2670results about "Hydrocarbon purification/separation" patented technology

A process for the recovery of ethane, ethylene, propane, propylene and heavier hydrocarbon components from a hydrocarbon gas stream is disclosed. In recent years, the preferred method of separating a hydrocarbon gas stream generally includes supplying at least portions of the gas stream to a fractionation tower having at least one reboiler, and often one or more side reboilers, to supply heat to the column by withdrawing and heating some of the tower liquids to produce stripping vapors that separate the more volatile components from the desired components. The reboiler and side reboilers (if any) are typically integrated into the feed stream cooling scheme to provide at least a portion of the refrigeration needed to condense the desired components for subsequent fractionation in the distillation column. In the process disclosed, the tower reboiling scheme is modified to use one or more tower liquid distillation streams from a point higher in the column than is used in the conventional reboiling scheme, providing colder stream(s) for the reboiler(s) that allow more effective cooling of the feed streams and thereby improve the efficiency with which the desired components are recovered. In addition, the tower liquid streams withdrawn from a higher point in the column contain larger quantities of the more volatile components, which when vaporized provide better stripping of undesirable components like carbon dioxide without reducing the recovery of the desired components. The heated distillation stream is returned to a lower point on the fractionation tower that is separated from the withdrawal point by at least one theoretical stage.

The ability to design and construct solid-state materials with pre-determined structures is a grand challenge in chemistry. An inventive strategy based on reticulating metal ions and organic carboxylate links into extended networks has been advanced to a point that has allowed the design of porous structures in which pore size and functionality can be varied systematically. MOF-5, a prototype of a new class of porous materials and one that is constructed from octahedral Zn—O—C clusters and benzene links, was used to demonstrate that its 3-D porous system can be functionalized with the organic groups, —Br, —NH2, —OC3H7, —OC5H11, —H4C2, and —H4C4, and its pore size expanded with the long molecular struts biphenyl, tetrahydropyrene, pyrene, and terphenyl. The ability to direct the formation of the octahedral clusters in the presence of a desired carboxylate link is an essential feature of this strategy, which resulted in the design of an isoreticular (having the same framework topology) series of sixteen well-defined materials whose crystals have open space representing up to 91.1% of the crystal volume, and homogeneous periodic pores that can be incrementally varied from 3.8 to 28.8 angstroms. Unlike the unpredictable nature of zeolite and other molecular sieve syntheses, the deliberate control exercised at the molecular level in the design of these crystals is expected to have tremendous implications on materials properties and future technologies. Indeed, data indicate that members of this series represent the first monocrystalline mesoporous organic / inorganic frameworks, and exhibit the highest capacity for methane storage (155 cm3 / cm3 at 36 atm) and the lowest densities (0.41 to 0.21 g / cm3) attained to date for any crystalline material at room temperature.

A premium synthetic lubricating oil base stock having a high VI and low pour point is made by hydroisomerizing a Fischer-Tropsch synthesized waxy, paraffinic feed wax and then dewaxing the hydroisomerate to form a 650-750° F.+ dewaxate. The waxy feed has an initial boiling point in the range of about 650-750° F., from which it continuously boils up to at least 1050° F. and has a T90-T10 temperature difference of at least 350° F. The feed is preferably hydroisomerized without any pretreatment, other than optional fractionation. The 650-750° F.+ dewaxate is fractionated into two or more base stocks of different viscosity.

Compositions and methods for producing olefins are described herein. The olefins can be used to produced biofuels.

Process for the production of gasoline with a low sulfur content that comprises at least the following two stages:a) a hydrogenation stage of the unsaturated sulfur containing compounds,b) a decomposition stage of saturated sulfur containing compounds,and optionally a preliminary stage for pretreatment of the feedstock such as selective hydrogenation of dienes.