form a large-scale production unit. production, and will implement the co-production of isopropyl ether from isopropyl alcohol and develop multiple brands of isopropyl alcohol downstream products. By then, the company’s isopropyl alcohol production capacity will reach 250,000 t/a, making it the largest isopropyl alcohol manufacturer in Asia. It is expected that by 2008, my country’s total production capacity of isopropyl alcohol will reach approximately 300,000 t/a. With the continuous increase of production capacity, the output of isopropyl alcohol in my country is also increasing. In 1997, the output of isopropyl alcohol in my country was 49,200 tons. In 2003, the output reached 81,700 tons. In 2005, it reached 91,000 tons. In 2006, it reached 115,000 tons, a year-on-year increase of about 26.37%. The average annual increase in output from 2001 to 2006 The rate is approximately 11.41%.
As of the end of 2006, foreign production of isopropyl alcohol has developed steadily. The total production capacity of isopropyl alcohol in the world was 2.153 million t/a in 2002, which increased to 2.463 million t/a in 2006. The production capacity in North America was 1.050 million t/a, accounting for approximately 1.05 million t/a of the total production capacity of isopropyl alcohol in the world. 42.63% of the total; the production capacity of Asia is 632,000 t/a, accounting for approximately 25.66% of the total production capacity; the production capacity of Central and Eastern Europe is 74,000 t/a, accounting for approximately 3.0% of the total production capacity; Central and South America The production capacity of China is 57,000 t/a, accounting for approximately 2.3% of the total production capacity; the production capacity of Western Europe is 650,000 t/a, accounting for approximately 26.4% of the total production capacity. Among them, Shell Chemical Company is currently the world’s largest isopropyl alcohol manufacturer, with a production capacity of 794,000 t/a, accounting for approximately 32.2% of the world’s total isopropyl alcohol production capacity; followed by ExxonMobil Chemical Company, with a production capacity of 340,000 t/a, accounting for about 13.8% of the total production capacity; the third is Dow Chemical Company and Sasol Olefins & Surfactants, with production capacities of 280,000 t/a and 22.0 �There are three legal types. The gas phase direct hydration method is represented by the Viba method developed by the German Viba Company, the liquid phase direct hydration method is represented by the solution catalytic method of Japan’s Tokuyama Soda Company, and the gas-liquid mixed phase method is represented by the Deutche Texaco German branch of the United States. ) is represented by the ion exchange resin method.
2.2.1 Vapor phase direct hydration method (Viba method)
The Viba gas-phase direct hydration method is one of the main methods for producing isopropyl alcohol in the world. my country’s Jinzhou Petrochemical Company uses this method for production. This method uses phosphoric acid/diatomite as the catalyst. The mass fraction of phosphoric acid in the catalyst is 20%~30%. The saturated vapor pressure of phosphoric acid on the catalyst surface plays a major role during the reaction. Compared with the indirect hydration method, this method has good selectivity and less by-products. The total conversion rate of propylene reaches 97%, and the selectivity of producing isopropyl alcohol reaches 98%~99%. The corrosion and pollution problems of the equipment are greatly improved. At the same time, The process is short, the equipment is simple, and it can be used to produce ethanol after improvement. The disadvantage is that in order to prevent the dissolution of phosphoric acid, the direct hydration method needs to convert water into a gaseous state, so high-temperature and low-pressure reaction conditions that are unfavorable to the equilibrium are used, resulting in a low conversion rate, a large amount of unreacted propylene that needs to be recycled, and high energy consumption; In order to reduce the amount of by-products produced, the mass fraction of raw material propylene is required to be above 99%; phosphoric acid is constantly lost, so additional phosphoric acid needs to be added during production.
2.2.2 Liquid phase direct hydration method
The liquid-phase direct hydration method was successfully developed by Tokuyama Soda Company of Japan in the 1970s. This method uses an aqueous solution of tungsten polyanions (such as tungstosilicic acid) as the catalyst (pH=2~3), where the concentration of [Si(W 3 O 10) 4] in water is (1/4 000~1/100 ) mol/L. The advantage of this method is that the catalyst activity is high and propylene is actively complexed with polyanions. Compared with the commonly used hydration in acidic aqueous solutions such as sulfuric acid, the reaction speed increases by 2 to 3 times at the same hydrogen ion concentration; The single-pass conversion rate of propylene is high and the selectivity is high, which improves the problem of catalyst loss; the catalyst is relatively stable, recyclable, and has a long life; it is pollution-free. Although the reaction process requires high pressure, the equipment does not require special materials and has no corrosive problems. . The disadvantages are that it consumes a lot of electricity, the crude product contains a lot of water, and it consumes a lot of heat during distillation.
2.2.3 Gas-liquid miscible method
The gas-liquid miscible phase method is represented by the ion exchange resin method of Deutche Texaco, the German branch of the United States. Use active cation exchange resin as catalyst. Because the catalyst has good activity and water resistance, it can react at lower reaction temperatures and larger water-to-ene ratios. Compared with the Viba and Tokuyama Soda methods, there is no need for high-purity propylene and a large amount of unreacted propylene circulation. The reaction conditions are relatively mild, the propylene conversion rate is high, and the energy consumption is low. The disadvantages are that the catalyst is expensive and has a short life.
