Return to search

The Influence on De-NOx of Metal-Oxidation Catalysts with acidic modification

Abstract
The objective of this study is to compare the performance over copper oxide catalyst under nonselective catalytic reduction of nitric oxide with methane and selective catalytic reduction of nitric oxide with propane. The copper catalysts was prepared by impregnating the support Al2O3 with copper nitrate. In order to find the favorable kind and concentration of acid solution¡Awe conducted the modification of three acid solutions on the support Al2O3 in the same normal concentration in the first¡Aand followed by the test of various concentration of the most-favoured acid. The experiment operated condition was as follow¡G
reaction temperature 623K-1023K¡AF/W¡×108000ml/hr.g¡Aoxygen concentration 2¢M¡ANOx inlet concentration 1000ppm.
In view of the result of NSCR reactions with methane over Cu/£^-Al2O3 catalyst¡Athe conversion of De-NOx increased with the increasing loading of copper on Cu/£^-Al2O3¡Aand achieved a max. value when copper loading was 8¢Mwt.. The performance of De-NOx over the modified copper catalysts three different acid with the same normal concentraion¡Ashowed that the best reduction efficiency was with nitric acid modified¡Athen with¡Aand followed with acetic acid¡Aphosphoric acids. Through compared the conversion of De-NOx between non-modified Cu/£^-Al2O3 with modified Cu/£^-Al2O3¡Athere had the best efficiency in treating for NO conversion. It showed that the best efficiency in raising the conversion of NO over copper catalyst is modified with nitric acid¡Athere is not helpful on reduction efficiency of NO by modification with acetic and phosphatic acids. Nevertheless¡Athe higher concentration¡]N¡^ of nitric acid is¡Athe higher efficiency of De-NO is¡F
For the SCR reactions with propane, when the inlet concentraion NO/C3H8 was 1¡Athere has better reductive activity. The trends for the NO conversion versus reaction temperature were similar for the same catalysts used. In general, the NO conversion was an increasing function of copper loading for these copper catalysts. The 8¢Mwt. Cu/£^-Al2O3 was found to enhance the NO conversion. The activity of acid-treated catalysts in nitric acid with 2¢MO2 present had the best NO conversion, while the same order was in NSCR reaction. Treating the supports with a higher concentration of acid would result in a higher activity for the copper catalyst, implying that acid treatment not only duces surface area to decrease on catalyst and enhance the reactivity, but also the presence of Cu+ and Cu2+ might be responsible for the reaction efficiency. no matter what the reactant is propane or methan , propane is better reactant to catalyst NO to N2.

Identiferoai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0912101-165124
Date12 September 2001
CreatorsHuang, Ling-Hsuan
ContributorsChung-Hsuan Hung, Jie-Chung Lou, Jui-Jen Chen, Hsisheng Teng
PublisherNSYSU
Source SetsNSYSU Electronic Thesis and Dissertation Archive
LanguageCholon
Detected LanguageEnglish
Typetext
Formatapplication/pdf
Sourcehttp://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0912101-165124
Rightsoff_campus_withheld, Copyright information available at source archive

Page generated in 0.0021 seconds