A temperature-controlling measure for a hydrogenation slurry bed reactor has three control points that are set from low to high: cold hydrogen is injected automatically when the system reaches control point 1; cold oil in injected automatically when the system reaches control point 2; each pressure relief is opened automatically when the system reaches control point 3. The pressure relief point is set before and/or after the circulation pump of the reactor if internal circulation is set in the reactor; the pressure relief point is set at the reactor bottom if the internal circulation is not set; at least one pressure relief valve is set at each pressure relief point.

The present invention relates to a process and apparatus for withdrawing polymer agglomerates from a fluidised bed polymerisation reactor, the polymerisation reactor comprising a bottom zone having a generally conical shape and no fluidisation grid. The agglomerates are withdrawn by using an agglomerate trap below the bottom zone. A value of a process variable indicative of the content of agglomerates in the agglomerate trap is measured and the opening time of the valves transferring polymer to and from the agglomerate trap is adjusted based on the measured value.

Systems are provided that permit temperature control of a catalyst bed for conversion of alcohols to fuel hydrocarbons by modulating the water content of the alcohol feed stream provided to the catalyst bed. In some embodiments a secondary catalyst bed is provided for the conversion of light hydrocarbons found in the initial hydrocarbon product to fuel hydrocarbons that are liquid at ambient temperature and pressure.

Incorporating into a fixed bed reactor for an exothermal reaction having a catalyst supported on a support having a thermal conductivity typically less than 30 W/mk within the reaction temperature control limits heat dissipative particles having a thermal conductivity of at least 50 W/mk less than 30 W/mk within the reaction temperature control limits helps control the temperature of the reactor bed.

A reactor layout for a process of methanol production from low quality synthesis gas, in which relatively smaller adiabatic reactors can be operated more efficiently, some of the inherent disadvantages of adiabatic reactors for methanol production are avoided. This is done by controlling the outlet temperature in the pre-converter by rapid adjustment of the recycle gas, i.e. by manipulating the gas hourly space velocity in the pre-converter.

A multi-stage dehydrogenation process including contacting, in a first stage, a feed stream comprising a hydrocarbon and steam with a dehydrogenation catalyst under dehydrogenation conditions to yield a first stage effluent, heating the first stage effluent, and contacting, in a second stage, the heated first stage effluent with a dehydrogenation catalyst under dehydrogenation conditions to yield a second stage effluent comprising a dehydrogenation product, wherein the first stage includes a first reactor and a second reactor arranged in parallel, and wherein the second stage includes a third reactor connected in series with the first reactor and the second reactor. A multi-stage dehydrogenation system for carrying out dehydrogenation is also provided.

The present invention relates to a process for producing 2-chloro-3,3,3-trifluoropropene, comprising the steps: i) providing a stream A comprising at least one chlorinated compound selected from the group consisting of 2,3-dichloro-1,1,1-trifluoropropane, 1,1,1,2,3-pentachloropropane, 1,1,2,3-tetrachloropropene and 2,3,3,3-tetrachloropropene; and ii) in an adiabatic reactor comprising a fixed bed composed of an inlet and an outlet, bringing said stream A into contact, in the presence or absence of a catalyst, with HF in order to produce a stream B comprising 2-chloro-3,3,3-trifluoropropene, characterized in that the temperature at the inlet of the fixed bed of said adiabatic reactor is between 300° C. and 400° C. and the longitudinal temperature difference between the inlet of the fixed bed and the outlet of the fixed bed of said reactor is less than 20° C.

A process for producing 2,3,3,3-tetrafluoropropene comprises the steps: i) in a first adiabatic reactor comprising a fixed bed composed of an inlet and an outlet, bringing 2-chloro-3,3,3-trifluoropropene into contact with hydrofluoric acid in the gas phase in the presence of a catalyst to produce a stream A comprising 2,3,3,3-tetrafluoropropene, HF and unreacted 2-chloro-3,3,3-trifluoropropene; and ii) in a second adiabatic reactor comprising a fixed bed composed of an inlet and an outlet, bringing hydrofluoric acid into contact in the gas phase, optionally in the presence of a catalyst, with at least one chlorinated compound to produce a stream B comprising 2-chloro-3,3,3-trifluoropropene. The stream A obtained in step i) feeds said second reactor. The inlet temperature of the fixed bed of one of said first or second reactors is between 300° C. and 400° C. The longitudinal temperature difference between the inlet and the outlet of the fixed bed in question is less than 20° C.

A method for carrying out catalytic gas phase reactions including providing a tube bundle reactor which has a bundle of reaction tubes that are filled with a catalyst charge and are cooled by a heat transfer medium, conveying a reaction gas through the catalyst charge, the reaction gas flowing into each reaction tube divided into two part flows introduced in the axial direction of the reaction tube at different points in the catalyst charge the catalyst charge has at least two catalyst layers of different activity, wherein the activity of the first catalyst layer, in the flow direction of the reaction gas, is lower than the activity of the at least one other catalyst layer and in step a first part flow is introduced into the first catalyst layer and each further part flow is introduced past the first catalyst layer into the at least one further catalyst layer.

The present invention relates to a process for producing 2,3,3,3-tetrafluoropropene, comprising the steps: i) providing a stream A comprising at least one starting compound selected from the group consisting of 2-chloro-3,3,3-trifluoropropene and 2,3-dichloro-1,1,1-trifluoropropane; and ii) in an adiabatic reactor comprising a fixed bed composed of an inlet and an outlet, bringing said stream A into contact, in the presence or absence of a catalyst, with HF in order to produce a stream B comprising 2,3,3,3-tetrafluoropropene, characterized in that the temperature at the inlet of the fixed bed of said adiabatic reactor is between 300° C. and 400° C. and the longitudinal temperature difference between the inlet of the fixed bed and the outlet of the fixed bed of said reactor is less than 20° C.