Regenerated denitration catalyst and method for manufacturing the same, and denitration apparatus

Patent metadata

Field	Value
Publication number	US-12427509-B2
Application number	US-202017296811-A
Country	US
Kind code	B2
Filing date	Dec 2, 2020
Priority date	Jan 31, 2020
Publication date	Sep 30, 2025
Grant date	Sep 30, 2025

Abstract

It is an object to provide a regenerated denitration catalyst whose denitration performance is restored compared with a denitration catalyst before use, utilizing a spent denitration catalyst, and a method for manufacturing the same. In a regenerated denitration catalyst according to the present disclosure, a spent denitration catalyst including a first titanium oxide as a main component, and a second titanium oxide are mixed. The spent denitration catalyst is already used in a denitration reaction in which nitrogen oxides in a gas are decomposed into nitrogen and water using a reducing agent. The second titanium oxide has a larger specific surface area per unit weight than the first titanium oxide. A content of the second titanium oxide based on a total weight of the first titanium oxide and the second titanium oxide is preferably 10% by weight or more and 90% by weight or less.

First claim

The invention claimed is:

1. A method for manufacturing a regenerated denitration catalyst for a denitration reaction, the method comprising:
using a mixed powder obtained by mixing a spent denitration catalyst powder comprising a first titanium oxide as a main component, and a second titanium oxide, and vanadium or a vanadium compound,
the spent denitration catalyst powder being obtained by grinding a spent denitration catalyst of honeycomb structure,
the spent denitration catalyst already being used in a denitration reaction in which nitrogen oxides in a gas are decomposed into nitrogen and water using a reducing agent, and
the second titanium oxide having a larger specific surface area per unit weight than the first titanium oxide,
the method further comprising:
applying a kneaded mixture of the mixed powder and a solvent on a plate-like substrate and manufacturing a plate-like regenerated denitration catalyst not having honeycomb structure,
wherein a content of vanadium or the vanadium compound is more than 0% by weight and 4% by weight or less based on a total weight of the regenerated denitration catalyst.

2. The method for manufacturing a regenerated denitration catalyst for a denitration reaction according to claim 1 , wherein 10% by weight or more and 90% by weight or less of the second titanium oxide is mixed based on a total weight of the first titanium oxide and the second titanium oxide.

3. The method for manufacturing a regenerated denitration catalyst for a denitration reaction according to claim 1 , wherein a predetermined amount of phosphorus or a phosphorus containing compound is added to the mixed powder.

4. The method for manufacturing a regenerated denitration catalyst for a denitration reaction according to claim 1 , the method comprising a step of coating a surface of the kneaded material applied on the plate-like substrate with vanadium and at least one of molybdenum or tungsten.

5. The method for manufacturing a regenerated denitration catalyst for a denitration reaction according to claim 1 , wherein a total weight of the first titanium oxide and the second titanium oxide based on a total weight of the regenerated denitration catalyst is in a range of 60% by weight to 85% by weight.

Assignees

• Mitsubishi Power Ltd
• Mitsubishi Heavy Ind Ltd

Inventors

• Shishido Satoru
• Urabe Yu
• Kurai Takuma
• Kako Hiroshi
• Nochi Katsumi

Classifications

• B01J35/56

  Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional [3D] monoliths · CPC title

• C01B21/02

  Preparation of nitrogen (by decomposition of ammonia C01B3/047) · CPC title

• C01B5/00

  Water · CPC title

• B01J37/04

  Mixing {(B01J37/0009, B01J37/0018 take precedence)} · CPC title

• B01J37/0217

  Pretreatment of the substrate before coating · CPC title