Influence of alkali earth metals on Ce/TiO2 catalyst for selective catalytic reduction of NO with NH3

The salts of alkali earth metals (Ca and Mg) in fly ash have a deactivation effect on SCR catalyst. In this study, the poisoning effect of Ca and Mg on Mn/TiO2 catalyst was investigated and explained based on experimental and characterization results of BET, XRD, H2-TPR, NH3-TPD and XPS. It was found that the deactivation effect of Ca is more obvious than that of Mg. The results showed that the drop of redox ability and Brønsted acidity, and the decrease of active oxygen species led to the decrease of Ca-Ce/TiO2 and Mg-Ce/TiO2.

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Poisoning Effects of Phosphorus, Potassium and Lead on V2O5-WO3/TiO2 Catalysts for Selective Catalytic Reduction with NH3

Catalysts ◽

10.3390/catal10030345 ◽

2020 ◽

Vol 10 (3) ◽

pp. 345

Author(s):

Jifa Miao ◽

Xianfang Yi ◽

Qingfa Su ◽

Huirong Li ◽

Jinsheng Chen ◽

...

Keyword(s):

Catalytic Reduction ◽

Active Oxygen Species ◽

Negative Influence ◽

Acid Sites ◽

Active Oxygen ◽

Oxygen Species ◽

Poisoning Effect ◽

The Past ◽

Nox Conversion ◽

Vanadium Species

The poisoning effect of single elements on commercial V2O5-WO3/TiO2 catalysts has been studied in the past decades. In this study, the combined effects of two multi-element systems (phosphorus-potassium and phosphorus-lead) on V2O5-WO3/TiO2 catalysts were studied by diverse characterizations. The results show that potassium and lead can result in the deactivation of catalysts to different degrees by reacting with active acid sites and reducing the amount of V5+. However, phosphorus displays slight negative influence on the NOx conversion of the catalyst due to the comprehensive effect of reducing V5+ amount and generating new acid sites. The samples poisoned by phosphorus–potassium and phosphorus–lead have higher NOx conversion than that by potassium or lead, because doped potassium or lead atoms may react with new acid sites generated by phosphate, which liberates more V–OH on the surface of catalysts and reduces the poisoning effects of potassium or lead on vanadium species and active oxygen species.

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The synergistic effect in Co–Ce oxides for catalytic oxidation of diesel soot

Catalysis Science & Technology ◽

10.1039/c4cy01141d ◽

2015 ◽

Vol 5 (2) ◽

pp. 1084-1092 ◽

Cited By ~ 64

Author(s):

Guchu Zou ◽

Yao Xu ◽

Shujie Wang ◽

Mingxia Chen ◽

Wenfeng Shangguan

Keyword(s):

Synergistic Effect ◽

Catalytic Oxidation ◽

Oxygen Vacancies ◽

Active Oxygen Species ◽

Diesel Soot ◽

Active Oxygen ◽

Oxygen Species ◽

Soot Combustion ◽

Redox Ability

Oact: active oxygen species. C*[O]: carbon–oxygen intermediate. The synergistic effect in Co–Ce catalyst leads to more oxygen vacancies and enhanced redox ability, thus assisting soot combustion.

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Characterization and functional properties of new everbearing strawberry (Fragaria x ananasa Duch.) cultivar, ‘Summertiara’ berries

Functional Foods in Health and Disease ◽

10.31989/ffhd.v4i1.27 ◽

2014 ◽

Vol 4 (1) ◽

pp. 1 ◽

Cited By ~ 1

Author(s):

Takeshi Nagai ◽

Misuzu Tamai ◽

Masato Sato ◽

Yasuhiro Tanoue ◽

Norihisa Kai ◽

...

Keyword(s):

Vitamin C ◽

Sensory Evaluation ◽

Functional Properties ◽

Active Oxygen Species ◽

Active Oxygen ◽

Antihypertensive Activity ◽

Oxygen Species ◽

Total Anthocyanins ◽

Strawberry Cultivar ◽

The Stability

Background: In recent years, a new everbearing strawberry cultivar, ‘Summertiara’ was cultivated to supply the strawberries in pre-harvest season from July to October in Japan. For highly research and development of processing of this cultivar, ‘Summertiara’ berries, the objective of this study was to characterize these berries, with relation to chemical parameters, total phenols, total flavonoids, total vitamin C, and total anthocyanins, and was to investigate the solubility and the stability of anthocyanins from the berries. Moreover, the functional properties such as antioxidative activity, active oxygen species scavenging activity, and antihypertensive activity were also evaluated.Methods: Chemical analysis, colour measurement, and sensory evaluation of new everbearing strawberry cultivar, ‘Summertiara’ berries were performed. Next, the solubility of anthocyanins from the berries and stability of these against pH, temperature, and an incandescent lighting were investigated. Moreover, functional properties of the extracts prepared from berries were elucidated using 5 different methods.Results: The contents of water, proteins, lipids, carbohydrates, and ash were the same as those of other cultivar berries. The sugar-acid ratio in the berries was low; these were acidulous. By sensory evaluation, the main factors were vivid red colour, aroma, and acidity. The berries were rich in phenols, flavonoids, vitamin C, and anthocyanins. The anthocyanins of the berries became unstable by heat treatment and light exposures such as visible rays. On the other hand, the extracts prepared from the berries showed the functionalities such as antioxidant activity, active oxygen species scavenging activities, and antihypertensive activity. Conclusions: The strawberry cultivar, ‘Summertiara’ berries were the most suitable for processing ingredient of strawberry-derived products with superior health promoting functionalities.Keywords: Summertiara, everbearing strawberry cultivar, characterization, sensory evaluation, color and storage, functional property

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