Grades ethane

The carbon dioxide was supplied by Air Products and Chexxiicals, Inc., with a stated purity of 99.99% and research grade ethane was obtained from MG Industries. Crude methyl oleate (KODAK T.G. containing 65%-75% methyl oleate) was purified to 98%-99% (including methyl linoleate) using vacuum distillation. 

C.P. grade ethane and ethylene were used as monomers. The flow rate of monomer was measured by a rotameter and the monomer pressure in the reactor was determined with a McLeod gauge. 

A purified grade of l,l-di-( -chlorophenyl)-2,2,2-trichloro-ethane (DDT) melting at 105-106° should be used. It can be obtained by crystallizing the technical material from alcohol. Thus, 100 g. of technical DDT melting at 81-96°, when crystallized from 550 ml. of 95% ethanol, gave about 70 g. of material melting at 105-106°. 

The specifications for the feed to the indirect hydration route to IPA plant can be loose. Refinery grade propylene, even with some small amounts of ethane and ethylene can be used, because the C2S and propane don t react. They just pass through the process. As a matter of fact, the process acts as kind of a C3 splitter, since about 50% of the propylene gets converted to IPA in each pass through the reactor, leaving high purity propane behind. 

DCP in air samples and, therefore, should seldom cause a problem (11, 12). The other potential interferent, 1,2-dichloro-ethane, is an impurity in reagent-grade 1,2-DCP but typically represents less than 1% (w/w) of the reagent (13). Thus, this compound should not ordinarily pose an interference problem. 

A mixture of benzaldehyde (1.06 g, 10 mmol), ethane-1,2-diol (0.62 g, 10 mmol) and commercial grade cadmium iodide (1.85 g, 5 mmol) were thoroughly mixed at room temperature in an Erlenmeyer flask and placed in a commercial micro-wave oven operating at 2450 MHz frequency. After irradiation of the mixture for 1.5 min (monitored vide TLC) it was cooled to room temperature, extracted with dichloromethane, washed with sodium thiosulfate and dried over anhydrous Na2S04- Evaporation of the solvent gave almost pure products and there was no evidence for the formation of any hydroxy ester or iodoester. Further purification was achieved by column chromatography on silica gel using 1 5 chloroform-petroleum ether as eluent. 

The 2-cyclohexen-l-one (Aldrich, 97%) was used as received. It was loaded into the cell to yield a reaction concentration of 29 mM, which was verified spectrophotometrically. Ethane (CP grade, Big Three Gases) was passed through an in-line activated carbon filter and an Oxy-Trap (Alltech Associates Inc.) prior to use to remove impurities and oxygen, respectively. 

Acetylene in the deethanizer overhead is hydrogenated (10) or recovered. The ethylene-ethane stream is fractionated (11) and polymer-grade ethylene is recovered. Ethane leaving the bottom of the ethylene fractionator is recycled and cracked to extinction. 

Cracked gases are cooled and fractionated to remove fuel oil and water (2-5) then compressed (6), processed for acid-gas removal (8) and dried (9). The C3 and lighter material is separated as an overhead product in the depropanizer (10) and acetylene is hydrogenated in the acetylene converter (11). The acetylene converter effluent is processed in the demethanizer system (12-14) to separate the fuel gas and hydrogen products. The demethanizer bottoms is sent to the deethanizer (15) from which the overhead flows to the C2-splitter (16), which produces the polymer-grade ethylene product and the ethane stream, which is typically recycled to the furnaces as a feedstock. The deethanizer bottoms flows to the C3-splitter (18) where the polymer-grade propylene is recovered... 

Application To produce polymer-grade ethylene and propylene by thermal cracking of hydrocarbon fractions—from ethane through naphtha up to hydrocracker residue. Byproducts are a butadiene-rich C4 stream, a Cg— Cg gasoline stream rich in aromatics and fuel oil. 

The heavier C2 stream is deethanized (7) and C2 overhead passes to the MP ethylene-ethane fractionator (9) integrated with C2 refrigeration system. The lighter C2 stream is routed directly to the ethylene-ethane fractionator (9). Polymer-grade ethylene product is sent overhead from the ethylene-ethane fractionator. Acetylene recovery may optionally be installed upstream of the ethylene-ethane fractionator (8). 

Application To produce polymer-grade ethylene and propylene, a butadiene-rich C4 cut, an aromatic C6-C8 rich raw pyrolysis gasoline, and a high-purity hydrogen by steam pyrolysis of hydrocarbons ranging from ethane to vacuum gas oils. 

Many cracker operations are integrated into the downstream production of polymers and resins. For ethane cracking this usually means integration into the production of various polyethylene grades. 

The surfactant AOT ( purum grade, Fluka) was purified as described by Kotlarchyk 22). The AOT solution was filtered through a 0.2-)im Millipore filter prior to drying in vacuo for eight hours. The AOT was stored in a desiccator over anhydrous calcium sulfate. The molar water-to-AOT ratio (W) was assumed to be 1 in the purified, dried solid (2J ). Water was distilled and filtered through a Millipore Milli-Q system. Ethane, propane ("CP" grade, Linde), and xenon (Research grade, Linde) were used as received. The alkanes had a reported purity of >99% (Aldrich) and were used as received. 

Materiala. Nonionic surfactants Brij 52 (B52) and Brij 30 (B30) were obtained from the Sigma Chemical Company and used as received. These surfactants are ethoxylated alcohols with the nominal structures Cie a and C12E4, respectively, where E represents the number of ethylene oxide units. Acrylamide was obtained from the Aldrich Chemical Company (Gold Label 99-1-%) and recrystallized twice from chloroform. Azo bis(isobutyrnitrile) (AIBN), obtained from the Alfa Products Division of Morton Thiokol, was recrystallized from methanol. Water was doubly deionized. Propane obtained from Union Carbide Linde Division (CP Grade) and ethane from Air Products (CP Grade) were used without further purification. 

Ethylene dimerization and oligomerization (Dimersol and Phillips process) is much less developed, because of the economic situation. Even in the most favorable conditions, nickel catalysts unavoidably produce a mixture of 1- and 2-butenes and ethylene is generally more expensive than 2-butene and 1-bu-tene/2-butene mixtures. Feedstocks are either polymerization-grade ethylene or a 50 50 mixture with ethane. In this latter case a gas phase is inevitably present in the reactor. The product composition is strongly dependent on ethylene conversion. The Phillips process probably uses NiCl2 2 PBus as catalyst. Due to the very high reactivity of ethylene, catalyst consumption is remarkably low. 

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