A method for preparing hydrogen from ammonia by using pressure swing adsorption (PSA) is provided. The method for preparing hydrogen from ammonia, of the present invention, comprises the steps of: generating hydrogen and nitrogen from ammonia gas through a high-temperature reaction by using a catalyst; performing purification by selectively adsorbing unreacted ammonia gas from a gas containing unreacted ammonia and low-purity hydrogen and nitrogen, which are supplied through the high-temperature reaction and cooled; and performing purification by separating high-purity hydrogen from the gas consisting of low-purity hydrogen and nitrogen, wherein purification is carried out by using a carbon molecular sieve (CMS) adsorbent so as to desorb the unreacted ammonia gas through PSA.

A system for producing an organic substance, including: a synthesis gas generation furnace for producing a synthesis gas by partially oxidizing a waste including a carbon source; a synthesis gas purification unit connected to the synthesis gas generation furnace and purifying the synthesis gas generated in the synthesis gas generation furnace to reduce an impurity concentration in the synthesis gas; and an organic substance synthesis unit which is connected to the synthesis gas purification unit and generates an organic substance from the synthesis gas purified in the synthesis gas purification unit, wherein the synthesis gas purification unit includes a detection unit for measuring an impurity concentration in the synthesis gas.

The invention concerns a process and apparatus for cracking ammonia in which heated ammonia gas at super-atmospheric pressure is partially cracked catalytically in an adiabatic reaction unit to produce partially cracked ammonia gas which is heated and fed to catalyst-containing reactor tubes in a furnace to cause cracking of further ammonia and produce a cracked gas comprising hydrogen gas, nitrogen gas and residual ammonia gas. At least some, preferably all, of the duty required to heat the partially cracked ammonia gas is provided by heat exchange with the cracked gas, enabling more efficient heat integration within the process.

The invention concerns a process and apparatus for cracking ammonia in which heated ammonia gas at super-atmospheric pressure is partially cracked in at least two adiabatic reactors in series with interstage heating in which the feed temperature to a first reactor is higher than the feed temperature to a further reactor to produce a partially cracked ammonia gas which is then fed to catalyst-containing reactor tubes in a furnace to produce a cracked gas comprising hydrogen gas, nitrogen gas and residual ammonia gas. The use of the adiabatic reactors enables more efficient heat integration within the process and the higher temperature in the first reactor enables the use of a nickel-based catalyst in that reactor as an alternative solution to the potential problem of the presence of oil in the ammonia.

The present invention concerns a process for cracking ammonia comprising providing an ammonia-containing feed gas at a temperature of over 600? C. and a pressure in a range from about 5 bar to about 50 bar; combusting a fuel with an oxidant gas in a furnace to heat reactor tubes to achieve a maximum inner wall temperature of over 700? C. and produce a flue gas, each reactor tube comprising a catalyst bed comprising a first row transition metal-based catalyst; and feeding the ammonia-containing feed gas to the reactor tubes to produce a cracked gas at a temperature of over 600? C. on exit from the reactor tubes.

The present invention relates, in general, to systems and methods for generating hydrogen from ammonia on-board vehicles, where the produced hydrogen is used as fuel source for an internal combustion engine. The present invention utilizes an electric catalyst unit operating in series with a heat exchange catalyst unit. The electric catalyst unit is used to initiate an ammonia cracking process on-board during a cold start or low load operating condition of the internal combustion engine, where the ammonia cracking process occurs in the heat exchange catalyst unit once exhaust gas from the internal combustion engine has been heated to a threshold temperature suitable to perform the ammonia cracking process.

Systems and methods are provided for performing ammonia cracking as the endothermic reaction step of a reaction cycle in a cyclic reaction environment, such as a reverse flow reaction environment. In such aspects, heat for the endothermic reaction can be provided by direct heating during a regeneration step. Optionally, the fuel for the regeneration step can correspond to additional ammonia and/or can include hydrogen generated during the ammonia cracking reaction step. Optionally, a selective catalytic reduction (SCR) zone can be included as part of the reactor, to reduce or minimize the amount of nitrogen oxides in the regeneration effluent from the reactor.

A system and a process for CO.sub.2 shift is provided. The system comprises a Reverse Water Gas Shift (RWGS) reactor, and a heat exchange reactor, HER. A first feed is converted in the RWGS reactor into a first product stream comprising CO. A second feed is arranged to be fed to a process side of the HER. At least a portion of the first product stream is arranged to be fed to a heating side of the HER such that heat from the first product stream is transferred to the process side of the HER, thereby allowing the conversion of the second feed to a second product stream comprising CO in the process side of the HER.

The present technology relates to a heat exchange reactor (HER) system comprising a first gas feed and a heat exchange reactor, HER. The HER has two reaction zones; a first reaction zone (I) arranged to carry out an overall exothermic reaction of the first gas feed, and a second reaction zone (II) arranged to carry out an overall endothermic reaction of gas from said first reaction zone (I).

A multi-stage shift reactor includes a vessel having an inner chamber configured to contain a first shift catalyst, the first shift catalyst configured to receive anode exhaust gas form a fuel cell and to output a first shifted gas, and an outer chamber annularly disposed about the inner chamber and configured to contain a second shift catalyst, the second shift catalyst configured to receive the first shifted gas and output a second shifted gas. The shift reactor further includes a water injection port downstream from the inner chamber and packing between the water injection port and the outer chamber, the packing configured to prevent liquid water from passing therethrough.