Purchased Catalysts

Quality assurance is an important consideration for the user and producer. Both aspects are discussed by Puls (17) in his symposium paper. Lot-to-lot variations in purchased catalyst can be minimized by a system of statistical process control by the catalyst producer, his supplier, and the user. The statistical process helps to minimize product quality variations by instituting corrective action on a real-time basis to prevent the production of off-specification material. 

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. 

Performance variations of different lots of the same brand of catalyst still are causes of significant plant problems in the industry. Such experiences justify efforts to develop effective quality control procedures for purchased catalysts. Obtaining a clear understanding of required catalyst properties is a first step. Plant problems and unusual events need to be recorded. The history of catalyst performance in the plant is most valuable to have in developing catalyst specifications. 

Specifications. Purchase specifications have to be defined first. Then, quality control of catalyst samples which are representative of the purchased catalyst lots, can be implemented to compare actual chemical and physical properties with the range of values stated in the purchase specifications. 

Information on purchased catalysts should include the lot numbers and dates of manufacture, and the amount of water and other volatile matter still contained on the catalyst. Specifications should provide data for chemical analyses, and physical-mechanical and physical-chemical properties. The latter information should include data concerning the average shape and sizes of particles, including oversized particles, fines content, and other measures of physical integrity. An example of information which could be included in purchase specifications for a fixed bed catalyst is shown in the following Table II. 

QC Experience. When we applied quality controls to purchased catalysts vithin Exxon Chemical Company, ve found... 

Catalyst User. Analysis of consecutive lots of purchased catalyst is usually a first step which customers can take to determine how catalyst properties oscillate between upper and lower specification values. This is illustrated in Figures 3 and 4. The two control charts shown contain the values of reduced nickel content of consecutive lots of similar nickel catalysts. Both catalysts contain about 50 wt % NiO and are prereduced. 

Conventional quality control procedures fall short of current needs to improve the consistency of purchased catalyst quality and are being supplemented by the use of control charts and statistical process control. 

METHOD 8 Check this outi This uses benzene or 1,3-benzodioxole (forX) as the starting material [24]. This method is better suited for speed makers because the AICI3 catalyst can tear up that methylenedioxy ring structure of the X molecule precursor. Chloroacetone can be easily purchased. 

A newer and equally effective way of swapping azides with halides (bromines or iodines) is in the use of phase transfer catalysts [68]. Strike wouldn t expect an underground chemist to purchase the exotic catalyst Aliquat 336 which the investigators in this reference used to get yields approaching 100% but an alternative catalyst of... 

This catalyst should really be purchased rather than made because its use in underground chemistry is limited and is hardly watched at all if not ever. This may change considering its potential as a precursor to the NaBHsCN in Strike s 1 method of choice. There are a lot of ways to make this catalyst, but the least involved is the one using boron trifluoride. What the method calls for is an apparatus called an autoclave. You know how using a vacuum causes the absence of pressure to make things boil at a lower temperature Well, an autoclave is a device that causes an... 

This catalyst has not been given a fair shake in underground literature and, as of this book s printing, is still relatively safe to purchase, A prudent chemist will most likely stock up on this chemical because the eventuality of more intense scrutiny is inevitable. The best way to make this product is to start with NaBH4 which is much more safe to buy. However, the way to go about making this catalyst is not very safe unless strict adherence to safety is used. 

Alcoholysis (ester interchange) is performed at atmospheric pressure near the boiling point of methanol in carbon steel equipment. Sodium methoxide [124-41 -4] CH ONa, the catalyst, can be prepared in the same reactor by reaction of methanol and metallic sodium, or it can be purchased in methanol solution. Usage is approximately 0.3—1.0 wt % of the triglyceride. 

The chemical complex includes the methanol plant, methyl acetate plant, and acetic anhydride plant. The methanol plant uses the Lurgi process for hydrogenation of CO over a copper-based catalyst. The plant is capable of producing 165,000 t/yr of methanol. The methyl acetate plant converts this methanol, purchased methanol, and recovered acetic acid from other Eastman processes into approximately 440,000 t/yr of methyl acetate. 

The advent of a large international trade in methanol as a chemical feedstock has prompted additional purchase specifications, depending on the end user. Chlorides, which would be potential contaminants from seawater during ocean transport, are common downstream catalyst poisons likely to be excluded. Limitations on iron and sulfur can similarly be expected. Some users are sensitive to specific by-products for a variety of reasons. Eor example, alkaline compounds neutralize MTBE catalysts, and ethanol causes objectionable propionic acid formation in the carbonylation of methanol to acetic acid. Very high purity methanol is available from reagent vendors for small-scale electronic and pharmaceutical appHcations. 

Ex situ or off-site, regeneration of noble metal catalysts is not commonly practiced by commercial petroleum refiners because it requires either an extended period with the process shut down or requires that a spare load of cosdy catalyst, which would only be used for a fraction of the time, be purchased and kept available. 

Raw material costs should be estimated by direct computation from flow rates and material prices. The flow rates are deterrnined from flow sheet material balances. The unit prices are obtained from vendors, company purchasing departments, or the Chemical Marketing Reporter. For captive raw materials produced internally, a suitable transfer price must be estabHshed. Initial catalyst charges can be treated as a start-up expense, working capital component, or depreciable capital, depending on the expected catalyst life and cost. Makeup catalyst is frequendy treated as a raw material. 

Feedstocks. A separate breakdown between fuels and feedstocks (qv) for the chemical industry (2) shows that the quantity of hydrocarbons (qv) used direcdy for feedstock is about as great as that used for fuel (see Fuels, synthetic Gasoline and other motor fuels). Much of this feedstock is oxidized accompanied by the release of heat, and in many processes, by-product energy from feedstock oxidation dominates purchased fuel and electricity. A classic example is the manufacture of nitric acid (qv) [7697-37-2] HNO. Ammonia (qv) [7664-41-7] burned in air on a catalyst at a pressure... 

In addition to the fixed capital investment needed to purchase and install process equipment and auxiliaries, there is a continuous expenditure referred to as operating cost, which is needed to operate the process. The operating cost (or manufacturing cost or production cost) includes raw materials, mass-separating agents, utilities (fuel, electricity, steam, water, refrigerants, air, etc.), catalysts, additives, labor, and maintenance. The total annualized cost of a process is defined as follows ... 

The purchase price of an initial charge of catalyst is but one factor entering into the cost of using a catalyst. For noble-metal catalysts, which have high reclaim value, this price is in itself relatively unimportant. The number of greater significance is the cost of the catalyst in use, that is, the cost of the catalyst when the value of reclaimed metal has been deducted,... 

Consideration of factory operation adds further advantages for the steady catalyst. The changing of the charge is often an expensive job and sometimes an unpleasant one, perhaps involving drilling out. It may also require the purchase of a separate reactor body so that a complete filled spare unit is always available. The extra capital inventory can be substantial. The... 

W-2 Raney nickel was purchased from W. R. Grace and Co. Prior to use it was washed with distilled water until neutral and then three times with absolute ethanol.4 This material may ignite spontaneously if allowed to become dry. Thus in decanting, a small amount of solvent must be left behind to cover the catalyst. Spent catalyst is discarded by slurrying in water and flushing the slurry down the drain with running water. 

A zeolite catalyst operated at 1 atm and 325-500 K is so active that the reaction approaches equilibrium. Suppose that stack gas having the equilibrium composition calculated in Example 7.17 is cooled to 500 K. Ignore any reactions involving CO and CO2. Assume the power plant burns methane to produce electric power with an overall efficiency of 70%. How much ammonia is required per kilowatt-hour (kWh) in order to reduce NO , emissions by a factor of 10, and how much will the purchased ammonia add to the cost of electricity. Obtain the cost of tank car quantities of anhydrous ammonia from the Chemical Market Reporter or from the web. 

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