A process for preparing C2 to C3 hydrocarbons may include introducing a feed stream including hydrogen gas and a carbon-containing gas comprising carbon monoxide, carbon dioxide, and mixtures thereof into a reaction zone of a reactor, and converting the feed stream into a product stream comprising C2 to C3 hydrocarbons in the reaction zone in the presence of a hybrid catalyst. The hybrid catalyst may include a metal oxide catalyst component and a microporous catalyst component comprising 8-MR pore openings less than or equal to 5.1 A and a cage defining ring size less than or equal to 7.45 A, where a C2/C3 carbon molar ratio of the product stream is greater than or equal to 0.7.

A process for preparing C2 to C3 hydrocarbons may include introducing a feed stream including hydrogen gas and a carbon-containing gas comprising carbon monoxide, carbon dioxide, and mixtures thereof into a reaction zone of a reactor, and converting the feed stream into a product stream comprising C2 to C3 hydrocarbons in the reaction zone in the presence of a hybrid catalyst. The hybrid catalyst may include a metal oxide catalyst component and a microporous catalyst component comprising 8-MR pore openings less than or equal to 5.1 A and a cage defining ring size less than or equal to 7.45 A, where a C2/C3 carbon molar ratio of the product stream is greater than or equal to 0.7.

Disclosed are a catalyst for preparing a synthetic gas through dry reforming, a method preparing the catalyst, and a method using the catalyst for preparing the synthetic gas. The catalyst may include: a support including regularly distributed mesopores; metal nanoparticles supported on the support; and a metal oxide coating layer coated on a surface of the support.

The present invention features a direct synthesis of light olefins through the hydrogenation of carbon dioxide. In.sub.2O.sub.3 supported on cubic phase yttria-stabilized zirconia is used as a catalyst and is mixed with a molecular sieve to perform the hydrogenation. The cubic crystal structure of the yttria-stabilized zirconium dioxide is an excellent support for indium oxide particles and prevents their deactivation during CO.sub.2 hydrogenation. This direct synthesis route promotes a stable and efficient method for producing light olefins.

The present invention features a direct synthesis of light olefins through the hydrogenation of carbon dioxide. In.sub.2O.sub.3 supported on cubic phase yttria-stabilized zirconia is used as a catalyst and is mixed with a molecular sieve to perform the hydrogenation. The cubic crystal structure of the yttria-stabilized zirconium dioxide is an excellent support for indium oxide particles and prevents their deactivation during CO.sub.2 hydrogenation. This direct synthesis route promotes a stable and efficient method for producing light olefins.

A fluidized catalytic reactor connected to a start-up heater is provided. The start-up heater provides sufficient heat to a catalyst containing stream to gradually increase the feed temperature. This allows for a critical volumetric flow rate to be achieved so that catalyst can be recovered from product instead of being entrained in product.

A process for preventing hazardous conditions at startup and shutdown of a reactor by sending an inert gas such as nitrogen to strip entrained oxygen from the catalyst when reactor temperatures are below about 240° C. During normal operation the entrained oxygen reacts with hydrocarbons to produce oxides but at the lower temperatures that are present at startup or shutdown these reactions do not occur sufficiently leaving oxygen that can cause hazardous conditions as temperatures increase upon startup. When the temperature is in the safe operating zone above 240° C., the nitrogen gas is stripped by air or other oxygen containing gas.

A process for preventing hazardous conditions at startup and shutdown of a reactor by sending an inert gas such as nitrogen to strip entrained oxygen from the catalyst when reactor temperatures are below about 240° C. During normal operation the entrained oxygen reacts with hydrocarbons to produce oxides but at the lower temperatures that are present at startup or shutdown these reactions do not occur sufficiently leaving oxygen that can cause hazardous conditions as temperatures increase upon startup. When the temperature is in the safe operating zone above 240° C., the nitrogen gas is stripped by air or other oxygen containing gas.

Disclosed are a catalyst for preparing hydrocarbons from carbon dioxide by one-step hydrogenation and a method for preparing same. The catalyst includes nano-metal oxides and hierarchical zeolites, where the mass fraction of the nano-metal oxides in the catalyst is 10%-90%, and the mass fraction of the hierarchical zeolites in the catalyst is 10%-90%. The catalyst has excellent catalytic performance, good reaction stability and high selectivity for desired products, and in the hydrocarbons, C.sub.2.sup.=-C.sub.4.sup.= reach up to 80%, C.sub.5+ reach up to 80%, and aromatics reach up to 65%.

Disclosed are a catalyst for preparing hydrocarbons from carbon dioxide by one-step hydrogenation and a method for preparing same. The catalyst includes nano-metal oxides and hierarchical zeolites, where the mass fraction of the nano-metal oxides in the catalyst is 10%-90%, and the mass fraction of the hierarchical zeolites in the catalyst is 10%-90%. The catalyst has excellent catalytic performance, good reaction stability and high selectivity for desired products, and in the hydrocarbons, C.sub.2.sup.=-C.sub.4.sup.= reach up to 80%, C.sub.5+ reach up to 80%, and aromatics reach up to 65%.