A method for controlling regeneration a catalyst by an exhaust gas purification device includes: measuring a temperature of exhaust gas flowing into a first catalyst unit; estimating a NO.sub.x amount loaded into the first catalyst unit and a slip amount of NO.sub.x of the first catalyst unit by using the temperature and an amount of the exhaust gas of the first catalyst unit; calculating a temperature of a second catalyst unit by using the temperature of the first catalyst unit; and estimating a NO.sub.x amount flowing into the second catalyst unit by using at least one of the slip amount of NO.sub.x of the first catalyst unit and the temperature of the second catalyst unit.

A composite comprises a carbonaceous and a metallic nanotube conjugated with a carbonaceous support. The composite may be used to remove contaminants from water.

A composite comprises a carbonaceous and a metallic nanotube conjugated with a carbonaceous support. The composite may be used to remove contaminants from water.

A composite comprises a carbonaceous and a metallic nanotube conjugated with a carbonaceous support. The composite may be used to remove contaminants from water.

The present invention provides a method for allowing a used inert material that has been subjected to a reaction once, which is disposed of in the background art, to be used again as well as a brand-new one. A method of recovering an inert material of the present invention is characterized by in the fixed-bed reactor, the inert material is loaded in an inert material layer provided between a first-stage catalyst layer and a second-stage catalyst layer, the first-stage catalyst layer is loaded with a first-stage catalyst for producing acrolein from propylene, and the second-stage catalyst layer is loaded with a second-stage catalyst for producing acrylic acid from acrolein, the method comprising the steps of: extracting the inert material from the fixed-bed reactor; washing the extracted inert material; and screening the washed inert material.

A method for recovering a catalyst, wherein a solution containing a reaction mixture obtained by performing a hydrogenation reaction in a presence of a catalyst containing a platinum group metal is brought into contact with a fiber membrane having a group containing an amino group or a thiol group on a surface, thereby recovering the platinum group metal included in the solution is provided.

A method for separation of at least one catalyst or adsorbent from a homogeneous mixture of catalysts or adsorbents, used in a method for treatment of gas or hydrocarbon feedstock, in which the grains of catalysts or adsorbents are separated according to a sorting threshold corresponding to a content of the constituent element that is sought and defined by the user.

The present invention provides a process for producing hydrogen iodide. The process includes providing a vapor-phase reactant stream comprising hydrogen and iodine and reacting the reactant stream in the presence of a catalyst to produce a product stream comprising hydrogen iodide. The catalyst includes at least one selected from the group of nickel, cobalt, cobalt halides, iron, nickel oxide, nickel halides, copper, copper oxide, copper halides, cobalt oxide, ferrous chloride, ferric chloride, iron oxide, zinc, zinc oxide, zinc halides, molybdenum, tungsten, magnesium, magnesium oxide, and magnesium halides. The catalyst is supported on a support.

The present invention provides a process for producing hydrogen iodide. The process includes providing a vapor-phase reactant stream comprising hydrogen and iodine and reacting the reactant stream in the presence of a catalyst to produce a product stream comprising hydrogen iodide. The catalyst includes at least one selected from the group of nickel, cobalt, cobalt halides, iron, nickel oxide, nickel halides, copper, copper oxide, copper halides, cobalt oxide, ferrous chloride, ferric chloride, iron oxide, zinc, zinc oxide, zinc halides, molybdenum, tungsten, magnesium, magnesium oxide, and magnesium halides. The catalyst is supported on a support.

A novel method for catalytic dehydration of glycerol to acrolein is provided. A fixed bed reactor is used, which is placed in a microwave unit. The feedstock is introduced into the fixed bed reactor after being preheated and gasified. Continuous glycerol dehydration occurs in the presence of a microwave-absorbing catalyst in the fixed bed reactor to form acrolein. The microwave-absorbing catalyst is composed of an active component loaded on a core-shell structure which consists of microwave absorbent coated by an oxide. The uniformity of microwave heating can reduce the formation of hot spot during the reaction and hence improve the catalyst stability. The process and operation is simple, and the unit can steadily run for a long time.