Carbon nanofiber doped alumina (Al-CNF) supported MoCo catalysts in hydrodesulfurization (HDS), and/or boron doping, e.g., up to 5 wt % of total catalyst weight, can improve catalytic efficiency. Al-CNF-supported MoCo catalysts, (Al-CNF-MoCo), can reduce the sulfur concentration in fuel, esp. liquid fuel, to below the required limit in a 6 h reaction time. Thus, Al-CNF-MoCo has a higher catalytic activity than Al—MoCo, which may be explained by higher mesoporous surface area and better dispersion of MoCo metals on the AlCNF support relative to alumina support. The BET surface area of Al—MoCo may be 75% less than Al-CNF-MoCo, e.g., 166 vs. 200 m.sup.2/g. SEM images indicate that the catalyst nanoparticles can be evenly distributed on the surface of the CNF. The surface area of the AlMoCoB5% may be 206 m.sup.2/g, which is higher than AlMoCoB0% and AlMoCoB2%, and AlMoCoB5% has the highest HDS activity, removing more than 98% sulfur and below allowed levels.

Carbon nanofiber doped alumina (Al-CNF) supported MoCo catalysts in hydrodesulfurization (HDS), and/or boron doping, e.g., up to 5 wt % of total catalyst weight, can improve catalytic efficiency. Al-CNF-supported MoCo catalysts, (Al-CNF-MoCo), can reduce the sulfur concentration in fuel, esp. liquid fuel, to below the required limit in a 6 h reaction time. Thus, Al-CNF-MoCo has a higher catalytic activity than Al—MoCo, which may be explained by higher mesoporous surface area and better dispersion of MoCo metals on the AlCNF support relative to alumina support. The BET surface area of Al—MoCo may be 75% less than Al-CNF-MoCo, e.g., 166 vs. 200 m.sup.2/g. SEM images indicate that the catalyst nanoparticles can be evenly distributed on the surface of the CNF. The surface area of the AlMoCoB5% may be 206 m.sup.2/g, which is higher than AlMoCoB0% and AlMoCoB2%, and AlMoCoB5% has the highest HDS activity, removing more than 98% sulfur and below allowed levels.

Provided is a method for preparing a diol. In the method, a saccharide and hydrogen as raw materials are contacted with a catalyst in water to prepare the diol. The employed catalyst is a composite catalyst comprised of a main catalyst and a cocatalyst, wherein the main catalyst is a water-insoluble acid-resistant alloy; and the cocatalyst is a soluble tungstate and/or soluble tungsten compound. The method uses an acid-resistant, inexpensive and stable alloy needless of a support as a main catalyst, and can guarantee a high yield of the diol in the case where the production cost is relatively low.

Provided is a method for preparing a diol. In the method, a saccharide and hydrogen as raw materials are contacted with a catalyst in water to prepare the diol. The employed catalyst is a composite catalyst comprised of a main catalyst and a cocatalyst, wherein the main catalyst is a water-insoluble acid-resistant alloy; and the cocatalyst is a soluble tungstate and/or soluble tungsten compound. The method uses an acid-resistant, inexpensive and stable alloy needless of a support as a main catalyst, and can guarantee a high yield of the diol in the case where the production cost is relatively low.

A fuel tank for storing a hydrogen liquid carrier and a spent hydrogen liquid carrier includes a substantially rigid exterior tank wall including a first chamber and a second chamber. The first chamber is fluidly disconnected from the second chamber, and the second chamber includes a dynamically expandable and contractible enclosure, the enclosure being configured to define a dynamic boundary between the hydrogen liquid carrier and spent hydrogen liquid carrier. The fuel tank also includes a first channel in flow communication with one of the first chamber or the second chamber and a second channel in flow communication with another of the first chamber or the second chamber, wherein the first channel and the second channel are flow connected such that a flow through one of the first or second channels is returned to the another of the first or second channels, and that during the flow, the dynamic boundary changes position causing a change in a volume of the second chamber.

An oxygen transfer agent comprising a metal-boron oxide is provided. The average oxidation state of the metal in the metal-boron oxide is about 3+, and has 10% or less of a stoichiometric excess in moles of Mn with respect to the boron. The oxygen transfer agent may further comprise a magnesia-phosphate cement. The oxygen transfer agent is capable of oxidatively dehydrogenating a hydrocarbon feed at reaction conditions to produce a dehydrogenated hydrocarbon product and water. The oxidative dehydrogenation can take place under reaction conditions of less than 1000 ppm weight molecular oxygen, or in the presence of more than 1000 ppm weight of molecular oxygen. Also provided are methods of using the oxygen transfer agents, and an apparatus for effecting the oxidative dehydrogenation of the hydrocarbon feed.

An oxygen transfer agent comprising a metal-boron oxide is provided. The average oxidation state of the metal in the metal-boron oxide is about 3+, and has 10% or less of a stoichiometric excess in moles of Mn with respect to the boron. The oxygen transfer agent may further comprise a magnesia-phosphate cement. The oxygen transfer agent is capable of oxidatively dehydrogenating a hydrocarbon feed at reaction conditions to produce a dehydrogenated hydrocarbon product and water. The oxidative dehydrogenation can take place under reaction conditions of less than 1000 ppm weight molecular oxygen, or in the presence of more than 1000 ppm weight of molecular oxygen. Also provided are methods of using the oxygen transfer agents, and an apparatus for effecting the oxidative dehydrogenation of the hydrocarbon feed.

A system for oxidative conversion of a mixed hydrocarbon feed stream to a product stream containing at least one olefin is provided. The system includes a plurality of reactors each capable of oxidatively dehydrogenating at least a portion of a hydrocarbon in the mixed hydrocarbon feed, and each reactor able to operate at different set of reaction conditions from other reactors in the plurality of reactors. All of the reactors use the same oxygen transfer agent to produce at least one olefin. In some embodiments, at least one reactor is optimized to oxidatively couple methane to produce ethylene, while other reactors are optimized to oxidatively dehydrogenate ethane to ethylene or to oxidatively dehydrogenate propane to ethylene and/or propylene. All of the reactors feed into a single regeneration unit for the oxygen transfer agent. A method of oxidatively converting the mixed hydrocarbon feed to an olefin is also provided.

A system for oxidative conversion of a mixed hydrocarbon feed stream to a product stream containing at least one olefin is provided. The system includes a plurality of reactors each capable of oxidatively dehydrogenating at least a portion of a hydrocarbon in the mixed hydrocarbon feed, and each reactor able to operate at different set of reaction conditions from other reactors in the plurality of reactors. All of the reactors use the same oxygen transfer agent to produce at least one olefin. In some embodiments, at least one reactor is optimized to oxidatively couple methane to produce ethylene, while other reactors are optimized to oxidatively dehydrogenate ethane to ethylene or to oxidatively dehydrogenate propane to ethylene and/or propylene. All of the reactors feed into a single regeneration unit for the oxygen transfer agent. A method of oxidatively converting the mixed hydrocarbon feed to an olefin is also provided.

Enhanced oxygen transfer agent systems and methods of use thereof are provided. According to one aspect, a method for producing olefins from a hydrocarbon feed includes the step of contacting a hydrocarbon feed comprised of one or more alkanes with an oxygen transfer agent at a temperature of 350° C. to 1000° C. The oxygen transfer agent includes an oxygen-donating chalcogen agent including at least one of S, Se, or Te and a reducible metal oxide. The chalcogen has an oxidation state greater than +2. A method for producing one or more olefins by partial combustion of a hydrocarbon feed is provided. The method includes partially combusting a hydrocarbon feed comprised of one or more alkanes by contacting the hydrocarbon feed with an oxygen transfer agent comprising CaSO.sub.4 at a temperature of 350° C. to 1000° C. to produce one or more olefins comprising ethylene and coproducing water.