Introduction to Adipic Acid

1. Chemical properties of adipic acid

Introduction to adipic acid

Alias: fatty acid
English name: adipic acid; Hexaneionic acid
Abbreviation: AA Structural formula: HOOC (CH2) 4COOH Molecular formula: C7H10O4 Properties: White crystal with a burnt bone odor. Melting point 153 ℃. Boiling point 332.7 ℃ (decomposition at 101kPa). Relative density (D425) 1.360. Flash point (open cup) 209.85 ℃. Ignition point (open cup) 231.85 ℃. Melting viscosity 4.54mPa • s (160 ℃). Slightly soluble in water, easily soluble in most organic solvents such as alcohol and ether. The moisture content should be below 0.40%, and the nitric acid content should be below 50.0 × 10-6. two Production process of adipic acid: Benzene method involves catalytic hydrogenation of refined benzene to produce cyclohexane, which is then oxidized to produce KA oil (a mixture of cyclohexanone and cyclohexanol, and then oxidized with nitric acid to produce adipic acid). In addition to refined benzene, this process also involves hydrogen, nitric acid (liquid ammonia), and other raw materials. The process flow is long, the one-time capital investment is large, there are many by-products, and there is industrial waste pollution, especially NO2 gas. Its greenhouse effect is more than 300 times that of CO2, and the product yield is not high. However, this process is mature and widely used in industry. At present, the total global production capacity of adipic acid using the benzene method is 2.38 million tons per year, accounting for 88.2% of the total production capacity. In recent years, researchers have developed a new method for producing adipic acid based on the original benzene method: using a special catalyst to partially hydrogenate benzene to produce cyclohexene, cyclohexene hydrates to produce cyclohexanol, and then oxidizes with nitric acid to produce adipic acid. This method consumes less hydrogen during the production of cyclohexanol, with cyclohexane as a byproduct. The process of generating cyclohexanol is almost free of three waste pollution, resulting in good product quality, high yield, and relatively low production costs. At present, both Japan's Asahi Kasei and China's Shenma Group use this method to produce adipic acid, with a total scale of about 170000 tons per year, accounting for 6.3% of the global total production capacity.
Phenol hydrogenation produces cyclohexanol, which is then oxidized with nitric acid to produce adipic acid. The equipment investment and production complexity of this method are not much different from those of the benzene method, making it suitable for areas with relatively abundant phenol raw materials. This method is only used in 5 factories in Hopewell, USA, Paulinia, Brazil, Zandvoorde, Belgium, Zeitz, Germany, and Novara, Italy, with a total scale of approximately 150000 tons per year, accounting for 5.5% of the global total production capacity.
The green synthesis of succinic acid is obtained by directly oxidizing cyclohexene with hydrogen peroxide under the catalysis of sodium tungstate.
The two-step carbonylation method of butadiene uses butadiene and carbon monoxide as raw materials. Firstly, butadiene is converted into methyl 3-pentenoate, then carbonylation is carried out to produce dimethyl adipate, and finally hydrolysis is carried out to obtain it.
The use of biomass glucose to produce succinic acid is a green production process and a safer and cleaner way of succinic acid production. This new process is the most ideal. three Application: The primary use is as a raw material for nylon 66 (a condensation product of adipic acid and adipic acid) and engineering plastics. Polyamide 66 fiber is made by condensation of adipic acid containing 6 carbon atoms. Secondly, it is used for the production of various ester products, as plasticizers and advanced lubricants. In addition, adipic acid is also used as a raw material for polyester polyols and as an acidifying agent for various foods and beverages, sometimes surpassing citric acid and tartaric acid. Adipic acid is also a raw material for pharmaceuticals, yeast purification, insecticides, adhesives, synthetic leather, synthetic dyes, and fragrances. four Domestic and international market situation
Production capacity: According to TecnonOrbiChem's forecast in London, the global demand for adipic acid in 2003 was 2.27 million tons, with 44% of it being nylon 6,6 fiber according to its use; Nylon-6,6 resin 25%; Polyols account for 18%; Plasticizer 4.5%; The rest is 8.5%. And the actual production capacity can reach 2.8 million tons per year, of which DuPont Company accounts for 39%; Rhodia17%； Solutia14%； BASF 9%; AsahiKasei6%； RadiciChimica5%， The other 10%. The distribution by country/region is: 1.002 million tons/year in the United States; 170000 tons per year in Canada; Brazil 80000 tons/year; 320000 tons/year in France; Germany has a production capacity of 408000 tons per year; 70000 tons/year in Italy; 56000 tons/year in Ukraine; 220000 tons/year in the UK (planned capacity expansion to 270000 tons/year); 127000 tons/year in China (planned expansion and new construction capacity to 330000 tons/year); 122000 tons/year in Japan; 135000 tons/year in South Korea; New

Add slope 114000 tons/year. Outlook: In the past two years, due to overcapacity and rising raw material prices, the gross profit of adipic acid producers has not been high. Due to the shift in the balance of supply and demand, the price of finished adipic acid began to rise since the second quarter of 2002, and the cost of raw materials was relatively low, resulting in considerable profits for producers.
According to analysis by TecnonOrbiChem in London, there is currently a global overcapacity in adipic acid production, with an operating rate of approximately 85%. Due to limited new production capacity in the coming years, the operating rate will continue to rise. It is expected that the global demand for adipic acid will continue to grow at a rate of 2% per year in the next 5 years, mainly due to the strong demand for nylon-6,6 engineering plastic resin. In the composition of adipic acid demand, the demand for nylon-6,6 accounts for about 70%, with an expected average growth rate of 1.7% per year in the future. Among them, the growth rate of nylon-6,6 for fibers is 1% per year, while the growth rate of nylon-6,6 for engineering plastics is 4.5% per year. The fastest growing demand is for polyols used in the production of polyurethane, with an expected growth rate of 4% to 5% per year, while the plasticizer market has a relatively small growth rate of about 1% per year.
Adipic acid is an important basic chemical product and one of the main raw materials for producing nylon and polyurethane. At present, the global production capacity of adipic acid has reached 2.7 million tons per year. China's adipic acid industry started relatively late, but has developed rapidly. In 2002, its production capacity exceeded 120000 tons per year, and the market consumption was about 195000 tons. Production is mainly concentrated in the United States and Europe. Currently, the global adipic acid production facilities are mainly distributed in North America and Western Europe, accounting for more than 80% of the global total production capacity. The major global manufacturers include DuPont, Shounuo, Monsanto, BASF, Asahi Kasei, Radisi, and Liaohua Rivneazot、 Companies such as Shenma and Bayer, among which DuPont's production capacity accounts for about 45% of the global total capacity, plus Shounuo, Monsanto, and BASF, the total production capacity of these four companies accounts for more than 80% of the global total capacity. The largest consumer area of adipic acid worldwide is the synthesis of nylon 66 (produced by the reaction of adipic acid and hexamethylenediamine to form nylon 66 salt, which is synthesized from adipic acid in some factories). Its consumption accounts for about 73% of the total global adipic acid production, of which nylon fiber accounts for 47% and nylon resin accounts for 26%. Non nylon consumption accounts for 27%, with polyurethane being the largest user in this field, while others include plasticizers, resins, coatings, and nylon 46. At present, the global adipic acid consumption market is showing an overall growth trend. Although there was a severe decline in global demand for adipic acid in the third quarter of 2001, it showed a rapid growth trend in 2002, with an increase of 4.0% -4.5%. Among them, the non nylon sector has the strongest growth, with an increase of over 7%, while the fiber sector has an increase of about 2% -2.5%. It is expected that the global consumption growth of adipic acid in 2003 will exceed that of 2002, especially in the non nylon field.

The adipic acid market in China is exceptionally active. The production of adipic acid in China is mainly concentrated in three enterprises: Shenma (50000 t/a), Liaohua (70000 t/a), and Taiyuan Chemical Plant. The rest are smaller scale enterprises.

The two major enterprises each have their own development priorities. As both Liaohua and Shenma start with the production of nylon 66, they have relatively complete nylon 66 production lines, high levels of technology and equipment, and good quality of adipic acid products. At present, Liaohua Company has increased the proportion of its commodity adipic acid and seized the opportunity of the rapid development of China's polyurethane industry to rapidly expand the production scale of adipic acid. Its expansion project is currently underway. Shenma, relying on the nylon 66 production technology introduced in the 1990s, continuously digested and absorbed it, gradually expanded its production scale, and on the basis of meeting its own needs, put the abundant adipic acid into the market to meet China's demand.

The market price is greatly influenced by foreign countries. The characteristics of China's adipic acid consumption market are slightly different from those of foreign countries, mainly concentrated in the fields of polyurethane and nylon. In 2002, the total demand for adipic acid in China was about 195000 tons, of which China produced about 100000 tons and imported 95000 tons. Among them, nylon products consumed about 65000 tons of adipic acid, accounting for 34.2% of China's total consumption, while the rest were non nylon products, accounting for 65.8% of the total consumption. In the non nylon field, the polyurethane industry has an absolute majority of demand for adipic acid, accounting for approximately 63.2% of the total.

In recent years, China's polyurethane industry has maintained a high growth rate (with an average annual increase of over 10%), and the demand for adipic acid has also increased synchronously. It is difficult for China's adipic acid production to meet the growth of market demand, and product imports have become very active. In 2002, the import volume of adipic acid in China reached 95000 tons, and it is expected to reach 120000 tons in 2003. The import situation in recent years is shown in Table 1. Previously, China's imports of adipic acid mainly came from South Korea, Japan, Singapore, Germany, Ukraine, and the United States.

Table 1 Recent Imports of Adipic Acid in China

Year

1999

2000

2001

200 2003 (January May)

2

Import Volume

14405

45325

70110

945

50520

85

The main factors affecting the price of adipic acid in China are supply relations and raw material prices. Due to the fact that the majority of China's adipic acid market relies on imports, the supply situation has become an important factor affecting the price of adipic acid in China (of course, this also conforms to market rules). The price of adipic acid abroad is mainly limited by the prices of raw materials (mainly petroleum benzene and fuel). As long as the global crude oil price remains relatively stable, the international price of adipic acid generally does not change significantly. The import of adipic acid in China is mainly concentrated in more than a dozen import and export traders and a few bulk users, making it difficult to form a monopoly. The sales price of adipic acid production enterprises in China is basically based on the import level, slightly lower than the import price. The price of refined benzene has a certain impact on the price of adipic acid in China, but it is not as severe as the impact of crude oil (petroleum benzene) prices on adipic acid prices in the international market. When the prices of crude oil and refined benzene are generally high in China/abroad, the price of adipic acid in China is more affected by raw materials. If only the price of refined benzene in our country rises, the price of adipic acid generally will not change significantly, and adipic acid production enterprises will reduce profits to absorb the cost of raw material price increases.
From the beginning of the second quarter to the end of the third quarter each year, which is the peak season for the polyurethane industry, the price of adipic acid will be higher to varying degrees, and then lower during the off-season, showing a more regular wave pattern. From the second half of 2001 to the first quarter of 2002, the price of adipic acid was at its lowest point, then rose to 9500 yuan/t and fluctuated around 9000-10000 yuan/t. Overall, as long as there is no major change in the international crude oil landscape, there will not be a significant upward trend in the price of adipic acid in China. It will remain at the current level and slightly decline with the decrease in international crude oil prices, depending on the situation of the crude oil. Generally, the decline will not be less than 9000 yuan/t (import). five Cost analysis:
Adipic acid consumption is as follows (calculated at the advanced level in China)

Adipic acid unit product material consumption, energy consumption, and cost

Name cyclohexanol

Unit kg/ton product

Price 14000

Consumption 0.778

Cost 10892

Total 13647.48

Nitric acid


kg/ton product

2000

0.96

1920

Electricity


kg/ton product

0.5

0.1564

0.0782

Steam

Ton/ton product

100

3.79

379

Water

Ton/ton product

1

175.7


Comprehensive energy consumption

kg of standard coal/ton

500

0.5614

280.7
Currently The market price of adipic acid is 15500 yuan. six With the booming development of the domestic automotive, textile, and polyurethane industries, the demand for adipic acid in China has been rapidly increasing at a rate of over 20% in recent years. In 2003, the total demand for AA in China was around 190000 tons, and it is expected to reach 230000 tons in 2004. The continuous expansion of AA demand has also attracted investment enthusiasm from some chemical enterprises. As the largest AA manufacturer in China, Liaoyang Petrochemical will expand a 70000 ton annual production unit in September this year, doubling its total annual production capacity to 140000 tons. In addition, Taiyuan Chemical also plans to expand its annual production capacity from 3000 tons to 50000 tons, and the specific timetable has not yet been announced to the outside world.
In addition to the two capacity expansion projects mentioned above, there are also rumors in the market that several chemical companies are interested in investing in AA projects, such as Xinjiang Dushanzi Chemical Group's intention to build a 70000 ton AA plant; Maoming Petrochemical Group intends to build a 100000 ton nylon 66 and 10000 ton AA project; Tianjin Petrochemical intends to construct supporting projects such as 120000 tons of CPL and 40000 tons of AA.
At present, these projects are still in the stage of attracting investment and have not been officially approved. However, industry insiders still have concerns that after the expansion of Liaohua, the proportion of domestic products in the domestic AA market will shift from the current nearly half to a dominant position. Continuing to invest in the AA project may lead to overcapacity and face fierce market competition. On the other hand, the production processes of AA are mainly benzene and phenol methods, and the raw materials required for preparation include hydrogen and liquid ammonia in addition to pure benzene and phenol. The production of AA has problems such as a long process flow, many by-products, heavy pollution of three wastes, and large one-time investment. So investment in AA should still be considered comprehensively based on factors such as the company's resources, region, and market, to avoid blindly following up.