Upbeat about Caprolactam    

Caprolactam (CPL) is mainly used to produce polyamide 6 fibers, resins and films, which have extensive applications in the textile, automotive, electronics and machinery sectors.
   Worldwide, caprolactam capacity was reportedly 4.65 million t/a in 2008 and increased to 4.754 million t/a in 2009 - growth of 2.24%. Total consumption in 2008 was 3.788 million tons.
   China started commercial production of caprolactam in the late 1950s. It was however only in the mid and late 1990s that three large production units in DSM Nanjing Chemical Company, Sinopec Baling Petrochemical Company Limited and Sinopec Shijiazhuang Chemical Fiber Company Limited were completed and put on stream. By the end of December 2009 China had four caprolactam producers with a combined capacity of 475 000 t/a. Except the 65 000 t/a unit in Sinopec Shijiazhuang Chemical Fiber Company Limited, which uses the toluene process, manufacturers use benzene as raw material. It is expected that China's total caprolactam capacity will at most reach around 675 000 t/a in 2012.
   Despite some increase of caprolactam output in China in recent years, the needs in the development of the chemical fiber sector and the plastic product sector still cannot be satisfied locally. China has to import great quantities each year. According to customs, China imported 377 thousand tons of caprolactam in 2003 and increased to 450 thousand tons in 2008; then, 601 thousand tons in 2009, an increase of 33% in just one year. While a net importer, China also exports small amounts.
   China mainly imports caprolactam from eight countries: the United States, Russia, Japan, Korea, Belarus, Poland, Mexico and Ukraine. The volume imported from these countries in 2008 was 379 400 tons, accounting for around 84.29% of domestic consumption. The imports from these eight countries in 2009 was 428 600 tons, an increase of around 12.97% over the previous year and accounting for around 71.28% of the total.
   With the rapid development of nylon fiber yarns, nylon cords, nylon engineering plastics, the demand for caprolactam in China has increased in recent years. Not counting the changes in inventory, China consumed 677 thousand tons of caprolactam in 2004 and more than 700 thousand tons in 2005. Hurt by the worldwide economic crisis, China's consumption of caprolactam went soft in 2008, being only 737 800 tons, a drop of 4.68% from the previous year. With the gradual improvement of the economy in China, the downstream demand became brisk, the output of caprolactam was increased and consumption surged drastically. China's apparent consumption of caprolactam reached 939.9 thousand tons in 2009, an increase of 27.39% over the previous year. The average annual growth of the apparent consumption was 6.78% between 2004 and 2009. The self-sufficiency rate of caprolactam was however reduced from 39.3% in 2008 to 36.2% in 2009.
   In China, caprolactam is mainly used to produce nylon 6 fiber and nylon 6 engineering plastics. The production proportion of nylon fiber in synthetic fibers already dropped from 20.0% in the late 1960s to 4.5% in 2008. China produced 1.0161 million tons of nylon fibers in 2008. Of total, the output of nylon 6 fibers was around 720 thousand tons, consuming around 605 thousand tons of caprolactam, accounting for around 82.0% of the total caprolactam consumption. China's nylon fiber sector will maintain a relatively rapid growth in the next few years and the demand in nylon cords will become a major driver for fiber-grade caprolactam. It is expected that the demand for caprolactam in nylon 6 fiber will reach around 750 thousand tons in 2012.
   In non-fiber sectors, nylon 6 is mainly used in domestic plastics (mainly palm yarns and fishing net yarns), engineering plastics (mainly castings for automobiles and electric appliances) and bi-oriented nylon films. The output of nylon 6 for non-fiber uses in China was around 110 thousand tons in 2008, consuming around 120 thousand tons of caprolactam. Moreover, China also needs to import considerable amounts of nylon films and castings. The demand for caprolactam in nylon 6 for non-fiber uses will grow fast through 2012. The demand growth of nylon 6 in engineering plastics will be the most evident. It is expected that the demand for caprolactam in nylon 6 for non-fiber uses will reach around 200 thousand tons in 2012. Along with the demand in other sectors, China's total demand for caprolactam will reach around 1 million tons in 2012. The country's capacity of caprolactam will be at most around 675 000 t/a at that time. Even if domestic caprolactam units make full-load production, there will still be a gap of around 325 thousand tons to be filled by import. Caprolactam, therefore, has a bright development and application prospect in China.
   Achievements in the research and development of new processes for the caprolactam production keep emerging worldwide. The commercial production today still mostly uses the benzene process. Upgrades for production are mainly concentrating on shortening the process route, simplifying the process flow, reducing the energy consumption, increasing the yield, reducing the generation of byproduct ammonium sulfate and minimizing pollution of the environment. In addition, efforts should also be made to use as little of precious metal catalysts and high alloy materials as possible.
   In terms of raw material supply, as China's three manufacturers use the phenol production process the supply of raw materials such as benzene, ammonia and sulfuric acid is basically adequate. C4 resources are quite rich in China and the development of the production process using butadiene as raw material can therefore also be considered at the optimal time. Once such process come into commercial production, the production of hexamethylene diamine can be combined with the production of caprolactam so as to make a full use of C4 resources.
   Chinese enterprises have already developed complete caprolactam technologies with intellectual property rights or modified technologies based on original processes. Sinopec Baling Petrochemical Co Ltd and Sinopec Research Institute of Petroleum Processing have jointly developed a new green combination process to make caprolactam, which can shorten the process route, reduce operational complexity and minimize environmental pollution, as well as greatly drive down production costs. The hexahydrobenzoic acid/cyclohexanone oxime process to make caprolactam, jointly developed by companies including Sinopec Shijiazhuang Chemical Fiber Co Ltd, also has a bright application prospect. The research institute of Sinopec Nanjing Chemical Industry Company has developed DHO21 catalysts for the production of cyclohexanone through cyclohexanol dehydrogenation and NCH1-1 platinum catalysts for the production of cyclohexane through benzene hydrogenation. Commercial production tests and commercial sideline tests have also been conducted on these two catalysts, showing that major property indexes of these catalysts have reached the advanced level of similar catalysts in developed countries. Chinese companies should accelerate the application of these new technologies or catalysts in commercial production units.
   Caprolactam downstream products such as nylon 6 fibers and nylon 6 engineering plastics have excellent application properties in both industrial and domestic uses and therefore have a bright application prospect. Safety nets, seat belts and case/bag fabrics produced by nylon 6 have huge development potential.