摘要:
Mixed matrix polymer membranes capable of separating carbon dioxide from mixtures including carbon dioxide and methane, and processes for purifying methane using the membranes include a selective layer thickness of between about 1000 Angstroms to about 0.005 inch, that include discrete carbon-based molecular sieve particles with sizes of between about 0.5 microns to about 5.0 microns. The particles are formed by pyrolyzing a precursor polymer in the form of a powder or film. The pyrolyzed polymer is then ideally milled to desired small size particles. The preferred ratio of particles to polymer is about 0.25 to about 1.0 by volume. A preferred method for preparing the mixed matrix membrane is by dispersing the particles in a solvent, adding a small quantity of the desired polymer, or 'sizing agent' to 'size' or 'prime' the particles, adding a polymer, casting a film of the polymer solution, and evaporating the solvent to form a mixed matrix membrane film. The polymer is preferably a rigid, glassy polymer, more preferably, with a glass transition temperature above about 150°C. The mixed matrix membrane is preferably in the form of a dense film or a hollow fiber.
摘要:
The present invention is directed to methods (processes) and systems for processing triglyceride-containing, biologically-derived oils to provide for base oils and transportation fuels, wherein partial oligomerization of fatty acids contained therein provide for an oligomerized mixture from which the base oils and transportation fuels can be extracted. Such methods and systems can involve an initial hydrotreating step or a direct isomerization of the oligomerized mixture.
摘要:
The present invention is generally directed to methods and systems for producing biofuels via biomass, waste plastic, and/or Fischer-Tropsch product feeds. Such methods and systems are an improvement over the existing art at least in that they are feed-tolerant (i.e., allow for variability) and provide an economy of scale, while typically retaining the environmental benefits associated with such processing of such feeds.
摘要:
The present disclosure relates to a high molecular weight, monoesterified polyimide polymer. One method as described herein relates to making the high molecular weight, monoesterified polyimide polymer. According to its broadest aspect, the method for making the high molecular weight, monoesterified polyimide polymer comprises the following steps: (a) preparing a polyimide polymer comprising carboxylic acid functional groups from a reaction solution comprising monomers and at least one solvent; and (b) treating the polyimide polymer with a diol at esterification conditions in the presence of dehydrating conditions to form a monoesterified polyimide polymer, wherein the dehydrating conditions at least partially remove water produced during step (b). Such high molecular weight, monoesterified polyimide polymers are useful in forming crosslinked polymer membranes for the separation of fluid mixtures.
摘要:
A process for increasing the yield of olefinc products from a Fischer-Tropsch unit and increasing the yield of products within the lube and diesel boiling range by use of a potassium promoted iron-based catalyst.
摘要:
The methods involve subjecting a C5-11 olefinic feed (5) containing olefins and optional paraffins to a first dimerization zone (30) to yield a first product (35). The first product is then fed to an additional dimerization zone (40) to produce a second product (45) which includes hydrocarbons in the lube base stock.
摘要:
A process is disclosed for preparing a non-zeolitic molecular sieve from a dense gel containing sufficient liquid that the dense gel may be formed into self-supporting particles if desired prior to crystallization. In the process, the dense gel, which is optionally in the form of particles, is heated at crystallization conditions and in the absence of an external liquid phase, so that excess liquid need not be removed at the conclusion of the crystallization step.