The present invention relates to a method for producing unsaturated aldehydes and unsaturated carboxylic acids. According to the present invention, a method for producing unsaturated aldehydes and unsaturated carboxylic acids which can impart activity and control temperature independently in fixed catalyst layer zones in a shell-and-tube reactor, thereby exhibiting improved yield and operation stability, is provided.

The invention discloses a binder-free high strength and low steam-to-oil ratio ethylbenzene dehydrogenation catalyst, which is characterized by comprising the following components in percentage by weight: (a) 60-85% Fe.sub.2O.sub.3; (b) 3-25% K.sub.2O; (c) 0.1-5% MoO.sub.3; (d) 3-20% CeO.sub.2; (e) 0.1-5% CaO; (f) 0.1-5% Na.sub.2O; (g) 0.1-5% MnO.sub.2, wherein the weight ratio of sodium oxide to manganese dioxide is 0.1-10, and no binder is added during the preparation of the catalyst. The low steam-to-oil ratio ethylbenzene dehydrogenation catalyst provided by the present invention contains no binder and maintains high strength, and has high activity and stability at low steam-to-oil ratio.

A method for producing diene comprises a step 1 of obtaining a straight chain internal olefin by removing a branched olefin from a raw material including at least the branched olefin and a straight chain olefin; and a step 2 of producing diene from the internal olefin by oxidative dehydrogenation using a first catalyst and a second catalyst, and the first catalyst has a complex oxide including bismuth, molybdenum and oxygen, and the second catalyst includes at least one selected from the group consisting of silica and alumina.

Oxidative dehydrogenation is an alternative to the energy extensive steam cracking process presently used for the production of olefins from paraffins, but has not been implemented commercially partially due to the unstable nature of hydrocarbon/oxygen mixtures, and partially due to the cost involved in the construction of new facilities. An oxidative dehydrogenation chemical complex designed to reduce costs by including integration of an oxygen separation module that also addresses safety concerns and reduces emission of greenhouse gases is described.

Disclosed herein is a catalyst for producing biodiesel, including a carrier having water resistance and an active component supported on the carrier and used in a hydrotreating reaction or a decarboxylation reaction. Since the catalyst for producing biodiesel includes a carrier having strong water resistance, the deactivation of the catalyst due to the water produced through a process of producing HBD can be prevented, thus remarkably improving the long term stability of a catalyst.

The present invention relates to a method for preparing a catalyst which can produce carbon nanotubes having a higher bulk density by supporting a catalyst component under pressurized conditions, and to a method for producing carbon nanotubes using the catalyst so produced.

The present invention relates to a method for preparing a catalyst which can produce carbon nanotubes having a higher bulk density by supporting a catalyst component under pressurized conditions, and to a method for producing carbon nanotubes using the catalyst so produced.

A method may load granules into reaction tubes of a vertical multitube reactor installed vertically by dropping the granules from above each of the reaction tubes whereby a linear member is inserted and suspended in the reaction tube. The reaction tube has an effective length of ?1000 mm. The linear member includes a small-diameter portion positioned on an upper side and large-diameter portion continuously extending from the small-diameter portion. The small-diameter portion has an outer diameter (Ra) of ?5.0 mm, and the large-diameter portion has an outer diameter (Rb) of 5.0 to 15.0 mm larger than Ra. A length of the small-diameter portion from reaction tube's upper end is 10.0 mm or more. A distance between an upper surface of a granule loaded layer formed inside the reaction tube and a lower end of the linear member inserted in the reaction tube is ?100 mm.

The invention is concerned with a method for producing a conjugated diene including a reaction step of subjecting a raw material gas containing a monoolefin having a carbon atom number of 4 or more to an oxidative dehydrogenation reaction with a gas containing molecular oxygen in the presence of a catalyst, to obtain a reaction product gas containing a conjugated diene; and a cooling step of cooling the reaction product gas, wherein in the cooling step, a cooling agent is supplied into a cooling column and brought into contact with the reaction product gas; the cooling agent discharged from the cooling column is then cooled by a heat exchanger; a precipitate dissolved in the cooling agent is precipitated within the heat exchanger and recovered; and the cooling agent from which the precipitate has been recovered is circulated into the cooling column.

An integrated process for producing C3-C4 olefins or di-olefins including: contacting a hydrocarbon feed and a catalyst feed in a fluidized dehydrogenation reactor under conditions such that a product mixture is formed and the catalyst is at least partially deactivated; transferring the product mixture and the catalyst from the reactor to a cyclonic separation system under conditions such that the product mixture is converted to form a new product mixture and is separated from the catalyst; transferring at least a portion of the catalyst to a regenerator vessel and heating it in order to combust the coke deposited thereon; subjecting the catalyst to a conditioning step to form an oxygen-containing, at least partially reactivated catalyst; and transferring the partially reactivated catalyst back to the fluidized dehydrogenation reactor.