摘要:
An organic acid is separated from a fermentation broth by using an adsorbent comprising a water-insoluble macroreticular or gel weakly basic anionic exchange resin possessing tertiary amine or pyridine functional groups or a strongly basic anionic exchange resin possessing quaternary amine functional groups. The resins are in sulfate form and have a cross-linked acrylic or styrene resin matrix. The organic acid is desorbed with water or dilute inorganic acid, e.g., sulfuric. The pH of the feed is maintained below the first ionization constant (pKa.sub.1) of the organic acid to obtain high selectivity.
摘要:
An adsorbent for removal of impurities from silicone based solvents is presented. The adsorbent is regenerable for repeated use in cleaning silicone based solvents.
摘要:
An adsorbent for removal of impurities from silicone based solvents is presented. The adsorbent is regenerable for repeated use in cleaning silicone based solvents.
摘要:
A novel integrated system for the co-production of heat and electricity for residences or commercial buildings is based on the cracking of hydrocarbons to generate hydrogen for a fuel cell. Compared to prior art reforming methods for hydrogen production, the cracking reaction provides an input stream to the fuel cell that is essentially free of CO, a known poison to the anode catalyst in many fuel cell designs, such as PEM fuel cells. The cracking reaction is coupled with an air or steam regeneration cycle to reactivate that cracking catalyst for further use. This regeneration can provide a valuable source of heat or furnace fuel to the system. A novel control method for system adjusts the durations of the cracking and regeneration cycles to optimize the recovery of reaction heat.
摘要:
Citric acid is separated from a fermentation broth by using an adsorbent comprising a water-insoluble macroreticular or gel weakly basic anionic exchange resin possessing tertiary amine functional groups or pyridine functional groups, said anionic exchange resin comprising a cross-linked acrylic or styrene resin matrix. Citric acid is desorbed by water or dilute sulfuric acid. The pH of the feed is maintained below the first ionization constant (pKa.sub.1) of citric acid to maintain selectivity.
摘要:
Lactic acid is separated from a fermentation broth by using an adsorbent comprising a water-insoluble macroreticular or gel weakly basic anionic exchange resin possessing tertiary amine or pyridine functional groups or a strongly basic anionic exchange resin possessing quaternary amine fuctional groups. The resins are in sulfate form and have a cross-linked acrylic or styrene resin matrix. Lactic acid is desorbed with water or dilute inorganic acid, e.g., sulfuric. The pH of the feed is maintained below the ionization constant (pKa) of lactic acid to obtain high selectivity.
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.