Proprietary process technology CYCLOHEXANONE OXIME AMMOXINATION OF CYCLOHEXANONE WITH TITANIUM SILICATE (TS-1) PROPIETARY CATALYST Versalis proprietary process technologies available for licensing II 1 Our company Our commitment to excellence, in quality of our Versalis – the petrochemical subsidiary of Eni – is products and services, makes our company an active a dynamic player in its industry sector facing the partner for the growth of customers involved in multifold market needs through different skills. petrochemical business. With a history as European manufacturer with more Through engineering services, technical assistance, than 50 years of operating experience, Versalis stands marketing support and continuous innovation, our as a complete, reliable and now global supplier in the knowledge is the key strength to customize any new basic chemicals, intermediates, plastics and elastomers project throughout all phases. market with a widespread sales network. Customers can rely on this strong service-oriented Relying on continuous development in its production outlook and benefit from a product portfolio that plants as well as in its products, strengthening the strikes a perfect balance of processability and management of the knowledge gained through its long mechanical properties, performance and eco- industrial experience, Versalis has become a worldwide friendliness. licensor of its proprietary technologies and proprietary catalysts. The strong integration between R&D, Technology and Engineering departments, as well as a deep market expertise, are the key strengths for finding answers to customers requirements. Introduction to Versalis Titanium Silicalite (TS-1) Cyclohexanone Oxime process proprietary catalyst Versalis is in the position to offer the most advanced Versalis can always provide appropriate solutions to Titanium Silicalite (TS-1) catalyst, one of the most Wastes and emissions process and technology to produce Cyclohexanone different client’s needs thanks to its capabilities and important innovation in heterogeneous catalysis over The process produces very small amount of wastes; Oxime, the key intermediate for the production of experience in the following fields: the last decades, is a high performances composite waste water has low salt content; oil drains are low and Caprolactam and then of Nylon 6. The process material specifically designed for industrial oxidation discontinues. Solid wastes consist in small quantity of is based on the reaction of cyclohexanone and Research and operation reactions with hydrogen peroxide. TS-1 is the result spent catalyst to be washed with demineralised water ammonia in presence of dilute hydrogen peroxide as Versalis background and expertise comes from of long-term research within eni group associated and dumped at an adequate location. oxidizing agent (so-called ammoximation reaction) manufacturing experience and constant lab & pilot with direct Versalis’ experience in industrial oxidation Vent-gas from the units are sent to a proper waste and uses proprietary Titanium Silicalite catalyst (TS-1), plant testing. Since the early stages of development, reactions. gas treatment sections in order to lower all the plant a high performances composite material specifically our Cyclohexanone Oxime proprietary process emissions to a practically negligible amount. designed for industrial oxidation reactions. The technology has gained benefit from a deep The unique performances of the catalyst are due to ammoximation process is a straightforward one-step cooperation between leading scientists in the TS-1 the specific features of isolated Ti active sites, able to Industrial applications oxime production process wherein no hydroxylamine catalyst field and technicians involved in industrial efficiently promote activity and selectivity in oxidation A demonstration plant (12 KTA capacity) was built at 2 formation step is required and no ammonium sulphate production at Versalis (former EniChem). reactions with hydrogen peroxide. Versalis’ Porto Marghera site (former EniChem) and 3 is co-produced. started up in 1994. Process design The technology is now fully proven at industrial scale, Main features of the innovative Versalis Process design is flexible and able to face different with a 70 KTA capacity unit on stream since 2001 and Cyclohexanone Oxime process are: conditions and constraints. Any project is individually a 100 KTA capacity unit on stream since 2014, whose lower capital expenditure due to the elimination of evaluated to offer the best solution, tailored to specific produced cyclohexanone oxime has been feeding the hydroxylamine formation step; customers needs. Thermal and fluodynamic analysis since then to downstream Caprolactam units. elimination of the ammonium sulphate formation, (CFD) are extensively applied to the design of key Product quality still one heavy drawback in the traditional equipment such as ammoximation reactor, its feed technologies; distributors, agitator and filtering system. unrivalled level of plant safety due to the very mild Cyclohexanone Oxime (dry basis) 99.8% wt typical reaction conditions and proprietary reactor design; Mechanical design unique selectivity to Cyclohexanone Oxime in the Versalis Engineering Dept. has been working in close reaction stage, what it keeps easier the purification coordination with the Process Dept. since a long time. stages and lower the raw material and utilities This fact has allowed to develop unique and well Main process parameters consumption; sound engineering solutions for critical equipment, higher plant reliability and stability, as well as stable that guarantee the best results in terms of mechanical Material Balance MT per MT Cy-one Oxime cyclohexanone oxime quality over time, coupled reliability and process performances. with the high catalyst lifetime which makes Cyclohexanone (as 100%) 0.875 the catalyst cost negligible on the total cost of production; Ammonia (as 100%) 0.165 low environmental impact due to elimination of the ammonia burning step necessary for Hydrogen Peroxide (as 100%) 0.345 hydroxylamine production. Utilities Consumption MT per MT Cy-one Oxime Low pressure steam consumption 2.5 Process description Cyclohexanone, ammonia and hydrogen peroxide are agent to recover anhydrous raw oxime. Waste water, fed to the reactor where the ammoximation reaction with traces of toluene and oxime coming out from the takes place in presence of Titanium Silicalite (TS-1) bottom of the oxime extraction column, is sent to a proprietary catalyst and tertiary-butanol (TBA) as toluene stripping column where organic compounds solvent. are recovered from water. fig. 1 Waste water is then sent to an oxidative treatment The reaction takes place in liquid phase and is section where residual organics are oxidised in exothermic (some of the reaction heat is recovered to presence of hydrogen peroxide. Anhydrous raw oxime heat up reagents). with toluene is sent to oxime washing unit and then to The catalyst acts by form of solid microspheres the oxime/toluene distillation column. dispersed in the reaction media. The reactor is a refrigerated continuous stirred tank reactor (CSTR Toluene is recovered as top product of the oxime/ 4 reactor type) equipped with filters that allow the liquid toluene distillation column and is recycled back to Cyclohexanone recycle 5 reaction product to leave the reactor and retains the the oxime extraction column. A small portion of the solid catalyst inside. recycle toluene is sent to the toluene purification A discontinuous make-up of fresh catalyst takes place column in order to purge out some minor by-products. TBA + Ammonia recycle from the catalyst feed unit and an amount of spent Raw anhydrous oxime is recovered as bottom product catalyst is purged from the bottom of the reactor, in a from oxime/toluene distillation column and is sent to definite volume of slurry. Gas vent coming from the the cyclohexanone recovery column where pure oxime OFF-GAS NaOH ammoximation reactor is sent to a washing column is recovered as bottom product while unconverted TREATMENT Demi water Oxime Steam and then to a dedicated catalytic treatment section. cyclohexanone is recycled back to the reactor. washing unit Oxime product Oxime/toluene Cyclohexanone The liquid reactor effluent consists mainly of oxime, Process is provided with an adequate vent gas distillation column recovery column tertiary-butanol, water, unconverted cyclohexanone treatment section in order to lower all the plant Cyclohexanone and ammonia. The liquid reactor effluent is sent to emission to a practically negligible amount. Ammonia the TBA recovery column where TBA and ammonia Hydrogen Peroxide TBA make-up Oxime/water are recovered as top product and recycled back to the Process is also provided with a specific system of Catalyst make-up separator reactor. on-line analyzers and safety interlocks which provide, together with proprietary design of the reactors and Ammoximation TBA recovery The raw oxime product coming from the bottom of the unique performances of the TS-1 catalyst, an unrivalled Reactor column TBA recovery column is sent to a liquid-liquid oxime level of plant safety and reliability. extraction column where toluene is used as extracting Toulene make-up WASTE WATER TREATMENT By-products purge Oxime Toluene Toluene extraction stripping purification column column column Proprietary process technologies portfolio Biotech PROESA® 2G Ethanol and Cellulosic Sugars Phenol and derivatives Cumene (with PBE-1 zeolite based proprietary catalyst)*