Sulfur dioxide, compressibility

CGA G-3, Sulfur Dioxide, Compressed Gas Association, Inc., 1235 Jefferson Davis Highway, Arlington, VA 22202. 

Several types of fluids are used as refrigerants in mechanical compression systems ammonia, halocarbon compounds, hydrocarbons, carbon dioxide, sulfur dioxide, and cryogenic fluids. A wide temperature range therefore is afforded. These fluids boil and condense isotherm ally. The optimum temperature or pressure at which each can be used can be deterrnined from the economics of the system. The optimum refrigerant can be deterrnined only... 

Chemica.1 Properties. Reviews of carbonyl sulfide chemistry are available (18,23,24). Carbonyl sulfide is a stable compound and can be stored under pressure ia steel cylinders as compressed gas ia equiUbrium with Hquid. At ca 600°C carbonyl sulfide disproportionates to carbon dioxide and carbon disulfide at ca 900°C it dissociates to carbon monoxide and sulfur. It bums with a blue flame to carbon dioxide and sulfur dioxide. Carbonyl sulfide reacts... 

The Inco flash smelting process produces a very high strength sulfur dioxide gas by using pure oxygen for smelting. Liquid sulfur dioxide is obtained upon compression. 

Sulfur Dioxide, Paniplilet G-3, 3 ed.. Compressed Gas Association, New York, 1964. 

Sulfur is widely distributed as sulfide ores, which include galena, PbS cinnabar, HgS iron pyrite, FeS, and sphalerite, ZnS (Fig. 15.11). Because these ores are so common, sulfur is a by-product of the extraction of a number of metals, especially copper. Sulfur is also found as deposits of the native element (called brimstone), which are formed by bacterial action on H,S. The low melting point of sulfur (115°C) is utilized in the Frasch process, in which superheated water is used to melt solid sulfur underground and compressed air pushes the resulting slurry to the surface. Sulfur is also commonly found in petroleum, and extracting it chemically has been made inexpensive and safe by the use of heterogeneous catalysts, particularly zeolites (see Section 13.14). One method used to remove sulfur in the form of H2S from petroleum and natural gas is the Claus process, in which some of the H2S is first oxidized to sulfur dioxide ... 

Materials and Purifications. 2-Methyl pentene-1 (Aldrich) was distilled under normal pressure at 62°C after refluxing for one hour 1n the presence of A1L1H.. Methyl methacrylate and para-methyl styrene (Aldrich) were distilled under reduced pressure at about 60°C the purified monomers were sealed and stored 1n refrigerator before use. The compressed gas, sulfur dioxide (Matheson), was led through a P208 tower before Introduced Into reaction system. Hydroxyethyl acrylate (Aldrich) was used for polymerization without further purification. 

In the Wellman-Lord process, sodium sulfite is used to capture the sulfur dioxide. The sodium bisulfite thus formed is later heated to evolve sulfur dioxide and regenerate the sulfite scrubbing material. The sulfur dioxide-rich product stream can be compressed or liquefied and oxidized to sulfuric acid, or reduced to sulfur. 

Fill A with well-activated charcoal to within 1 to 2 cm. of the overflow tube E. Immerse A in D and conduct in the two gases sulfur dioxide and chlorine, in equal volumes, best from cylinders of compressed gas. Action begins at once with considerable heat evolution, and after a time the union of the gases becomes almost quantitative. The flow of the two gases should be regulated so that the least number of bubbles escapes through the liquid collecting in A. Temperature is of... 

Sulfur Dioxide. This compound is a useful reactant and low-temperature solvent. The commercial compressed gas may be condensed at liquid nitrogen temperature and atmospheric gases pumped away. Moisture is removed by passing it through a trap containing P4O 0 dispersed in glass wool. 

Caution Sulfur dioxide gas is intensely irritating to the eyes, throat, and upper respiratory system. Liquid sulfur dioxide may cause skin burns, which result from the freezing effect of the liquid on tissue. Safety precautions to be observed in handling the material are specified in Pamphlet G-3 published by the Compressed Gas Association, 4221 Walney Road, Fifth Floor, Chantilly, VA 20151-2923. 

Sulfur dioxide and sulfites have long been used as preservatives, serving both as antimicrobial substance and as antioxidant. Their use as preservatives in wine dates back to Roman times. Sulfur dioxide is a gas that can be used in compressed form in cylinders. It is liquid under pressure of 3.4 atm and can be injected directly in liquids. It can also be used to prepare solutions in ice cold water. It dissolves to form sulfurous acid. Instead of sulfur dioxide solutions, a number of sulfites can be used (Table 11-2) because, when dissolved in water, they all yield active S02. 

Related Calculations. Use this procedure to compute the pressure loss, velocity, and flow rate in compressed-air and gas lines of any length. Gases for which this procedure can be used include ammonia, carbon dioxide, carbon monoxide, ethane, ethylene, hydrogen, hydrogen sulfide, isobutane, methane, nitrogen, -butane. oxygen, propane, propylene, and sulfur dioxide. 

Given in the literature are vapor pressure data for acetaldehyde and its aqueous solutions (1—3) vapor—liquid equilibria data for acetaldehyde—ethylene oxide [75-21-8] (1), acetaldehyde—methanol [67-56-1] (4), sulfur dioxide [7446-09-5]— acetaldehyde—water (5), acetaldehyde—water—methanol (6) the azeotropes of acetaldehyde—butane [106-97-8] and acetaldehyde—ethyl ether (7) solubility data for acetaldehyde—water—methane [74-82-8] (8), acetaldehyde—methane (9) densities and refractive indexes of acetaldehyde for temperatures 0—20°C (2) compressibility and viscosity at high pressure (10) thermodynamic data (11—13) pressure—enthalpy diagram for acetaldehyde (14) specific gravities of acetaldehyde—paraldehyde and acetaldehyde—acetaldol mixtures at 20/20°C vs composition (7) boiling point vs composition of acetaldehyde—water at 101.3 kPa (1 atm) and integral heat of solution of acetaldehyde in water at 11°C (7). 

Suppose 1 mol of gaseous sulfur dioxide is compressed at a temperature fixed at 30.0°C. The volume is measured at each pressure, and a graph of volume against pressure is constructed (Fig. 10.18). At low pressures, the graph shows the inverse dependence (V 1/F) predicted by the ideal gas law. As the pressure increases, deviations appear because the gas is not ideal. At this temperature, attractive forces dominate therefore, the volume falls below its ideal gas value and approaches 4.74 L (rather than 5.50 L) as the pressure approaches 4.52 atm. 

Derivation (1) By roasting pyrites in special furnaces. The gas is readily liquefied by cooling with ice and salt or at a pressure of three atmospheres. (2) By purifying and compressing sulfur dioxide gas from smelting operations. (3) By burning sulfur. 

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