The chemical reactions of nitric oxide with solid carbon and catalytically with gaseous carbon monoxide

Fuel ◽  
2015 ◽  
Vol 142 ◽  
pp. 260-267 ◽  
Author(s):  
Deborah Allen ◽  
Allan N. Hayhurst
Keyword(s):  
Nitric Oxide ◽  
Carbon Monoxide ◽  
Chemical Reactions ◽  
Solid Carbon ◽  
Gaseous Carbon Monoxide

New phases and chemical reactions in solid carbon monoxide under pressure

1984 ◽  
Vol 88 (15) ◽  
pp. 3176-3179 ◽  
Author(s):  
Allen I. Katz ◽  
David Schiferl ◽  
Robert L. Mills
Keyword(s):  
Carbon Monoxide ◽  
Chemical Reactions ◽  
Solid Carbon

Comparison of Iron and Chromium Reduction from Chrome Ore Concentrates by Solid Carbon and Carbon Monoxide

2020 ◽  
Vol 299 ◽  
pp. 1152-1157
Author(s):  
N.Zh. Mukashev ◽  
N.Y. Kosdauletov ◽  
B.T. Suleimen
Keyword(s):  
Carbon Monoxide ◽  
Chromium Content ◽  
Reduction Process ◽  
Complex Oxides ◽  
Solid Carbon ◽  
Continuous Layer ◽  
Chromium Ore ◽  
Gas Atmosphere ◽  
Further Development ◽  
Gaseous Carbon Monoxide

The possibility of reduction of chromium and iron from complex oxides by gaseous carbon monoxide and solid carbon was investigated. The chromium ore concentrates of Kempirsai and Aganozero deposits used in present study had different ratio of iron and chromium content. The Reduction in CO gas atmosphere did not result in reduction of chromium and iron from spinels; however, it resulted in reduction of fines from the drying apparatus, where the particles of coke presented along with the particles of the Kempersai chromite. At the same time, iron and nickel were reduced from the silicates of the gangue minerals. In the samples mixed with solid carbon a continuous layer of carbides formed on the surface of the spinel grains. The formation of a continuous shell retarded and practically stopped the reduction process. The further development of reduction was possible after destruction of the shell that occurred as a result of smelting of the carbides and silicides mixture that constitute the shell.

Ultra-Low Amounts of Palladium (0.005-0.05 Wt% Pd) Supported on Titania: Remarkable Low-Temperature Activity for NO Reduction with CO and Structure-Function Property Relationships in Methane Oxidation

2020 ◽  
Author(s):  
Konstantin Khivantsev ◽  
Libor Kovarik ◽  
Nicholas R. Jaegers ◽  
János Szanyi ◽  
Yong Wang
Keyword(s):  
Nitric Oxide ◽  
Carbon Monoxide ◽  
Methane Oxidation ◽  
Steam Reforming ◽  
Methane Steam Reforming ◽  
Oxide Reduction ◽  
Water Steam ◽  
Methane Steam ◽  
Anatase Titania ◽  
Nitric Oxide Reduction

<p>Atomically dispersed Pd +2 cations with ultra-dilute loading of palladium (0.005-0.05 wt%) were anchored on anatase titania and characterized with FTIR, microscopy and catalytic tests. CO infrared adsorption produces a sharp, narrow mono-carbonyl Pd(II)-CO band at ~2,130 cm<sup>-1</sup> indicating formation of highly uniform and stable Pd+2 ions on anatase titania. The 0.05 wt% Pd/TiO<sub>2</sub> sample was evaluated for methane combustion under dry and wet (industrially relevant) conditions in the presence and absence of carbon monoxide. Notably, we find the isolated palladium atoms respond dynamically upon oxygen concentration modulation (switching-on and switching off). When oxygen is removed from the wet methane stream, palladium ions are reduced to metallic state by methane and catalyze methane steam reforming instead of complete methane oxidation. Re-admission of oxygen restores Pd<sup>+2</sup> cations and switches off methane steam reforming activity. Moreover, 0.05 wt% Pd/TiO<sub>2</sub> is a competent CO oxidation catalyst in the presence of water steam with 90% CO conversion and TOF ~ 4,000 hr<sup>-1</sup> at 260 ⁰C. </p><p>More importantly, we find that diluting 0.05 wt% Pd/titania sample with titania to ultra-low 0.005 wt% palladium loading produces a remarkably active material for nitric oxide reduction with carbon monoxide under industrially relevant conditions with >90% conversion of nitric oxide at 180 ⁰C (~460 ppm NO and 150 L/g*hr flow rate in the presence of >2% water steam) and TOF ~6,000 hr<sup>-1</sup>. Pd thus outperforms state-of-the-art rhodium containing catalysts with (15-20 times higher rhodium loading; rhodium is ~ 3 times more expensive than palladium). Furthermore, palladium catalysts are more selective towards nitrogen and produce significantly less ammonia relative to the more traditional rhodium catalysts due to lower Pd amount nd lower water-gas-shift activity. Our study is the first example of utilizing ultra-low (0.05 wt% and less) noble metal (Pd) amounts to produce heterogeneous catalysts with extraordinary activity for nitric oxide reduction. This opens up a pathway to study other Pd, Pt and Rh containing materials with ultra-low loadings of expensive noble metals dispersed on titania or titania-coated oxides for industrially relevant nitric oxide abatement.</p>

scholarly journals Cloned, expressed rat cerebellar nitric oxide synthase contains stoichiometric amounts of heme, which binds carbon monoxide.

1992 ◽  
Vol 89 (23) ◽  
pp. 11141-11145 ◽  
Author(s):  
K. McMillan ◽  
D. S. Bredt ◽  
D. J. Hirsch ◽  
S. H. Snyder ◽  
J. E. Clark ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Carbon Monoxide ◽  
Nitric Oxide Synthase ◽  
Oxide Synthase

scholarly journals Nitric oxide inhibits, and carbon monoxide activates, islet acid α-glucoside hydrolase activities in parallel with glucose-stimulated insulin secretion

2006 ◽  
Vol 190 (3) ◽  
pp. 681-693 ◽  
Author(s):  
Henrik Mosén ◽  
Albert Salehi ◽  
Ragnar Henningsson ◽  
Ingmar Lundquist
Keyword(s):  
Nitric Oxide ◽  
Carbon Monoxide ◽  
Insulin Secretion ◽  
Insulin Release ◽  
Islets Of Langerhans ◽  
Direct Effect ◽  
Appreciable Effect ◽  
Intact Mouse ◽  
Glucose Stimulated Insulin Secretion ◽  
Glucoside Hydrolases

We have studied the influence of nitric oxide (NO) and carbon monoxide (CO), putative messenger molecules in the brain as well as in the islets of Langerhans, on glucose-stimulated insulin secretion and on the activities of the acid α-glucoside hydrolases, enzymes which we previously have shown to be implicated in the insulin release process. We have shown here that exogenous NO gas inhibits, while CO gas amplifies glucose-stimulated insulin secretion in intact mouse islets concomitant with a marked inhibition (NO) and a marked activation (CO) of the activities of the lysosomal/vacuolar enzymes acid glucan-1,4-α-glucosidase and acid α-glucosidase (acid α-glucoside hydrolases). Furthermore, CO dose-dependently potentiated glucose-stimulated insulin secretion in the range 0.1–1000 μM. In intact islets, the heme oxygenase substrate hemin markedly amplified glucose-stimulated insulin release, an effect which was accompanied by an increased activity of the acid α-glucoside hydrolases. These effects were partially suppressed by the guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one. Hemin also inhibited inducible NO synthase (iNOS)-derived NO production probably through a direct effect of CO on the NOS enzyme. Further, exogenous CO raised the content of both cGMP and cAMP in parallel with a marked amplification of glucose-stimulated insulin release, while exogenous NO suppressed insulin release and cAMP, leaving cGMP unaffected. Emiglitate, a selective inhibitor of α-glucoside hydrolase activities, was able to markedly inhibit the stimulatory effect of exogenous CO on both glucose-stimulated insulin secretion and the activityof acid glucan-1,4-α-glucosidase and acid α-glucosidase, while no appreciable effect on the activities of other lysosomal enzyme activities measured was found. We propose that CO and NO, both produced in significant quantities in the islets of Langerhans, have interacting regulatory roles on glucose-stimulated insulin secretion. This regulation is, at least in part, transduced through the activity of cGMP and the lysosomal/vacuolar system and the associated acid α-glucoside hydrolases, but probably also through a direct effect on the cAMP system.

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