The present invention provides a process for the preparation of ethene by vapour phase chemical dehydration of ethanol using an adiabatic reactor, wherein the interior of the adiabatic reactor is separated into at least three reaction zones, comprising a first reaction zone, at least one intermediate reaction zone and a final reaction zone, and wherein each zone contains an ethanol dehydration catalyst; said process comprising the steps of; a) feeding a pre-heated reactant feed-stream into an inlet of the first reaction zone; b) extracting an effluent-stream from an outlet of the first reaction zone; c) feeding said effluent-stream into an inlet of a subsequent intermediate reaction zone; d) extracting an effluent-stream from an outlet of the intermediate reaction zone; e) repeating steps (c) and (d) for any subsequent intermediate reaction zones, if present; f) feeding, into an inlet of the final reaction zone, the effluent-stream from the preceding intermediate reaction zone; g) extracting a product stream from an outlet of the final reaction zone; wherein the effluent-streams are re-heated prior to being fed into a subsequent reaction zone by means of one or more heat exchangers and; and wherein a single heat exchanger simultaneously re-heats at least two of the effluent-streams, such that no more than one heat exchanger is present for every two effluent-streams being re-heated in the process.

The present invention relates to a plant and a process for producing propylene at least one oxygenate, comprising a reactor for converting the reactant mixture into a product mixture which comprises propylene and also aliphatic and aromatic C.sub.5+ hydrocarbons, at least one distillation column for removing a C.sub.5+ stream, the C.sub.5+ stream comprising at least 90 wt % of the aliphatic and aromatic C.sub.5+ hydrocarbons of the product mixture, an extractive distillation column for separating the C.sub.5+ stream into an aromatics stream and an aliphatics stream, the aliphatics stream comprising at least 90 wt % of the aliphatics of the C.sub.5+ stream, and the aromatics stream comprising at least 90 wt % of the aromatics of the C.sub.5+ stream, and an aliphatics recycle line for at least partial recycling of the aliphatics stream to the reactor. According to the invention, an aromatics recycle line is provided which returns the aromatics stream at least partially as extractant into the extractive distillation column.

Methods and systems for heating a reactor feed in a multi reactor hydrocarbon dehydrogenation process. The methods and systems are advantageously employed for the production of styrene by the catalytic dehydrogenation of ethylbenzene. The catalytic dehydrogenation process employs heating steam operating at a steam to oil ratio of about 1.0 or less and relatively low steam superheater furnace temperature, such that all components exposed to steam in the process (outside of the fired heaters) can be constructed with standard metallurgy.

A device and a process for producing undecylenic acid methyl ester using methyl ricinoleate as raw material are provided. The device comprises a feed pump, a raw material pre-heater, a microwave catalytic reactor, a microwave generator, a temperature controller and an infrared sensor, a condenser, a product tank and a discharge pump. The feed pump is connected with the raw material pre-heater, which is connected with the inlet of the microwave catalytic reactor. The outlet of the microwave catalytic reactor is connected with the condenser, which is connected to the product tank and the discharge pump. The microwave catalytic reactor is located in the microwave generator, which is connected with the temperature controller and the infrared sensor. The process is as follows: high-purity methyl ricinoleate, used as the raw material, is converted to methyl undecene and heptaldehyde by microwave-assisted pyrolysis process, followed by isolation and purification to produce methyl undecene.

A catalyst for selectively oxidizing hydrogen sulfide to element sulfur, catalyst for burning tail-gas, and process for deeply catalytically oxidizing hydrogen sulfide to sulfur are disclosed. The catalyst for selectively oxidizing hydrogen sulfide to element sulfur is prepared by: 10-34% of iron trioxide and 60-84% of anatase titanium dioxide, and the balance being are auxiliary agents. Also a catalyst for burning tail-gas is prepared by: 48-78% of iron trioxide and 18-48% of anatase titanium dioxide, and the balance being auxiliary agents. The catalyst of the present invention has high selectivity and high sulfur recovery rate. An isothermal reactor and an adiabatic reactor of the present invention are connected in series and are filled with the above two catalysts for reactions, thus reducing total sulfur in the vented gas while having a high sulfur yield and conversion rate.

A trickle bed reactor, comprising a plurality of catalyst beds connected in series and progressively increasing in catalyst mass in a direction from upstream to downstream; and a plurality of heat exchangers, wherein each of the heat exchangers is located between two of the plurality of catalyst beds, and wherein each of the heat exchangers does not exchange heat with an outer surface of a vessel that contains any of the catalyst beds.

The invention is concerned with the issue of how to produce n-pentanal by hydroformylation from feedstock mixtures comprising a small proportion of n-butene and a large proportion of n-butane. Specifically, solutions for further optimizing established processes for hydroformylation of such low-butene mixtures in terms of material utilization are sought. The present invention has for its object to enhance the material utilization of the feedstock mixture in the production of n-pentanal from feedstock mixtures having a small proportion of n-butene and a large proportion of n-butane. The process shall be capable of economic operation on an industrial scale. In particular an existing oxo plant shall be honed to achieve better raw material utilization. This object is achieved by a combination of a hydroformylation and a dehydrogenation, wherein said combination has the special feature that the dehydrogenation is arranged after the hydroformylation in the downstream direction and is thus markedly smaller than conventional dehydrogenations provided upstream. A skillful product removal effectively removes contaminants formed in the process.

A system for continuously treating recycled polymeric material includes a hopper configured to feed the recycled polymeric material into the system. An extruder can turn the recycled polymeric material in a molten material. In some embodiments, the extruder uses thermal fluids, electric heaters, and/or a separate heater. The molten material is depolymerized in a reactor. In some embodiments, a catalyst is used to aid in depolymerizing the material. In certain embodiments, the catalyst is contained in a permeable container. The depolymerized molten material can then be cooled via a heat exchanger. In some embodiments, multiple reactors are used. In certain embodiments, these reactors are connected in series. In some embodiments, the reactor(s) contain removable static mixer(s) and/or removable annular inserts.

An ethylbenzene dehydrogenation plant for producing styrene which comprises a reaction section in which one or more adiabatic reaction apparatuses are positioned in series, and a steam circuit in which there is at least one first steam heat exchange apparatus; said plant being characterized in that it comprises heating equipment in which there is a heating circuit by means of recirculation of the fumes formed during dehydrogenation processes of ethylbenzene to give styrene, wherein said heating equipment comprises the following apparatuses in fluid communication with each other by means of said heating circuit: one or more ultra-heating apparatuses, one or more combustion devices in which at least one steam diffuser, one burner and at least one mixing apparatus are inserted, one or more ventilation device(s).

A system for reducing dioxygen (O.sub.2) present in vapors from oil storage tanks. The system may include an inlet that receives vapors from the tanks; a heating device coupled with the inlet that heats vapors to a first temperature to form heated vapor; and a vessel coupled receiving heated vapor and containing at least one catalyst to reduce dioxygen from the heated vapor. The catalyst may include palladium, and the vessel may include zinc oxide to remove sulfur from the heated vapor. A compressor may be used to compress the vapors. A controller may be provided to monitor O.sub.2 concentration in heated vapor, and the controller directs flow of heated vapor to a gas pipeline if the O.sub.2 concentration is below a predetermined level; or if the O.sub.2 concentration is unacceptably high, the controller directs flow of vapor to be re-circulated within the system to further reduce O.sub.2 concentration therein.