Catalyst Suppliers

Semibatch hydrogenation of edible oils has a long history and a well-estabhshed body of prac tice by manufacturers and catalyst suppliers. Problems of new oils, new specifications, new catalyst poisons,... 

Alumina is the source for an active matrix. Most active matrices used in FCC catalysts are amorphous. However, some of the catalyst suppliers incorporate a form of alumina that also has a crystalline structure. 

At this state of the catalyst synthesis there are two approaches for further treamient of NaY. Depending on the particular catalyst and the catalyst supplier, further treatment (rare earth exchanged) of NaY can be accomplished either before or after its incorporation into the matrix. Post-treatment of the NaY zeolite is simpler, but may reduce ion exchange efficiency. 

With each shipment of fresh catalyst, the catalyst suppliers typically mail refiners an inspection report that contains data on the catalyst s physical and chemical properties. This data is valuable and should be monitored closely to ensure that the catalyst received meets the agreed specifications. A number of refiners independently analyze random samples of the fresh catalyst to confirm the reported properties. In addition, quarterly review of the fresh catalyst properties with the catalyst vendor will ensure that the control targets are being achieved. 

The reported surface area is the combined surface area of zeolite and matrix. In zeolite manufacturing, the measurement of the zeolite surface area is one of the procedures used by catalyst suppliers to control quality. The surface area is commonly determined by the amount of nitrogen adsorbed by the catalyst. 

The surface area correlates fairly well with the fresh catalyst activity. Upon request, catalyst suppliers can also report the zeolite surface area. This data is useful in that it is proportional to the zeolite content of the catalyst. 

Refiners send E-cat samples to catalyst manufacturers on a regular basis. As a service to the refiners, the catalyst suppliers provide analyses of the samples in a form similar to the one shown in Figure 3-12. Although the absolute E-cat results may differ from one vendor to another, the results are most useful as a trend indicator. 

The sodium in the E-cat is the sum of sodium added with the feed and sodium on the fresh catalyst. A number of catalyst suppliers report sodium as soda (Na20). Sodium deactivates the catalyst acid sites and causes collapse of the zeolite crystal structure. Sodium can also reduce the gasoline octane, as discussed earlier. 

Many available catalyst additives that can be used to meet a specific objective are listed in Table 6.2. These have become a necessary adjunct to FCC operations. Originally, catalyst suppliers tried to incorporate the function into the catalyst but a myriad of needs or the catalyst manufacturing scheme employed made a single all-encompassing catalyst formulation impossible. 

Selective Catalytic Reduction (SCR) has been commercially used since the mid 1980s on fired equipment with the hrst application on a boiler in 1976. The first SCR unit installed on a fluid catalytic cracking unit was at Saibu Oil Company in Yamaguchi, Japan in April 1986. Since then, nearly two dozen ECC units have installed SCR units to remove NO from the flue gas and more are slated to be built in the future. Vendors and catalyst suppliers of this technology include Haldor-Topsoe, Mitsubishi Power Systems, Hitachi, Technip, BASE, and Cormetech. 

New proposed Tier 2 emission standards proposed for introduction in the 2004 model year would apply to sport utility vehicles, minivans, and pickup trucks and make them meet the same standards as passenger cars. It has also been proposed to lower the sulfur level in gasoline to 30 PPM from the current average level of 300 PPM by 2004. The Euro IV limits proposed for 2005 are satisfied by technology from at least one catalyst supplier... 

To achieve maximum ammonia conversion, one catalyst supplier has developed a catalyst pack that consists of several types of gauze237 ... 

Statistical process control is being implemented by catalyst manufacturers to detect and eliminate, if possible, causes of variations in quality. As many departments, such as operating, technical, purchasing, and R D, become involved in the pursuit of quality, a unified approach toward the implementation of total quality is being developed through an accreditation procedure for catalyst suppliers. 

Petrochemical industries require many different types of catalysts and adsorbents in process applications. Major portions of such requirements are being met through purchases from commercial catalyst suppliers. The importance of catalysts to chemical and petrochemical industries cannot be overstated. Deviations in catalyst performance from expectations affect yields and feedstock utilization, generate undesirable side reactions and by-products, increase operating costs, and reduce capacity. The cost of such deviations from the expectations which were incorporated in the process design, are not always known and can easily exceed the cost of a new catalyst charge. 

Finally, this year, a standard catalyst supplier accreditation procedure is being implemented. Primary emphasis is on the implementation of control charts and statistical process control (SPC) procedures in the manufacture of commercial catalysts in order to improve lot to lot consistencies (3) for purchased catalysts. 

Our current views on how to implement a catalyst supplier accreditation procedure are as follows. A team consisting of representatives of technical, analytical, plant operation and purchasing functions visits with the supplier s equivalent representatives prior to placing a major order, or at certain intervals. The meeting will have the following five part agenda ... 

In working with catalyst suppliers ve are led to the understanding that SPC procedures and control charts can be applied to the preparation o smaller batches o finished catalysts such as used in chemical industries. 

ASTM Methods for catalyst and zeolite analyses and American and International Standards for quality control and quality assurance form the cornerstones of the foundation upon which future catalyst supplier-catalyst user relationships will be constructed. 

Dilute ethylene for chemical applications, such as styrene production, can be withdrawn downstream of the hydrogenation reactor. The ethylene content is typically 60 vol%. Catalyst suppliers have tested the hydrogenation step, and commercially available front-end catalysts are suitable for this application. 

Magnesium aluminate, the preferred support of one catalyst supplier, has a larger specific surface area. But this material must be calcined to a higher temperature during manufacture of the support particles to ensure it contains no free magnesium oxide, which would be hydrated to hydroxide at temperatures below 300 °C. This chemical change results in a volume increase, which would destroy the structure and impair the mechanical stability of the catalyst. 

In this type of converter only a fraction of the recycle gas enters the first catalyst layer at about 400 °C. The catalyst volume of the bed is chosen so that the gas leaves it at ca. 500 °C (catalyst suppliers specify a maximum catalyst temperature of 530 °C). Before it enters the next catalyst bed, the gas is quenched by injection of cooler (125-200 °C) recycle gas. The same is done in subsequent beds. In this way the reaction profile describes a zig-zag path around the maximum reaction rate line. A schematic drawing of a quench converter together with its temperature/location and temperature/ammonia concentration profiles is presented in Figure 86. 

Catalyst Type - Nickel metal catalyst, sometimes promoted with copper, aluminum oxide, or sulfur, are commonly used in commercial hydrogenation. These catalysts are prepared by a variety of techniques, some proprietary to the catalyst supplier, to provide the surface activity necessary for the desired selectivity. Precious metals have been found to be effective hydrogenation catalysts, which are more active at lower temperatures and produce less trans-isomers. However, their use has been deterred by the initial cost and recovery problems associated with the minute quantities required. 

In spite of all these possible deactivation mechanisms, longtime stable activity is always reported for SCR catalysts 16,000 and 24,000 hours of operation are typically guaranteed by catalyst suppliers for HD and TE systems, respectively, but even longer catalyst lives are observed in practice. Besides, economy is significantly influenced by optimized strategies for the addition of extra catalytic material and the replacement of spent catalyst. 

Copper chromite (Lazier catalyst). Supplier Harshaw (CU-0202P 556-002). For preparation of the catalysC an aqueous solution of barium nitrate and cupric nitrate trihydrate is stirred during addition of a solution of ammonium chromate, prepared from ammonium dichromate and aqueous ammonia. The reddish brown precipitate of copper barium ammonium chromate is washed and dried and decomposed by heating in a muffle furnace at 350-450 . The ignition residue is pulverized, washed with 10% acetic acid, dried, and ground to a fine black powder. 

Many new catalysts have entered the market particularly for resid upgrading, hydrocracking and middistillate deep desulfurization. The leading catalyst suppliers today, Criterion and Akzo Nobel, have been the most active companies with new catalysts for nearly all market segments. 

Catalysts suppliers as Johnson-Mattey (ref. 12), A.G. Degussa (ref. 13) or Heraeus provide special platinum on carbon catalysts at industrial scale. 

B.V., Catalysts and Chemical Division, PO Box 19, 3454 ZG De Meern, The Netherlands Heraeus, Chemical Catalysts, Postfach 1553, D-63450 Hanau 1, Germany Johnson Matthey, Process Catalysts, Orchard Road, Royston, Hertfordshire SG8 5HE, UK. They also have a substantial know-how about which type of catalyst is the most suitable for a specific problem. Our experience has shown that it is of advantage to search for or optimize a suitable catalyst in close collaboration with the catalyst suppliers. This is especially true for the development of technical processes and/or when the development team has little hydrogenation experience. Catalyst screening and development should always be performed with specified catalysts that can be supplied in technical quantities when needed. For laboratory use, Fluka and Aldrich Inorganics offer a wide variety of hydrogenation catalysts that are adequately suited for preparative purposes, although the catalyst manufacturer and the exact type of catalyst is not usually specified. 

Precious metal catalysts are usually shipped back to the catalyst suppliers to recover the expensive metal from the spent catalysts. For hygiene and regulatory reasons the spent catalyst must be washed thoroughly to remove toxic organic products. To get the best results for metal recovery, spent catalysts should not contain inorganic products (e. g. materials to facilitate filtration such as Tonsil or Hyflo) or large amounts of water. 

Catalysts available for hydrofinishing have improved substantially since the appearance of these publications, although the chemistry will be the same or very similar. Both license and catalyst suppliers should be interviewed thoroughly and pilot plant work undertaken where necessary to select the best tit for the specific needs of a particular refiner. 

The aim of catalyst development is to adjust the catalyst characteristics to the requirements set by the reaction conditions, reactor equipment, and available filtration units. Thus, a close collaboration between catalyst supplier and customer is required to assure optimum catalytic performance. 

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