摘要:
An improved mixed matrix membrane for the separation of gases comprises a nitrogen containing compound such as an amine, silicone rubber and activated carbon on a porous support. The membrane may also comprise a carbonate such as potassium carbonate and a plasticizer such as polyethylene glycol. Membranes of this design may be used in processing natural gas or other gases. The gases which may be separated by the membrane include mixtures of methane and carbon dioxide, mixtures of oxygen and nitrogen, and mixtures of carbon dioxide and nitrogen.
摘要:
This invention discloses a composition of, a method of making, and an application of high plasticization-resistant chemically cross-linked organic-inorganic hybrid membranes such as cross-linked cellulose acetate-cellulose triacetate-polyurethanepropylsilsesquioxane membranes. These cross-linked membranes with covalently interpolymer-chain-connected hybrid networks were prepared via a sol-gel condensation polymerization of cross-linkable organic polymer-organosilicon alkoxide precursor membrane materials. CO2 plasticization tests on these cross-linked membranes demonstrate extremely high CO2 plasticization resistance under CO2 pressure up to 5516 kPa (800 psig). These new cross-linked membranes can be used not only for gas separations such as CO2/CH4 and CO2/N2 separations, O2/N2 separation, olefin/paraffin separations (e.g. propylene/propane separation), iso/normal paraffins separations, but also for liquid separations such as desalination.
摘要:
This invention discloses a composition of, a method of making, and an application of high plasticization-resistant chemically cross-linked organic-inorganic hybrid membranes such as cross-linked cellulose acetate-cellulose triacetate-polyurethanepropylsilsesquioxane membranes. These cross-linked membranes with covalently interpolymer-chain-connected hybrid networks were prepared via a sol-gel condensation polymerization of cross-linkable organic polymer-organosilicon alkoxide precursor membrane materials. CO2 plasticization tests on these cross-linked membranes demonstrate extremely high CO2 plasticization resistance under CO2 pressure up to 5516 kPa (800 psig). These new cross-linked membranes can be used not only for gas separations such as CO2/CH4 and CO2/N2 separations, O2/N2 separation, olefin/paraffin separations (e.g. propylene/propane separation), iso/normal paraffins separations, but also for liquid separations such as desalination.
摘要:
A simulated moving bed adsorptive separation process for preparing the separate feed streams charged to naphtha reforming unit and a steam cracking unit has been developed. The feed stream to the overall unit is passed into the adsorptive separation unit. The desorbent in the adsorptive separation is C12 hydrocarbons. The simulated moving bed adsorptive separation separates the components of the feed stream into a normal paraffin stream, which is charged to the steam cracking process, and non-normal hydrocarbons which are passed into a reforming zone. The desorbent is readily separated from the normal paraffin stream and from the non-normal paraffin stream and the simulated moving bed adsorption zone is operated at an A/Fn ratio of from about 0.90 to about 0.92.
摘要:
Processes for olefin/paraffin separation utilizing porous, hydrophobic poly(ether ether ketone) (PEEK) membranes are provided. In accordance with an exemplary embodiment, a process for olefin/paraffin separation comprises providing a porous membrane formed of PEEK polymer functionalized with hydrophobic groups, the porous membrane having a first surface and a second surface. The first surface of the porous membrane is contacted with a feed comprising an olefin and a paraffin and a permeate is caused to flow from the second surface of the porous membrane. The permeate has a concentration of the paraffin that is higher than a concentration of the paraffin of the feed.
摘要:
The present invention is for crosslinked membranes and in particular for crosslinked poly(ethylene oxide)-cellulose acetate-silsesquioxane (PEO-CA-Si) organic-inorganic hybrid membranes and their use in gas separation. These crosslinked PEO-CA-Si membranes were prepared by in-situ sol-gel co-condensation of crosslinkable PEO-organotrialkoxysilane and CA-organotrialkoxysilane polymers in the presence of acetic acid catalyst during the formation of membranes. The crosslinkable PEO- and CA-organotrialkoxysilane polymers were synthesized via the reaction between the hydroxyl groups on PEO (or on CA) and the isocyanate on organotrialkoxysilane to form urethane linkages under mild conditions. The crosslinked PEO-CA-Si membranes exhibited both increased selectivity of CO2/N2 and CO2 permeability as compared to a CA membrane, suggesting that these membranes are very promising for gas separations such as CO2/N2 separation.
摘要:
The present invention is for crosslinked membranes and in particular for crosslinked poly(ethylene oxide)-cellulose acetate-silsesquioxane (PEO-CA-Si) organic-inorganic hybrid membranes and their use in gas separation. These crosslinked PEO-CA-Si membranes were prepared by in-situ sol-gel co-condensation of crosslinkable PEO-organotrialkoxysilane and CA-organotrialkoxysilane polymers in the presence of acetic acid catalyst during the formation of membranes. The crosslinkable PEO- and CA-organotrialkoxysilane polymers were synthesized via the reaction between the hydroxyl groups on PEO (or on CA) and the isocyanate on organotrialkoxysilane to form urethane linkages under mild conditions. The crosslinked PEO-CA-Si membranes exhibited both increased selectivity of CO2/N2 and CO2 permeability as compared to a CA membrane, suggesting that these membranes are very promising for gas separations such as CO2/N2 separation.
摘要:
Adsorbents and methods for the adsorptive separation of para-xylene from a mixture containing at least one other C8 aromatic hydrocarbon (e.g., a mixture of ortho-xylene, meta-xylene, para-xylene, and ethylbenzene) are described. Suitable adsorbents comprise nano-size zeolite X having an average crystallite size of less than about 500 nanometers. The adsorbents provide both improved capacity and mass transfer, which is especially advantageous for improving productivity in low temperature, low cycle time adsorptive separation operations in a simulated moving bed mode.
摘要:
A novel process effective for the removal of organic sulfur compounds, organic nitrogen compounds and light olefins from liquid hydrocarbons is disclosed. The process more specifically addresses the removal of these contaminants from aromatic compounds including benzene and toluene and from naphtha. The liquid hydrocarbons are contacted with a blend of at least one metal oxide and an acidic zeolite. Preferably, the metal oxide comprises nickel oxide and molybdenum oxide and the acidic zeolite is acidic stabilized zeolite Y. This blend has a significant capacity for adsorption of impurities and can be regenerated by oxidative treatment.
摘要:
The present invention comprises a process for removal of oxygenates from a paraffin-rich or olefin-rich paraffin stream which comprises passing a feed stream, comprising one or more C10 to C15 feed paraffins or C10 to C15 olefin-rich paraffin stream and one or more oxygenates through an adsorbent bed comprising one or more adsorbents selected from silica gel, activated alumina and sodium x zeolites to remove essentially all of said oxygenates; and recovering said paraffins. A second adsorbent bed may be employed to more thoroughly remove these oxygenates.