For carbon dioxide

The reaction between CaiOH), + COj to produce sparingly soluble CaCOj is the common test for carbon dioxide. 

This reaction is used as a test for carbon dioxide. Passage of an excess of carbon dioxide produces the soluble hydrogencarbonate ... 

Fig. 4.20 DR plots for carbon dioxide adsorbed at 293 K on Linde molecular sieves. O, powder SA , powder 4A. (Reduced from the original diagram of Lamond and Marsh. )...

The deterrnination of impurities in the hehum-group gases is also accompHshed by physical analytical methods and by conventional techniques for measuring the impurity in question (93), eg, galvanic sensors for oxygen, nondispersive infrared analysis for carbon dioxide, and electrolytic hygrometers for water. 

Quicklime and hydrated lime are reasonably stable compounds but not nearly as stable as their limestone antecedents. Chemically, quicklime is stable at any temperature, but it is extremely vulnerable to moisture. Even moisture in the air produces a destabilizing effect by air-slaking it into a hydrate. As a result, an active high calcium quicklime is a strong desiccant (qv). Probably hydrate is more stable than quicklime. Certainly hydrated lime is less perishable chemically because water does not alter its chemical composition. However, its strong affinity for carbon dioxide causes recarbonation. Dolomitic quicklime is less sensitive to slaking than high calcium quicklime, and dead-burned forms are completely stable under moisture-saturated conditions. 

Anhydrous lithium hydroxide [1310-65-2], LiOH, is obtained by heating the monohydrate above 100°C. The salt melts at 462°C. Anhydrous lithium hydroxide is an extremely efficient absorbent for carbon dioxide (qv). The porous stmcture of the salt allows complete conversion to the carbonate with no efficiency loss in the absorption process. Thus LiOH has an important role in the removal of carbon dioxide from enclosed breathing areas such as on submarines or space vehicles. About 750 g of lithium hydroxide is required to absorb the carbon dioxide produced by an individual in a day. 

Capital costs which foUow the same trend as energy consumption, can be about 1.5 to 2.0 times for partial oxidation and coal gasification, respectively, that for natural gas reforming (41). A naphtha reforming plant would cost about 15—20% more than one based on natural gas because of the requirement for hydrotreatiag faciUties and a larger front-end needed for carbon dioxide removal. 

To prevent contact with oxygen, the beer in the pressure tanks is exposed only to a carbon dioxide atmosphere. The pressure must be higher than the saturation pressure for carbon dioxide. Infection in the brewery is prevented by daily cleaning and disinfection of all equipment in contact with the beer. In the past, almost all the beer left the brewery in kegs, but today most beer is bottled or caimed. The ratio is different from country to country. The growing share of beer in bottles or cans has provided a great need for filling machines with capacities of up to 100,000 bottles or cans per hour. 

Carbon dioxide used in carbonated beverages must be food-grade and must meet the Compressed Gas Association commodity specifications for carbon dioxide. In addition, carbon dioxide is tested for purity, taste, and odor before being used in the production of beverages. 

Available data on the thermodynamic and transport properties of carbon dioxide have been reviewed and tables compiled giving specific volume, enthalpy, and entropy values for carbon dioxide at temperatures from 255 K to 1088 K and at pressures from atmospheric to 27,600 kPa (4,000 psia). Diagrams of compressibiHty factor, specific heat at constant pressure, specific heat at constant volume, specific heat ratio, velocity of sound in carbon dioxide, viscosity, and thermal conductivity have also been prepared (5). 

Equations for viscosity at different temperatures, pressures, and thermal conductivity have also been provided (5). The vapor pressure function for carbon dioxide in terms of reduced temperatures and pressure is as foUows ... 

Diagrams of isobaric heat capacity (C and thermal conductivity for carbon dioxide covering pressures from 0 to 13,800 kPa (0—2,000 psi) and 311 to 1088 K have been prepared. Viscosities at pressures of 100—10,000 kPa (1—100 atm) and temperatures from 311 to 1088 K have been plotted (9). 

SolubiHty of carbon dioxide in ethanolamines is affected by temperature, amine solution strength, and carbon dioxide partial pressure. Information on the performance of amines is available in the Hterature and from amine manufacturers. Values for the solubiHty of carbon dioxide and hydrogen sulfide mixtures in monoethanolamine and for the solubiHty of carbon dioxide in diethanolamine are given (36,37). SolubiHty of carbon dioxide in monoethanolamine is provided (38). The effects of catalysts have been studied to improve the activity of amines and provide absorption data for carbon dioxide in both mono- and diethanolamine solutions with and without sodium arsenite as a catalyst (39). Absorption kinetics over a range of contact times for carbon dioxide in monoethanolamine have also been investigated (40). 

Approximate Inversion-Curve Locus for Carbon Dioxide. ... 

Experience in air separation plant operations and other ciyogenic processing plants has shown that local freeze-out of impurities such as carbon dioxide can occur at concentrations well below the solubihty limit. For this reason, the carbon dioxide content of the feed gas sub-jec t to the minimum operating temperature is usually kept below 50 ppm. The amine process and the molecular sieve adsorption process are the most widely used methods for carbon dioxide removal. The amine process involves adsorption of the impurity by a lean aqueous organic amine solution. With sufficient amine recirculation rate, the carbon dioxide in the treated gas can be reduced to less than 25 ppm. Oxygen is removed by a catalytic reaction with hydrogen to form water. 

A comparison of experimental data for carbon dioxide absorption obtained oy Hatta anci Katori (op. cit.), Grimley [Trans. Inst. Chem. Eng., 23, 228 (1945)], and Vyazov [Zh. Tekh. Fiz. (U.S.S.R.), 10, 1519 (1940)] and for absorption or oxygen and hydrogen by Hodgson (S. M. thesis, Massachusetts Institute of Technology, 1949), Henley (B.S. thesis. University of Delaware, 1949), Miller (B.S. thesis. University of Delaware, 1949), and Richards (B.S. thesis. University of Delaware, 1950) was made by Shei wood and Pigford (Absorption and Extraction, McGraw-Hill, New York, 1952) and is indicated in Fig. 14-78. 

With the grab sampling technique, a samphng probe is placed at the center of the stack, and a sample is drawn direcfly into an Orsat analyzer or a Fyrite-type combustion-gas analyzer. The sample is then analyzed for carbon dioxide and oxygen content. With these data, the diy molecular weight of the gas stream can then be calculated. 

The parameter z can be obtained from Regnault s results and these show a value of z of 1.064 for hydrogen, 0.9846 for nitrogen, and 0.2695 for carbon dioxide at room temperature and 100 atmospheres pressure. These values are related to tire conections introduced by van der Waals. 

Step 2. With a straight line, connect the point for carbon dioxide on the primary scale with the density-temperature intersection and extend the line to intersect the reference line 1. 

Step 3. Extend a straight line from the point on the reference line 1 through the point on the secondary scale for carbon dioxide and intersect the reference line 2. 

Obviously the availability of a non-carbon fuel, usually hydrogen, would obviate the need for carbon dioxide extraction and disposal, and a plant with combustion of such a fuel becomes a simple solution (Cycle Cl, a hydrogen burning CBT plant, and Cycles C2 and C3, hydrogen burning CCGT plants). 

Cycles A with additional removal equipment for carbon dioxide. sequestration... 

Figure 4-4. Vapor-solid equilibrium constants o) for carbon dioxide, b) for hydrogen sulfide. (From Gas Processors Suppliers Association, Bngineerinq Data Book, 10th Edition.)...

The values lead to a computed value for AH of 60.64 kcal-moT for the reaction, and a predicted value of -94.64 kcal-moT for AHf for carbon dioxide. This value is in excellent agreement with the experimental value of -93.96 kcal-moT ... 

In principle, the sample transfer from the Supercritical state is relatively easily adaptable to other systems, due to the high volatility of the fluid at atmospheric pressure, particularly for carbon dioxide which is the most frequently used fluid. 

Fitze,/. (Textiles) hank, skein, fix, a. fixed fast smart. — fixe Luft, fixed air (old name for carbon dioxide). 

Determine Kga based on inlet alkali normality and percent conversion to carbonate (for carbon dioxide). 

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