Methods for determining ethylene concentration in an ethylene oligomerization reactor using an ultrasonic flow meter are described, and these methods are integrated into ethylene oligomerization processes and related oligomerization reactor systems.

A method and system for membrane-assisted production of high purity concentrated dimethyl carbonate by the reaction of carbon dioxide and methanol is provided. Carbon dioxide is recovered from flue gas or other dilute streams from industrial processes by a membrane and subsequent conversion takes place to an intermediate methyl carbamate by reacting of carbon dioxide with ammonia and methanol. For high-purity carbon dioxide obtained by one of the carbon capture technologies or by a process (such as, for example, ethanol fermentation process) the membrane reactor is replaced with a catalytic reactor for direct conversion of carbon dioxide to methyl carbamate by reacting with ammonia and methanol. The methyl carbamate is further reacted with methanol for conversion to dimethyl carbonate. An integrated reactive distillation process using side reactors is used for facilitating the catalytic reaction in the subject method for producing high purity dimethyl carbonate.

A process for the catalytic oxidation of ammonia, comprising: passing an ammonia-containing gas, in the presence of oxygen, over a catalyst contained in a reactor, obtaining a process gas containing nitrogen oxides, and cooling said process gas with a heat exchanger accommodated in the reactor, wherein a portion of said process gas, located in the shell side, bypasses the heat exchanger and forms a hot current which mixes with cooled gas downstream the heat exchanger, and the bypass is regulated on the basis of a target outlet temperature of the mixed process gas.

Provided is a graphene production method using Joule heating, including: a catalytic metal placement step in which a catalytic metal is disposed on a pair of electrodes disposed inside a chamber; a gas supply step in which a carbon-containing reaction gas and a carrier gas for transporting the reaction gas are supplied into the chamber; a heating step in which the catalytic metal is rapidly heated to a temperature required for synthesis of graphene; a temperature maintenance step in which the temperature of the catalytic metal is maintained to form the graphene on the catalytic metal; and a cooling step in which the catalytic metal is cooled to prevent local occurrence of hotspots on the graphene formed on the catalytic metal, wherein the heating step, the temperature maintenance step, and the cooling step constitute one cycle of temperature control and the cycle is repeated for a predetermined process time.

A process for commencing a continuous reaction in a reactor system includes introducing a catalyst to a catalyst processing portion of the reactor system, the catalyst initially having a first temperature of 500 C or less, and contacting the catalyst at the first temperature with a commencement fuel gas stream, which includes at least 80 mol % commencement fuel gas, in the catalyst processing portion. Contacting of the catalyst with the commencement fuel gas stream causes combustion of the commencement fuel gas. The process includes maintaining the contacting of the catalyst with the commencement fuel gas stream until the temperature of the catalyst increases from the first temperature to a second temperature at which combustion of a regenerator fuel source maintains an operating temperature range in the catalyst processing portion.

A process and system for the conversion of a feedstock comprising C3-C5 light alkanes to a C5+ hydrocarbon product, for example, a BTX-rich hydrocarbon product, by performing the alkane activation (first-stage) and the oligomerization/aromatization (second-stage) in separate stages, which allows each conversion process to occur at optimal reaction conditions thus increasing the overall hydrocarbon product yield. The alkane activation or first-stage is operated at a higher temperature than the second-stage since light alkanes are much less reactive than light olefins. Since aromatization of olefins is more efficient at higher pressure, the second-stage is maintained at a higher pressure than the first-stage. Further, fixed-bed catalysts are used in each of the first-stage and the second-stage.

Disclosed are systems, servers and methods for improving temperature profile control in a reactor with at least three fixed beds, exothermic reactions and interstage cooling. A model of the temperature differential across the first bed is developed and its error is used to infer unmeasured feed composition disturbances, which are used in the control of the downstream fixed beds for faster response to unmeasured feed composition changes and improved control of the temperature profile throughout the reactor. The first bed model error is then used as an input into an overall model that predicts reactor temperature profiles, which provides advanced notice of reactions in downstream beds, and enables efficient adjustment and compensation to a feed composition change. A Model Predictive Control (MPC) algorithm is applied to adjust the bed intercooling and first bed feed temperature so that the reactor temperature profile can be more precisely controlled.

The present invention describes a processes, systems, and catalysts for the utilization of carbon dioxide into high quality synthesis gas that can then be used to produce fuels (e.g., diesel fuel) and chemicals. In one aspect, the present invention provides a process for the conversion of a feed gas comprising carbon dioxide and hydrogen to a product gas comprising carbon monoxide and water.

Provided is a propylene oxide production apparatus including a switching mechanism that is capable of switching a state of each reactor between an operating state where reaction raw materials are supplied and an epoxidation reaction is performed and a non-operating state where the supply of the reaction raw materials is shut off. The propylene oxide production apparatus is capable of changing a reactor in the non-operating state one by one, and performs switching in such a way that only reactors in the operating state are connected fluidically in series or in parallel, thereby enabling supplying the reaction raw materials to the reactors in the operating state. A sampling mechanism is also provided that samples part of the reaction mixture from each discharge line that is connected to each reactor.

The present disclosure provides systems and methods for processing ammonia. The system may comprise one or more reactor modules configured to generate hydrogen from a source material comprising ammonia. The hydrogen generated by the one or more reactor modules may be used to provide additional heating of the reactor modules (e.g., via combustion of the hydrogen), or may be provided to one or more fuel cells for the generation of electrical energy.