Carbonate systems, proprietary

Several proprietary processes have been developed based on the hot carbonate system with an activator or catalyst. These activators increase the performance of the hot PC system by increasing the reaction rates both in the absorber and the stripper. In general, these processes also... 

The final step in the process involves reacting purified carbon monoxide from the gas separation plant with methyl acetate to form acetic anhydride, using a proprietary catalyst system and process. Part of the acetic anhydride is reacted with methanol to produce acetic acid and methyl acetate, and the latter is recirculated to the carbonylation step. 

HS A family of gas purification processes developed by Union Carbide Corporation, based on the use of proprietary solvents known as UCARSOLs. UCARSOL HS-101, is based on methyl diethanolamine and is used for removing hydrogen sulfide and carbon dioxide from other gases. Ucarsol LH-101 is used in its Cansolv system for flue-gas desulfurization. 

CATOX unit. Organic vapors and carbon monoxide are destroyed in the CATOX unit of each system using a proprietary precious metal catalyst developed by Engelhard Corporation. The operating range of the catalyst is from 500 to 1,000°F. For maximum destruction efficiency (99 percent) for organic compounds, the catalyst should operate at 900°F. 

This was ascribed to the short residence times applied (50-100 ms). Under these conditions, assuming the reaction mechanism proposed by Takahashi et al. shown above, carbon monoxide could only be formed by the reverse water-gas shift reaction, which is known to be slower than the reforming reaction. This is the case especially for catalyst systems with low activity towards water-gas shift. Holladay et al. [19] compared the performance of the same proprietary catalyst with that of a Cu/Zn catalyst which produced a higher carbon monoxide concentration of 3.1% in the reformate. 

The experiments were carried out at ambient pressure. All hydrocarbons were tested at a S/C ratio of three and all alcohols at a corresponding oxygen to carbon ratio. Decreasing conversion was found for the various fuels with increasing feed rates except for methanol owing to the very high reaction temperature of 725 °C. Table 2.9 summarizes some of the results presented for the various fuels. The proprietary catalyst showed only minor deactivation after 70 h TOS. It was deactivated reversibly by sulfur. Load changes of the liquid input from 100 to 10% resulted in a system response after 5-10 s. 

The initial corrosion control system used in a crude unit is a desalter. Modern desalters separate oil and water electrostatically. The internals used to accomplish electrostatic separation are normally of a proprietary design. The vessel itself is usually carbon steel. The bottom is often cement lined to protect it from salt water corrosion. The payout on a desalter is difficult to establish. Desalters are normally used when the salt content of the crude exceeds 20 lb per 1,000 barrels (ptb). When high reliability of the unit is desired, crudes with salt contents of 8 to 10 ptb are desalted. When desalting is used, the target is 1 ptb or less. Fluctuations in salt content are particularly troublesome to the downstream equipment therefore, the desalter should be designed for the maximum anticipated salt content. 

The equipment consists of a feed system, the reactor section, a GC, and an MS for product analysis. A Rupprecht and Patashnick TEOM 1500 PMA (Pulse Mass Analyzer) was used in the experimental design shown in Fig. 2. The tapered element with the catalyst bed on its end oscillates in a clamped-free mode. This is accomplished through a sensitive feedback amplifier control circuit connected to a mechanical drive to supply the necessary energy. The reactor tube is constructed of proprietary glass ( engineered glass ) (5). The reactor material has proved to be sufficiently inert for a number of applications. The catalyst bed is held in place by quartz, a-alumina, or carbon wool, depending on the conditions, and a metal cap. 

There are many proprietary coating systems to enhance the (oxygen and carbon dioxide) barrier properties of PET and these are generally added downstream of the PET manufacturing process and as such the product stewardship aspects of their use do not concern PET manufacturers. However, they are of concern to the conversion industry. As with scavengers, the majority of the systems in use today are commercially available and manufacturers should have already obtained regulatory approval for use in any particular country. It is very important that these approvals are carefully checked before putting materials on the market. 

Exxon Chemical Process. The Exxon Chemical process [1092], [1093] was specifically designed for the company s own site in Canada and so far not built for third parties. It uses a proprietary bottom-fired primary reformer furnace and a proprietary hot potash carbon dioxide removal system with a sterically hindered amine activator. Synthesis loop and converter are licensed by Haldor Topsoe A/S. Synthesis is carried out at 140 bar in a Topsoe S-200 converter and total energy consumption is reported to be 29 GJ/t NH3. 

Fluor Process. The Fluor process [280], [934], [940], [1094] uses the proprietary propylene carbonate based C02 removal system with adsorption refrigeration using low level heat downstream of the low-temperature shift. Methanation and C02 removal are placed between the compression stages and thus operate at higher pressure. With a value of 32 GJ/t NH3 [934] this is not really a low-energy concept. 

Lithium, whose proprietary names include Eskalith, Lithane, Lithonate, and others, is administered as lithium carbonate and used for treatment of the manic phase of affective disorders, mania, and manic-depressive illness. It is postulated to act by enhancing reuptake of catecholamines, thereby reducing their concentration in the neuronal junction. This produces a sedating effect on the central nervous system. Lithium also modulates the distribution of sodium, calcium, and magnesium in nerve cells, which reduces the rate of glucose metabolism that effects nerve function. The actual mechanism of action of lithium in affecting mania remains theoretical. 

Solvent-drying. After annealing at lOO C, the absorbed water inside the membranes was removed by a proprietary procedure. Its effect on gas permeation is given in Table VI. No effect is observed on the.helium and carbon dioxide permeability rates. But the permeability rates of nitrogen and methane are considerably lowered so that the separations of both systems, helium/nltrogen and carbon dloxlde/methane, are enhanced. With a value of 44.1 for helium/ nitrogen, the ideal separation factor of the external reference membrane is slightly exceeded, whereas the separation factor for CO2/CK of more than 2500 is Improved by a factor of 600. 

A proprietary dry noncryogenic adsorption system has been developed by Air Products and Chemicals, Inc. for recovery of carbon monoxide from syngas and offgas streams. The process preferentially separates carbon... 

Conductive organic coatings consist of a conductive carbon pigment in an organic binder. The most widely used systems have been solvent based. There are also water-based systems which have been developed more recently. One proprietary system uses a nickel coated carbon fibre rather than flaked graphite. 

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