Abstract: Systems and methods are provided for using fuel cell staging to reduce or minimize variations in current density when operating molten carbonate fuel cells with elevated CO2 utilization. The fuel cell staging can mitigate the amount of alternative ion transport that occurs when operating molten carbonate fuel cells under conditions for elevated CO2 utilization.

Abstract: A reforming element for a molten carbonate fuel cell stack and corresponding methods are provided that can reduce or minimize temperature differences within the fuel cell stack when operating the fuel cell stack with enhanced CO2 utilization. The reforming element can include at least one surface with a reforming catalyst deposited on the surface. A difference between the minimum and maximum reforming catalyst density and/or activity on a first portion of the at least one surface can be 20% to 75%, with the highest catalyst densities and/or activities being in proximity to the side of the fuel cell stack corresponding to at least one of the anode inlet and the cathode inlet.

Abstract: Capture of hydrogen sulfide from a gas mixture may be accomplished using an aqueous solution comprising an amine. Certain sterically hindered amines may selectively form a reaction product with hydrogen sulfide under kinetically controlled contacting conditions and afford a light phase and a heavy phase above a critical solution temperature, wherein the hydrogen sulfide may be present in either phase. Upon separation of the light phase from the heavy phase, processing of one of the phases may take place to remove hydrogen sulfide therefrom. Recycling of the amine to an absorber tower may then take place to promote capture of additional hydrogen sulfide.

Abstract: A reforming element for a molten carbonate fuel cell stack and corresponding methods are provided that can reduce or minimize temperature differences within the fuel cell stack when operating the fuel cell stack with enhanced CO2 utilization. The reforming element can include at least one surface with a reforming catalyst deposited on the surface. A difference between the minimum and maximum reforming catalyst density and/or activity on a first portion of the at least one surface can be 20% to 75%, with the highest catalyst densities and/or activities being in proximity to the side of the fuel cell stack corresponding to at least one of the anode inlet and the cathode inlet.

Abstract: The present disclosure provides methods for determining adsorption isotherms for complex mixtures. In at least one embodiment, a method for obtaining adsorption isotherms for liquid mixtures includes providing a column comprising an adsorbent. The method includes delivering a composition to the column, the composition comprising a multi-component feed and a solvent. The method includes collecting a sample from the column and introducing the sample to a two dimensional gas chromatograph to determine a time-series concentration of one or more components of the sample. The method includes integrating the time-series concentration of at least one of the one or more components to determine an isotherm of the at least one component. The method includes obtaining quantitative information of the at least one component, based on the isotherm of the at least one component.

Abstract: Systems and methods are provided for using fuel cell staging to reduce or minimize variations in current density when operating molten carbonate fuel cells with elevated CO2 utilization. The fuel cell staging can mitigate the amount of alternative ion transport that occurs when operating molten carbonate fuel cells under conditions for elevated CO2 utilization.

Abstract: Systems and methods are provided for using fuel cell staging to reduce or minimize variations in current density when operating molten carbonate fuel cells with elevated CO2 utilization. The fuel cell staging can mitigate the amount of alternative ion transport that occurs when operating molten carbonate fuel cells under conditions for elevated CO2 utilization.

Abstract: A molecular separation method can include: passing a deasphalted oil stream through a reactor containing an active substrate, wherein the catalytic active substrate adsorbs heteroatom species from the deasphalted oil stream and produces a pretreated hydrocarbon feed stream essentially free of 4+ ring aromatic molecules (ARC 4+ species), metal species, and heteroatom species; and chromatographically separating with a simulated moving bed apparatus or a true moving bed apparatus (SMB/TMB) the pretreated hydrocarbon feed stream into a saturate fraction and an aromatics fraction.

Abstract: A process for selectively separating H2S from a gas mixture which also comprises CO2is disclosed. A stream of the gas mixture is contacted with an absorbent solution comprising one or more amines, alkanolamines, hindered alkanolamines, capped alkanolamines, or mixtures thereof. The H2S/CO2 selectivity of the absorbent solution is preferably greater than about 4.0 for an acid gas loading [mol(CO2+H2S)/mol(amine)] between about 0.2 and about 0.6, and is achieved by reducing pH of the absorbent solution.

Abstract: Systems and methods are provided for operating molten carbonate fuel cells to allow for periodic regeneration of the fuel cells while performing elevated CO2 capture. In some aspects, periodic regeneration can be achieved by shifting the location within the fuel cells where the highest density of alternative ion transport is occurring. Such a shift can result in a new location having a highest density of alternative ion transport, while the previous location can primarily transport carbonate ions. Additionally or alternately, periodic regeneration can be performed by modifying the input flows to the fuel cell and/or relaxing the operating conditions of the fuel cell to reduce or minimize the amount of alternative ion transport.

Abstract: A process for selectively separating H2S from a gas mixture which also comprises CO2 is disclosed. A stream of the gas mixture is contacted with an absorbent solution comprising one or more amines, alkanolamines, hindered alkanolamines, capped alkanolamines, or mixtures thereof. The H2S/CO2 selectivity of the absorbent solution is preferably greater than about 4.0 for an acid gas loading [mol(CO2+H2S)/mol(amine)] between about 0.2 and about 0.6, and is achieved by reducing pH of the absorbent solution.

Abstract: A molecular separation method can include: passing a deasphalted oil stream through a reactor containing an active substrate, wherein the catalytic active substrate adsorbs heteroatom species from the deasphalted oil stream and produces a pretreated hydrocarbon feed stream essentially free of 4+ ring aromatic molecules (ARC 4+ species), metal species, and heteroatom species; and chromatographically separating with a simulated moving bed apparatus or a true moving bed apparatus (SMB/TMB) the pretreated hydrocarbon feed stream into a saturate fraction and an aromatics fraction.

Abstract: Systems and methods are provided for using fuel cell staging to reduce or minimize variations in current density when operating molten carbonate fuel cells with elevated CO2 utilization. The fuel cell staging can mitigate the amount of alternative ion transport that occurs when operating molten carbonate fuel cells under conditions for elevated CO2 utilization.

Abstract: A reforming element for a molten carbonate fuel cell stack and corresponding methods are provided that can reduce or minimize temperature differences within the fuel cell stack when operating the fuel cell stack with enhanced CO2 utilization. The reforming element can include at least one surface with a reforming catalyst deposited on the surface. A difference between the minimum and maximum reforming catalyst density and/or activity on a first portion of the at least one surface can be 20% to 75%, with the highest catalyst densities and/or activities being in proximity to the side of the fuel cell stack corresponding to at least one of the anode inlet and the cathode inlet.

Abstract: Systems and methods are provided for operating molten carbonate fuel cells to allow for periodic regeneration of the fuel cells while performing elevated CO2 capture. In some aspects, periodic regeneration can be achieved by shifting the location within the fuel cells where the highest density of alternative ion transport is occurring. Such a shift can result in a new location having a highest density of alternative ion transport, while the previous location can primarily transport carbonate ions. Additionally or alternately, periodic regeneration can be performed by modifying the input flows to the fuel cell and/or relaxing the operating conditions of the fuel cell to reduce or minimize the amount of alternative ion transport.

Abstract: In a process for separating one or more 3,3?-, 3,4?- and 4,4?-dimethyl biphenyl isomers, a feed comprising the isomers is contacted with a zeolite adsorbent which contains one or more metal cations in the +1 or +2 oxidation states. Separation processes for each of the 3,3?-, 3,4?- and 4,4?-dimethyl biphenyl isomers is provided.

Abstract: A process for separating dimethyl biphenyl (DMBP) isomers, including contacting a mixture of 3,3?-DMBP, 3,4?-DMBP and 4,4?-DMBP in a first solvent with a 12-member ring zeolite exchanged with potassium or barium, or combinations thereof, and adsorbing the 3,3?-DMBP onto the 12-member ring zeolite, such as by passing the mixture through at least one packed bed of the potassium and/or barium exchanged 12-member ring zeolite.

Abstract: A system and process for selectively separating H2S from a gas mixture which also comprises CO2 is disclosed. A water recycle stream is fed to the absorber in order to create a higher concentration absorbent above the recycle feed and having a greater H2S selectivity at lower acid gas loadings, and a more dilute absorbent below the recycle feed and having a greater H2S selectivity at higher acid gas loadings. Also disclosed is a system and process for selectively separating H2S by utilizing two different absorbents, one absorbent for the upper section of the absorber, tailored to have a greater H2S selectivity at lower acid gas loadings, and a second absorbent for the lower section of the absorber, tailored to have a greater H2S selectivity at higher acid gas loadings.

Abstract: A process for selectively separating H2S from a gas mixture which also comprises CO2 is disclosed. A stream of the gas mixture is contacted with an absorbent solution comprising one or more amines, alkanolamines, hindered alkanolamines, capped alkanolamines, or mixtures thereof. The H2S/CO2 selectivity of the absorbent solution is preferably greater than about 4.0 for an acid gas loading [mol(CO2+H2S)/mol(amine)] between about 0.2 and about 0.6, and is achieved by reducing pH of the absorbent solution.

Abstract: A process for separating dimethyl biphenyl (DMBP) isomers, including contacting a mixture of 3,3?-DMBP, 3,4?-DMBP and 4,4?-DMBP in a first solvent with a 12-member ring zeolite exchanged with potassium or barium, or combinations thereof, and adsorbing the 3,3?-DMBP onto the 12-member ring zeolite, such as by passing the mixture through at least one packed bed of the potassium and/or barium exchanged 12-member ring zeolite.