摘要:
Novel redox based systems for fuel and chemical production with in-situ CO2 capture are provided. A redox system using one or more chemical intermediates is utilized in conjunction with liquid fuel generation via indirect Fischer-Tropsch synthesis, direct hydrogenation, or pyrolysis. The redox system is used to generate a hydrogen rich stream and/or CO2 and/or heat for liquid fuel and chemical production. A portion of the byproduct fuels and/or steam from liquid fuel and chemical synthesis is used as part of the feedstock for the redox system.
摘要:
A process for producing hydrogen, comprising the steps of: (a) gasifying a fuel into a raw synthesis gas comprising CO, hydrogen, steam and sulfur and halide contaminants in the form of H2S, COS and HX, where X is a halide; (b) passing the raw synthesis gas through a water gas shift reactor (WGSR) into which CaO and steam are injected, the CaO reacting with the shifted gas to remove CO2, sulfur and halides in a solid-phase calcium-containing product comprising CaCO3, CaS and CaX2; (c) separating the solid-phase calcium-containing product from an enriched gaseous hydrogen product; and (d) regenerating the CaO by calcining the solid-phase calcium-containing product at a condition selected from the group consisting of: in the presence of steam, in the presence of CO2, in the presence of synthesis gas, in the presence of H2 and O2, under partial vacuum, and combinations thereof. The CaO may have a surface area of at least 12.0 m2/g and a pore volume of at least 0.015 cm3/g, the CaO having a sorption capacity of at least about 70 grams of CO2 per kilogram of CaO.
摘要:
Methods of making silicon carbide comprise providing at least one organosilicon precursor material, hydrolyzing the organosilicon in a solution comprising water and an acid catalyst, providing a surfactant to the solution, forming a gel by adding a base to the solution, and heating the gel at a temperature and for a time sufficient to produce silicon carbide.
摘要:
A reaction-based process has been developed for the selective removal of carbon dioxide (CO2) from a multicomponent gas mixture to provide a gaseous stream depleted in CO2 compared to the inlet CO2 concentration in the stream. The proposed process effects the separation of CO2 from a mixture of gases (such as flue gas/fuel gas) by its reaction with metal oxides (such as calcium oxide). The Calcium based Reaction Separation for CO2 (CaRS-CO2) process consists of contacting a CO2 laden gas with calcium oxide (CaO) in a reactor such that CaO captures the CO2 by the formation of calcium carbonate (CaCO3). Once “spent”, CaCO3 is regenerated by its calcination leading to the formation of fresh CaO sorbent and the evolution of a concentrated stream of CO2. The “regenerated” CaO is then recycled for the further capture of more CO2. This carbonation-calcination cycle forms the basis of the CaRS-CO2 process. This process also identifies the application of a mesoporous CaCO3 structure, developed by a process detailed elsewhere, that attains >90% conversion over multiple carbonation and calcination cycles. Lastly, thermal regeneration (calcination) under vacuum provided a better sorbent structure that maintained reproducible reactivity levels over multiple cycles.
摘要翻译:已经开发了一种基于反应的方法,用于从多组分气体混合物中选择性除去二氧化碳(CO 2 H 2),以提供与CO 2 CO 2相比耗尽的气流, 流中的入口CO 2 H 2浓度。 所提出的方法通过与金属氧化物(例如氧化钙)的反应来影响CO 2 CO 2从气体(例如烟道气/燃料气体)的混合物中的分离。 用于CO 2(CaS 2 CO 2)工艺的基于钙的反应分离包括将含CO 2的气体与氧化钙(CaO)接触, 在反应器中使得CaO通过形成碳酸钙(CaCO 3)而捕获CO 2。 一旦“消耗”,CaCO 3 3通过其煅烧再生,导致新鲜的CaO吸附剂的形成和CO 2的浓缩物流的逸出。 然后将“再生的”CaO再循环以进一步捕获更多的CO 2。 该碳酸化煅烧循环形成CaRS-CO 2 N 2工艺的基础。 该方法还确定了通过其他地方详细描述的方法开发的介孔CaCO 3 3结构的应用,其通过多次碳酸化和煅烧循环达到> 90%的转化率。 最后,在真空下的热再生(煅烧)提供了更好的吸附剂结构,其在多个循环中保持可重复的反应性水平。
摘要:
A method for producing hydrogen gas is provided and comprises reducing a metal oxide in a reduction reaction between a carbon-based fuel and a metal oxide to provide a reduced metal or metal oxide having a lower oxidation state, and oxidizing the reduced metal or metal oxide to produce hydrogen and a metal oxide having a higher oxidation state. The metal or metal oxide is provided in the form of a porous composite of a ceramic material containing the metal or metal oxide. The porous composite may comprise either a monolith, pellets, or particles.
摘要:
Methods and systems for sequestering carbon dioxide and generating hydrogen are disclosed. In some embodiments, the methods include the following: dissolving an iron based material that includes a carbonate-forming element into a solution including the carbonate-forming element and iron; increasing a pH of the solution to cause precipitation of iron oxide from the solution thereby generating a first source of Fe2O3; reacting the carbonate-forming element in the solution with a first source of carbon dioxide to produce a carbonate thereby sequestering the carbon dioxide; oxidizing the first source of Fe2O3 with a carbonaceous fuel thereby generating a second source of carbon dioxide and iron; and oxidizing the iron with steam thereby generating hydrogen and an iron oxide. Some embodiments include producing iron-based catalysts.
摘要翻译:公开了用于隔离二氧化碳和产生氢的方法和系统。 在一些实施方案中,所述方法包括:将包含碳酸酯形成元素的铁基材料溶解到包含碳酸酯形成元素和铁的溶液中; 增加溶液的pH使溶液中的氧化铁沉淀,从而产生第一Fe 2 O 3源; 使溶液中的碳酸酯形成元素与第一二氧化碳源反应以产生碳酸盐,从而螯合二氧化碳; 用碳质燃料氧化第一来源的Fe 2 O 3,从而产生第二二氧化碳和铁源; 并用蒸汽氧化铁,从而产生氢气和氧化铁。 一些实施方案包括生产铁基催化剂。
摘要:
A process for the efficient capture of CO2 and sulfur from combustion flue gas streams and gasification based fuel gas mixtures using regenerable and recyclable calcium based sorbents. The regeneration of the calcium sorbent is accomplished by hydrating the sorbent at high temperatures of about 600° C. and a pressure higher than 6 bars to lower the parasitic energy consumption.
摘要:
A process for producing hydrogen, comprising the steps of: (a) gasifying a fuel into a raw synthesis gas comprising CO, hydrogen, steam and sulfur and halide contaminants in the form of H2S, COS and HX, where X is a halide; (b) passing the raw synthesis gas through a water gas shift reactor (WGSR) into which CaO and steam are injected, the CaO reacting with the shifted gas to remove CO2, sulfur and halides in a solid-phase calcium-containing product comprising CaCO3, CaS and CaX2; (c) separating the solid-phase calcium-containing product from an enriched gaseous hydrogen product; and (d) regenerating the CaO by calcining the solid-phase calcium-containing product at a condition selected from the group consisting of: in the presence of steam, in the presence of CO2, in the presence of synthesis gas, in the presence of H2 and O2, under partial vacuum, and combinations thereof. The CaO may have a surface area of at least 12.0 m2/g and a pore volume of at least 0.015 cm3/g, the CaO having a sorption capacity of at least about 70 grams of CO2 per kilogram of CaO.
摘要:
A method for mineral sequestration of pollutant gases resulting from the combustion of carbon-based fuels such as carbon and sulfur dioxides is provided and includes, providing a particulate magnesium-containing mineral and exposing the magnesium-containing mineral to a weak acid to dissolve magnesium from the mineral and form a magnesium-containing solution. The surface of the particulate magnesium-containing mineral is physically activated to expose and dissolve additional magnesium into the solution. Pollutant gases such as carbon dioxide are mixed with the magnesium-containing solution. When the pH of the magnesium-containing solution is increased, solid magnesium carbonate is formed.