摘要:
PROBLEM TO BE SOLVED: To provide an exhaust gas treatment catalyst which can be regenerated while suppressing the reduction of catalyst strength and a method of regenerating the exhaust gas treatment catalyst.SOLUTION: An exhaust gas treatment catalyst 10 of the invention denitrifies exhaust gas which is discharged from a heavy oil-fired boiler and contains SOx and V, is made up of titanium (Ti) and silicon (Si), and has carriers 12 whose Si content is 10 wt.% or more and 20 wt.% or less and active components 11 which are deposited on the carriers 12 and contain one kind selected from a group consisting of V and W.
摘要:
A method for activating a catalyst for chlorine production used in a reaction for oxidizing hydrogen chloride with oxygen, including the step of bringing a catalyst for chlorine production having decreased activity into contact with a basic liquid, and a method for producing chlorine by oxidizing hydrogen chloride with oxygen in the presence of a catalyst for chlorine production activated by the above method are provided. The basic liquid used preferably has a pH of 8 or more, and is preferably an aqueous solution in which an inorganic base is dissolved. The catalyst for chlorine production is preferably a catalyst containing ruthenium oxide.
摘要:
PROBLEM TO BE SOLVED: To provide a method of suppressing an increase in SOoxidation rate of a denitration catalyst by removing an inhibiting factor such as silica stuck on the denitration catalyst.SOLUTION: When a silica (Si) component as an inhibitor that causes the SOoxidation rate to increase accumulates on the catalyst surface in the denitration catalyst used for removing nitrogen oxide in a flue gas, the silica component accumulating on the catalyst surface is dissolved, thereby regenerating the catalyst. Accordingly, the inhibitor such as the silica component covering the surface of the denitration catalyst can be removed, thereby enabling to provide the catalyst free from the increase of the SOoxidation rate of the regenerated denitration catalyst.
摘要:
PROBLEM TO BE SOLVED: To provide a method for regenerating an exhaust gas purifying catalyst by which the catalyst to which silicon or phosphorus is adhered is regenerated to have sufficiently-recovered catalytic activity while preventing a catalytic component from being dropped out.SOLUTION: The method for regenerating the exhaust gas purifying catalyst comprises the steps of: firing the used catalyst to which silicon or the like adhered, at 400-700°C; and impregnating the fired catalyst with 1-25 wt.% of an alkali solution, the alkali impregnation step being carried out at a pH of ≥13. According to this regeneration method, organic silicon or the like adhering to the used exhaust gas purifying catalyst is removed and thereby catalytic activity is sufficiently recovered.
摘要:
PROBLEM TO BE SOLVED: To provide a method for concentrating a platinum group element, rhenium and arsenic in a substance to be treated which contains the platinum group element, rhenium and arsenic respectively, and separating each element from the others. SOLUTION: This separating method includes: leaching the substance to be treated such as dust, which has been collected from an exhaust gas produced when various catalysts or the like, for instance, have been melted and smelted in an electric furnace and an oxidation furnace, and contains the platinum group element, rhenium and arsenic, with an alkaline solution such as an NaOH solution; subsequently separating a solid in which the platinum group element is concentrated, from a solution in which the rhenium and arsenic are leached; then adding a chloride such as potassium chloride into the solution; and subsequently separating the solid in which the rhenium is concentrated, from a solution in which the arsenic is concentrated. A liquid temperature in the step of adding the chloride and the subsequent step of solid-liquid separation is preferably 20-40°C. COPYRIGHT: (C)2010,JPO&INPIT
摘要:
PROBLEM TO BE SOLVED: To provide a method for regenerating a catalytic activity of an ion exchange resin used as a catalyst in preparing a fatty acid ester. SOLUTION: The method comprises steps of washing an ion exchange resin having a decreased catalyst activity with a weak acid solution and subsequently substituting its functional group. Thereby the catalytic activity of the ion exchange resin can be regenerated to its initial state. COPYRIGHT: (C)2007,JPO&INPIT