Method for recycling denitration catalyst

Patent metadata

Field	Value
Publication number	US-10767535-B2
Application number	US-201715764200-A
Country	US
Kind code	B2
Filing date	Mar 7, 2017
Priority date	Sep 12, 2016
Publication date	Sep 8, 2020
Grant date	Sep 8, 2020

Abstract

There is provided a method for recycling a catalyst that exhibits a high denitration efficiency at a relatively low temperature and does not cause oxidation of SO2 in a selective catalytic reduction reaction that uses ammonia as a reducing agent. A method for recycling a denitration catalyst includes a step of spraying an aqueous solution with a pH of 7 or more onto a used denitration catalyst while the denitration catalyst is set in a denitration device to remove a surface of the denitration catalyst. The denitration catalyst contains 43 wt % or more of vanadium pentoxide and has a BET specific surface area of 30 m2/g or more. The denitration catalyst after recycling is used for denitration at 200° C. or lower.

First claim

The invention claimed is:

1. A method for recycling a denitration catalyst, comprising:
a step of spraying an aqueous solution with a pH of 7 or more onto a used denitration catalyst while the denitration catalyst is set in a denitration device to remove a surface of the denitration catalyst,
wherein the denitration catalyst contains 43 wt % or more of vanadium pentoxide and has a BET specific surface area of 30 m 2 /g or more, and the denitration catalyst after recycling is used for denitration at 200° C. or lower.

2. The method for recycling a denitration catalyst according to claim 1 , wherein the aqueous solution with a pH of 7 or more is an aqueous solution of at least one compound selected from the group consisting of ammonia, an alkali metal hydroxide, Mg(OH) 2 , and an alkaline-earth metal hydroxide.

3. The method for recycling a denitration catalyst according to claim 1 , wherein in the denitration catalyst, an amount of NH 3 desorbed by NH 3 -TPD (TPD: temperature programed desorption) is 10.0 μmol/g or more.

Assignees

• Chugoku Electric Power
• Univ Tokyo Metropolitan

Inventors

• Kiyonaga Eiji
• Hikino Kenji
• Morita Keiichiro
• Yoshikawa Toshikazu
• Haruta Masatake
• Murayama Toru
• Mino Makoto

Classifications

• B01J2235/15

  X-ray diffraction · CPC title

• B01J37/088

  Decomposition of a metal salt · CPC title

• F01N2610/02

  the substance being ammonia or urea · CPC title

• F01N2590/02

  for marine vessels or naval applications · CPC title

• B01J37/0219

  the coating containing organic compounds · CPC title