Abstract: Provided are solar collection energy storage and energy conversion or chemical conversion systems. Also provided are tubing components, such as for solar receivers, including Mo and having a MoSiB coating on an external surface. The systems can include a solar receiver containing a heat transfer material or chemically reacting material and can operate at temperatures of 700° C. or higher. The solar receiver can include tubing components selected from a Mo tubing component, a MAX phase material tubing component, a MoSiB composite tubing component, or a combination thereof. The Mo component, when present, can include a coating on surfaces of the Mo component that operate above 700° C.

Abstract: A heat transfer system and related method of heat transfer is provided. The heat transfer system includes a tubular receiver positioned to receive heat from a heat source, the receiver comprising one or more enclosed tubes configured for gravity-driven flow of a particulate heat transfer fluid therethrough in a dense, unfluidized state having a particle volume fraction of at least about 25%; and at least one storage vessel in fluid communication with the tubular receiver and positioned to receive the heat transfer fluid therefrom, wherein the particulate heat transfer fluid includes a plurality of particles of a metal-containing material having a melting point of greater than 800 C, the heat transfer fluid being substantially free of a liquid component.

Abstract: A heat transfer system and related method of heat transfer is provided. The heat transfer system includes a tubular receiver positioned to receive heat from a heat source, the receiver comprising one or more enclosed tubes configured for gravity-driven flow of a particulate heat transfer fluid therethrough in a dense, unfluidized state having a particle volume fraction of at least about 25%; and at least one storage vessel in fluid communication with the tubular receiver and positioned to receive the heat transfer fluid therefrom, wherein the particulate heat transfer fluid includes a plurality of particles of a metal-containing material having a melting point of greater than 800 C, the heat transfer fluid being substantially free of a liquid component.

Abstract: A catalyst composition is disclosed. The composition comprises a titanium compound, a solubility promoter, a phosphorus source, a solvent, and optionally a sulfonic acid, a cocatalyst, or both. The cocatalyst can be a cobalt/aluminum catalyst, an antimony compound, or combinations thereof. Also disclosed is a process for producing the composition. The process comprises combining a titanium compound, a solubility promoter, a phosphorus source, a solvent, and optionally a sulfonic acid, a cocatalyst, or both. Further disclosed is a process for using the composition which comprises contacting a carbonyl compound, in the presence of the composition, with an alcohol under a condition suitable for esterification, transesterification, polymerization, or combinations thereof.

Abstract: The present invention relates to an electrochemical cell and a process for converting anhydrous hydrogen halide to halogen gas using a membrane-electrode assembly (MEA) or a separate membrane and electrode arrangement, such as gas diffusion electrodes with a membrane.

Abstract: A catalyst composition is disclosed. The composition comprises a titanium compound, a complexing agent, a solvent, and optionally a cocatalyst. The cocatalyst can be a cobalt/aluminum catalyst, an antimony compound, or combinations thereof. Also disclosed is a process for producing the composition. The process comprises combining a titanium compound, a complexing agent, a solvent, and optionally a cocatalyst. Further disclosed is a process for using the composition which comprises contacting a carbonyl compound, in the presence of the composition, with an alcohol under a condition suitable for esterification, transesterification, polymerization, or combinations thereof.

Abstract: A catalyst composition is disclosed. The composition comprises a titanium compound, a phosphorus compound, an amine, a solvent and optionally a cocatalyst in which the phosphorus compound has a formula selected from the group consisting of (R.sup.1 O).sub.x (PO)(OH).sub.3-x, (R.sup.1 O).sub.y (P.sub.2 O.sub.3)(OH).sub.4-y, and combinations thereof; the amine is a tertiary amine; each R.sup.1 is independently a linear or branched alkyl radical containing from 1 to about 20 carbon atoms per radical; x is 1 or 2; and y is 1, 2, or 3; and the cocatalyst can be a cobalt/aluminum catalyst, an antimony compound, or combinations thereof. Also disclosed is a process for producing the composition. The process comprises combining a titanium compound, a phosphorus compound, a solvent, an amine, a solvent, and optionally a cocatalyst. The phosphorus compound, amie, and solvent are the same as those disclosed above.

Abstract: The invention relates to an electrochemical cell which has an electrode, a membrane disposed in contact with one side of the electrode and a current bus disposed on the other side of the electrode. A current distributor which is disposed between the electrode and the current bus distributes current to the electrode by electronic conduction. The current distributor is made of a non-porous layer of a conductive polymer composite material. The current distributor thus provides a barrier between the current bus and the reactant and the product of the cell. This is especially important in aggressive environments, such as hydrogen chloride. Thus, the cell of the present invention is particularly useful in converting anhydrous hydrogen halide directly to essentially dry halogen gas, such as anhydrous hydrogen chloride to chlorine gas, or in converting aqueous hydrogen chloride to wet chlorine gas.

Abstract: A process and a system produces isocyanate and converts anhydrous hydrogen chloride, which is a by-product of isocyanate production, to chlorine gas in an electrochemical cell. The chlorine is recycled to the isocyanate process. Any unreacted anhydrous hydrogen chloride may be recycled to the electrochemical cell. By recycling the anhydrous hydrogen chloride and the chlorine, the process and system are able to reduce the cost of producing isocyanate. In addition, this process and system process eliminate or at least substantially minimize the problems associated with disposal of anhydrous hydrogen chloride by turning it into a useful starting material in the isocyanate process.

Abstract: The present invention relates to an electrochemical cell, system and process for converting essentially anhydrous hydrogen halide to essentially dry halogen gas. The process of the present invention is useful for converting anhydrous hydrogen halide, in particular, hydrogen chloride, hydrogen fluoride, hydrogen bromide and hydrogen iodide, to a halogen gas, such as chlorine, fluorine, bromine, or iodine. In particular, in the present invention, water is provided to the cation-transporting membrane at the cathode in various ways. The present invention allows for recovery of a released fluid at the cathode-side of the membrane and recycling of the released fluid back to the cathode side of the membrane. In this way, the recovered, released fluid may be recycled to continuously supply water to the membrane, thereby allowing the limiting current density of the cell to be increased and/or controlled.

Abstract: The invention relates to an electrochemical cell which has an electrode, a membrane disposed in contact with one side of the electrode, and a resilient flow field disposed on the other side of the electrode. The resilient flow field provides uniform electrical contact with the electrode. Such a flow field is preferably an elastomer, which can be be made by molding techniques, thereby decreasing the cost and increasing the ease with which such a flow field may be manufactured. The resilient flow field of the present invention is particularly useful in converting anhydrous hydrogen halide directly to essentially dry halogen gas, such as anhydrous hydrogen chloride to chlorine gas, although it may be used in a cell which converts aqueous reactants.

Abstract: The invention relates to an electrochemical cell which has an electrode, which may be either an anode or a cathode, and a membrane disposed in contact with one side of the electrode. An anode current bus is disposed on the other side of the anode, and a cathode current bus is disposed on the other side of the cathode. An anode current distributor collects current from the anode current bus and distributes it to the anode by electronic conduction, and a cathode current distributor collects current from the cathode and distributes it to the cathode bus by electronic conduction. The anode or the cathode current distributor is made of a metal which is treated by either nitriding, boriding or carbiding the metal in order to make the metal oxide growth resistant. In particular, the current distributor comprises tantalum that has been nitrided to form Ta.sub.2 N. The current distributor thus provides a barrier between the current bus and the electrode, and the anolyte, catholyte and products of the cell.

Abstract: The invention relates to an electrochemical cell having an electrode with a catalyst layer and a gas diffusion layer. The cell also includes a mass flow field for directing fluid to and away from the electrode. An additional gas diffusion layer is disposed between the gas diffusion layer and the flow field. This increases the diffusion resistance of the fluid. The electrochemical cell of the present invention is particularly useful in a process for electrochemically converting anhydrous hydrogen halide to essentially dry halogen gas, where it is necessary to control and increase limiting current. It is also possible to use the additional gas diffusion layer in an aqueous process electrochemical cell.

Abstract: The invention relates to an electrochemical cell which has an electrode, a membrane disposed in contact with one side of the electrode and a mass flow field disposed on the other side of the electrode for directing fluid to and away from the electrode. The mass flow field comprises glassy carbon. The cell of the present invention is particularly useful in converting anhydrous hydrogen halide, in particular, hydrogen fluoride, directly to essentially dry halogen gas, such as anhydrous hydrogen fluoride to fluorine gas.

Abstract: The present invention relates to an electrochemical cell and a process for producing a hydroxide solution, sulfuric acid and a halogen gas from a hydrogen halide and a sulfate solution. In particular, the sulfate solution may be an alkali metal sulfate solution, such as sodium or potassium sulfate solution, an alkaline earth metal sulfate solution or an ammonium sulfate solution. The cell and the process may use either an anhydrous or an aqueous hydrogen halide, namely, hydrogen chloride, hydrogen fluoride, hydrogen bromide and hydrogen iodide, to a respective dry halogen gas, such as chlorine, fluorine, bromine, or iodine, to produce hydrogen ions in order to split the alkali metal solution and form the sulfuric acid. The cell has two membrane-electrode assemblies, where an anode is disposed in contact with one membrane, and a cathode is disposed in contact with another membrane. The sulfate solution is fed in between the membrane-electrode assemblies.

Abstract: A conductive inflatable member is provided in an electrochemical cell between an electrode and a current for providing uniform contact pressure, and thus uniform electrical contact between the electrode and the current bus. The inflatable member may comprise a pair of flexible plates, where one plate is thinner than the other plate. The cell of the present invention is particularly useful in converting anhydrous hydrogen halide directly to essentially dry halogen gas, such as anhydrous hydrogen chloride to dry chlorine gas, or in converting aqueous hydrogen halide, such as aqueous hydrogen chloride, to wet chlorine gas.

Abstract: The present invention relates to an electrochemical cell and a process for converting anhydrous hydrogen halide to halogen gas using a membrane-electrode assembly (MEA) or a separate membrane and electrode arrangement, such as gas diffusion electrodes with a membrane.

Abstract: The invention relates to a process for electrochemically converting anhydrous hydrogen halide, such as hydrogen chloride, hydrogen fluoride, hydrogen bromide and hydrogen iodide, to essentially dry halogen gas, such as chlorine, fluorine, bromine and iodine gas, respectively. In a preferred embodiment, the present invention relates to a process for electrochemically converting anhydrous hydrogen chloride to essentially dry chlorine gas. This process allows the production of high-purity chlorine gas. In this process, molecules of essentially anhydrous hydrogen chloride are transported through an inlet of an electrochemical cell. The molecules of the essentially anhydrous hydrogen chloride are oxidized at the anode of the cell to produce essentially dry chlorine gas and protons, which are transported through the membrane of the cell. The transported protons are reduced at the cathode to form either hydrogen gas or water.

Abstract: The present invention relates to an electrochemical cell and a process for converting anhydrous hydrogen halide to halogen gas using a membrane-electrode assembly (MEA) or a separate membrane and electrode arrangement, such as gas diffusion electrodes with a membrane.

Abstract: A particular anode comprising an electrochemically active material selected from the group .[.comprising.]. .Iadd.consisting of .Iaddend.the oxides of the elements tin, germanium and lead and mixtures comprising at least one of the respective oxides of such elements is useful in an electrochemical cell for the direct production of essentially dry halogen gas from essentially anhydrous halogen halide, or in a process for such production of essentially dry halogen gas. This cell or process may be used to produce halogen gas such as chlorine, bromine, fluorine and iodine from a respective anhydrous hydrogen halide, such as hydrogen chloride, hydrogen bromide, hydrogen fluoride and hydrogen iodide.