Nippon Shokubai Co., Ltd.

Michio Tanimoto

Hiromi Yunoki

Daisuke Nakamura

Tatsuya Kawajiri

Hideo Onodera

Nobuyuki Hakozaki

Yukio Aoki

Naomasa Kimura

Hideyuki Hironaka

Harunori Hirao

Osamu Dodo

Ikuo Kurimoto

Masakatsu Mori

Kazuyuki Uekawa

Yukihiro Matsumoto

Takeshi Nishimura

Tsukasa Takahashi

Hiroto Kasuga

Masaaki Okuno

Naohiro Fukumoto

Masatsugu Kitaura

Hideto Hashiba

Yasushi Kiyooka

Tadashi Sento

Masatsuga Kitaura

Shin-yuki Masaki

Tsuyoshi Kudoh

Ichiro Mihara

Shin-Yuki Masaki

The disclosed invention is a method for manufacturing an oxidized organic compound which includes a step of forming an oxidized organic compound, in use of a fixed-bed reactor having a reaction tube packed with an oxide catalyst, by supplying at least one type of organic compound as a reaction feedstock gas and using a molecular oxygen-containing gas to carry out a catalytic gas-phase oxidation reaction; and a step of stopping the catalytic gas-phase oxidation reaction. In the manufacturing method, when stopping the catalytic gas-phase oxidation reaction, the supply of the reaction feedstock gas is stopped, after which an inert gas is supplied to the reactor, then a molecular oxygen-containing gas is supplied, subsequent to which the supply of the molecular oxygen-containing gas to the reactor is stopped.

Oxidized organic compound manufacturing method

A fixed-bed reactor containing a first catalyst layer filled with a first catalyst for producing acrolein from propylene; a second catalyst layer filled with a second catalyst for producing acrylic acid from acrolein; and an inert substance layer provided between the first catalyst layer and the second catalyst layer, and filled with an inert substance of a cylindrical shape having a surrounding wall in which an opening is formed. A process for producing acrylic acid containing the step of producing acrylic acid from propylene by using the aforementioned fixed-bed reactor.

Fixed-bed reactor and process for producing acrylic acid using the reactor

An object of the present invention is to provide: a catalyst for production of acrylic acid which is a catalyst usable for production of acrylic acid and is excellent in the catalytic performances such as catalytic activity and in the physical properties such as physical strength of the catalyst itself; and a process for production of acrylic acid using this catalyst. As a means of achieving this object, a catalyst for production of acrylic acid according to the present invention is a catalyst obtained by drying a mixed liquid of starting materials including molybdenum and vanadium as essential components to give a dried material, molding the dried material with a liquid binder, and calcining the resultant molding, with the catalyst being characterized in that an ignition loss ratio of the dried material is from 5 to 40% by mass. A process for production of acrylic acid according to the present invention comprises the step of: subjecting acrolein to a catalytic gas phase oxidation in the presence of a molecular oxygen, with the process being characterized in that the above catalyst for production of acrylic acid according to the present invention is used.

Catalyst and process for production of acrylic acid

In industrial scale production of acrolen and/or acrylic acid by catalytic gas-phase oxidation of propylene or a propylene-containing gas with molecular oxygen or a molecular oxygen-containing gas or in industrial scale production of acrylic acid by catalytic gas-phase oxidation of acrolein or an acrolein-containing gas with molecular oxygen or a molecular oxygen-containing gas, this invention provides a process characterized in that the initial stage operation is carried out under advancedly elevated reaction temperature and thereafter the reaction temperature is lowered to carry out the steady state operation. According to this process, acrolein and/or acrylic acid can be produced in high yield stably over prolonged period.

Process for producing acrolein and/or acrylic acid

The invention offers an improvement in a process for start-up in the occasion of producing acrolein and acrylic acid by catalytically oxidizing propylene at vapor phase under high load conditions, the start-up meaning the step of increasing the propylene supply rate (loading) from the non-reacting condition to the prescribed reaction conditions. This process is characterized in that the propylene supply rate is increased in the start-up stage of the reaction until the prescribed composition of starting reactant gas and the flow rate of the starting reactant gas are obtained, while adjusting at least one of the reaction temperature, the composition of the starting reactant gas and flow rate of the starting reactant gas, so as to maintain the propylene conversion at not lower than 90 mol %, the maximum peak temperature of the catalyst layer in each reaction zone at no higher than 450&#xb0; C., and the sum of each &#x394;T (maximum peak temperature of a catalyst layer&#x2014;reaction temperature) at the catalyst layer in each of the reaction zones to be no more than 180&#xb0; C., respectively. According to this process, the reaction speedily reaches the steady state (standard operating conditions) and a high acrolein and acrylic acid yield is stably achieved from the start of the reaction.

Process for producing acrolein and acrylic acid

The invention offers an improvement in a process for start-up in the occasion of producing acrylic acid by catalytically oxidizing acrolein at vapor phase under high load conditions, the start-up meaning the step of increasing the acrolein supply rate (loading) from the non-reacting condition to the prescribed reaction conditions. This process is characterized in that the acrolein supply rate is increased in the start-up stage of the reaction until the prescribed composition of starting reactant gas and the flow rate of the starting reactant gas are obtained, while adjusting at least one of the reaction temperature, the composition of the starting reactant gas and the flow rate of the starting reactant gas, so as to maintain the acrolein conversion at not lower than 90 mol %, the maximum peak temperature of the catalyst layer in each reaction zone at no higher than 400&#xb0; C., and the sum of each &#x394;T (maximum peak temperature of a catalyst layer-reaction temperature) at the catalyst layer in each of the reaction zones to be no more than 150&#xb0; C., respectively. According to this process, the reaction speedily reaches the steady state (standard operating conditions) and a high acrylic acid yield is stably achieved from the start of the reaction.

Process for producing acrylic acid

Conventional gas-phase catalytic oxidation reaction apparatus comprising two reactors for production of acrylic acid is subject to problems of high equipment costs for the reactors and piping, necessity for wide installation area and easy accumulation of carbides generated by autoxidation of acrolein. On the other hand, conventional reaction apparatus comprising a single reactor has the drawbacks that the composition of gas in the first stage reaction and in the second stage reaction cannot be optimized independently of each other, and that the allowable concentration of starting propylene is limited because of the risk of explosion. As a reaction apparatus to solve these problems, this invention provides a fixed bed shell-and-tube reaction apparatus comprising a single reactor, characterized in that the inside of the reactor is divided into two reaction zones of the first reaction zone and the second reaction zone, and that a space equipped with a mechanism for introducing a gaseous substance from outside is provided between the two reaction zones.

Reactor for gas phase catalytic oxidation and a process for producing acrylic acid using it

The invention provides a method of gas-phase catalytic oxidation, in particular, a production method of (meth)acrylic acid, which enables stable continuous operation of gas-phase catalytic oxidation over a long term, maintaining high yield and suppressing increase in pressure loss. In the method a fixed bed reactor is used, in which a treating agent for removing organic substance and/or carbides, preferably a treating agent having an adsorption capacity of at least 0.05% by mass, as measured by crotonaldehyde as an indicator of organic substance, is disposed on the upstream side of the gas-phase oxidation catalyst layer in respect of the direction of the gas flow. It is desirable that at least a part of the treating agent is exchanged at a frequency of at least once a year.

Method for gas-phase catalytic oxidation using a fixed bed reactor

The present invention provides: a fixed-bed shell-and-tube reactor, which can stably produce an aimed product for a long period when a solid particulate material such as a catalyst is packed and used for each substance; and its usage. The fixed-bed shell-and-tube reactor comprises a plurality of reaction tubes that are packed with a solid particulate material and arranged in parallel, wherein the solid particulate material is weighed so as to be uniform volume, and is packed in each reaction tube in a packing time of not shorter than 30 seconds per liter.

Fixed-bed shell-and-tube reactor and its usage

A support for a gas-phase oxidation catalyst, the support including a solid acid, of which acid strength (H) meets an inequality: &#x2212;5.6&#x2266;H&#x2266;1.5; a gas-phase oxidation catalyst including the above support and a complex oxide containing molybdenum and vanadium as essential components, the complex oxide being supported on the support; a process for producing acrylic acid by gas-phase catalytic oxidation of acrolein with molecular oxygen, the process including carrying out the gas-phase catalytic oxidation in a presence of the above gas-phase oxidation catalyst; and a process for producing the above support, the process including controlling an acid strength (H) of a solid acid so as to meet an inequality: &#x2212;5.6&#x2266;H&#x2266;1.5 by adjusting a calcination temperature in a preparation of the solid acid contained in the support.

Support for gas-phase oxidation catalyst and process for its production, gas-phase oxidation catalyst, and process for producing acrylic acid

There are disclosed a catalyst and a process for production of acrylic acid using this catalyst, wherein, even under conditions where hot spots are formed, the catalyst is excellent in activity, selectivity, and catalyst life time and displays stable performances for a long time. The catalyst is shown by the following formula (1):MoVWCuABCO&#x2003;&#x2003;(1)(wherein: A is at least one species selected from among cobalt, nickel, iron, lead, and bismuth; B is at least one species selected from among antimony, niobium, and tin; and C is at least one species selected from among silicon, aluminum, titanium, and zirconium; and further, a, b, c, d, e, f, g, and x are atomic ratios of Mo, V, W, Cu, A, B, C, and O respectively; and, in the case of a=, the following inequalities are satisfied: 2&#x2266;b&#x2266;15; 0&#x3c;c&#x2266;10; 0&#x3c;d&#x2266;6; 0&#x3c;e&#x2266;30; 0&#x2266;f&#x2266;6; and 0&#x2266;g&#x2266;60; and x is a numerical value as determined by the oxidation state of each element); wherein a supply source of a component A for preparing the catalyst is a composite of the component A and at least one species selected from among Mo, V, and Cu.

Composite-oxide catalyst and process for production of acrylic acid using said catalyst

A catalyst for production of acrylic acid which catalyst is so high in activity as to give a still higher selectivity of acrylic acid or a long-catalytic-life-time catalyst for production of acrylic acid which catalyst is so high in activity as to be able to give a high acrylic acid yield while suppressing the temperature rise of the oxidation reaction to a low one; and processes for production of acrylic acid using these catalysts. The catalyst includes an oxide and/or a composite oxide as an essential catalytic component, wherein the oxide and/or the composite oxide has a metal element composition shown by general formula (1):MoVWCuO&#x2003;&#x2003;(1)(wherein: when a=12, then 1&#x2266;b&#x2266;14, 0&#x2266;c&#x2266;12, 0 &#x2266;d&#x2266;10, and 0&#x3c;c+d; and x is a numerical value determined by oxidation states of the elements);

Catalyst for production of acrylic acid and process for production of acrylic acid using the catalyst

There are provided a catalyst for catalytic gas phase oxidation of acrolein with molecular oxygen to produce acrylic acid, the catalyst including molybdenum and vanadium and further including at least one volatile catalyst poison ingredient in an amount of 10 to 100 ppb by mass as measured by ion chromatography; and a process for producing acrylic acid, including a step of carrying out catalytic gas phase oxidation of acrolein with molecular oxygen using the catalyst. The catalyst of the present invention can lower a hot spot temperature and suppress reduction in a reaction efficacy accompanied with thermal degradation, so that the acrolein conversion can stably be kept higher over a long term.

Catalyst for catalytic gas phase oxidation of acrolein and process for producing acrylic acid by catalytic gas phase oxidation using said catalyst

An object of the present invention is to provide a catalytic gas phase oxidation reaction in which: even under reaction conditions of a higher gas pressure, a higher concentration of the raw material gas and a larger space velocity of a reaction gas, the thermal accumulation at the hot spot portion can be sufficiently suppressed with ease and at low costs, so that the reaction can be continued for a long time while a high yield is maintained. As a means of achieving this object, a catalytic gas phase oxidation reaction according to the present invention is a catalytic gas phase oxidation reaction with molecular oxygen or a molecular-oxygen-containing gas by using a fixed-bed multitubular reactor packed with catalysts; with the catalytic gas phase oxidation reaction being characterized in that: a catalyst-packed layer of each reaction tube of the reactor is divided into at least two reaction zones in a tubular axial direction; and the packing of the catalysts is such that the occupation volumes of the catalysts differ between at least two of the reaction zones and that an inert substance molding is mixed in at least one of the reaction zones.

Catalytic gas phase oxidation reaction

The object of the present invention is to provide a process in which, when the unsaturated carboxylic acid is produced, or when the unsaturated aldehyde and/or the unsaturated carboxylic acid are produced by carrying out the catalytic gas phase oxidation reaction by using the fixed-bed multitubular reactor which is packed with the molybdenum-containing catalyst, the reaction can be continued for a long time while a high yield is maintained, regardless of where the hot spot portion occurs and also even if the concentration of the raw gas is high. To solve this object, the present invention production process for an unsaturated carboxylic acid is characterized in: a particulate catalysts including, as catalytic components, an oxide and/or a complex oxide including Mo and V, or Mo, Fe and Bi as essential components, and having a hole are used; and a catalyst-packed layer of each reaction tube of the fixed-bed multitubular reactor is divided into at least two reaction zones in a tubular axial direction, wherein the packing of the catalysts is such that the diameters of the holes of the catalysts differ between at least two of the reaction zones.

Growing community of inventors

Himeji, Japan

Michio Tanimoto