Reductive formation of carbon monoxide from carbon tetrachloride and FREONS 11, 12, and 13 catalyzed by corrinoids

Biochemistry ◽  
1991 ◽  
Vol 30 (10) ◽  
pp. 2713-2719 ◽  
Author(s):  
Ute E. Krone ◽  
Rudolf K. Thauer ◽  
Harry P. C. Hogenkamp ◽  
Klaus Steinbach
Keyword(s):  
Carbon Monoxide ◽  
Carbon Tetrachloride

Reductive Activation of Carbon Tetrachloride by Human Haemoglobin

1993 ◽  
Vol 21 (1) ◽  
pp. 57-64
Author(s):  
Roberta Ferrara ◽  
Michela Rezzadore ◽  
Stefano Cazzaro ◽  
Roberto Tolando ◽  
Maurizio Manno
Keyword(s):  
Carbon Monoxide ◽  
Carbon Tetrachloride ◽  
Anaerobic Incubation ◽  
Reductive Activation ◽  
Anaerobic Conditions ◽  
Prosthetic Group ◽  
Experimental Conditions ◽  
Human Haemoglobin ◽  
Reductive Metabolism

The reductive metabolism of carbon tetrachloride (CC14) by human haemoglobin (Hb) was observed in vitro by absolute absorption spectra recorded under anaerobic conditions. The following results were obtained: 1) a decrease of the 430nm peak typical of free reduced Hb (Hb2+); 2) the formation of a shoulder of absorbance, attributable to the production of a complex between Hb2+ and a metabolite of CC14 carbon monoxide (Hb-CO); and 3) the oxidation of some Hb2+ to methaemoglobin (Hb3+). The concentration of these three forms — Hb2+, Hb-CO and Hb3+ — during anaerobic incubation of Hb with CC14 was calculated algebraically from the absolute spectra. CO production was then calculated from the concentration of Hb-CO, using a suitable calibration curve. Interestingly, under identical experimental conditions, a substrate-dependent loss of Hb-derived haem, but not of Hb itself nor of haem-derived porphyrin fluorescence, was measured. Preliminary HPLC studies to clarify the discrepancy and, in particular, the role and fate of the haem group, showed two substrate-dependent modified haem products. The results indicate that human Hb is able to catalyse the reductive activation of CCl4, and suggest that, during the process, its prosthetic group haem may be modified by CC14 metabolites to products which maintain a tetrapyrrolic structure but are unable to react with pyridine.

The hydrolysis of chloroform and carbon tetrachloride by anion-exchange resins

1968 ◽  
Vol 21 (12) ◽  
pp. 2933
Author(s):  
HF Ryan
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Carbon Tetrachloride ◽  
Anion Exchange ◽  
Probable Explanation ◽  
Anion Exchange Resins ◽  
Apparent Loss ◽  
Exchange Resins ◽  
Most Probable Explanation ◽  
Hydrolysis Of

Chloroform in acetone or ethanol solvent was rapidly hydrolysed to carbon monoxide and formate by Amberlite XE-78 in the OH-form. Hydroxyl sites on the resin were converted into chloride. The apparent loss in capacity of the resin which occurs during the reaction cannot be wholly accounted for by production of formate. The most probable explanation for the phenomenon is the adsorption of carbon trichloride anions at resin sites. Carbon tetrachloride in ketonic solvents also gave carbon monoxide and formate in the presence of the OH-form of the resin, but in alcohol or ether solvent carbon dioxide and phosgene were formed.

Spectra produced by shock waves, flames and detonations

1957 ◽  
Vol 239 (1219) ◽  
pp. 464-475 ◽  
Keyword(s):  
Carbon Monoxide ◽  
Carbon Tetrachloride ◽  
Shock Waves ◽  
Strong Shock ◽  
Emission Spectra ◽  
Propagation Mechanism ◽  
Carbon Formation ◽  
Promising Technique ◽  
Discharge Tubes ◽  
Strong Shock Waves

Emission spectra excited in various gases, including fuel and fuel+argon mixtures, by strong shock waves from a bursting diaphragm are compared with those given by flames and by spark-ignited and shock-ignited detonations. Shocks through hydrocarbon or hydrocarbon+argon mixtures, without oxygen, give carbon formation and C 2 emission but not CH. Formaldehyde, ether, alcohols, ethyl nitrate, carbon tetrachloride and chloroform have also been studied. Carbon monoxide+argon mixtures give strong C 2 but no CO bands; hydrogen or oxygen only slightly quench this C2, but mixed hydrogen and oxygen quench it strongly. Reactions involving C 2 and CH are discussed. In detonations, OH is very strong, and C 2 and CH are weak compared with burner flames. Time records, using a photomultiplier and oscillograph, indicate that C 2 emission comes from the reaction zone of the detonation, but OH and the continuous spectrum are emitted mainly by the hot gases behind the front. The relation of the results to the propagation mechanism is briefly discussed. Shock-excited spectra resemble those produced by flames rather than those from discharge tubes, and this appears to be a promising technique for studying fundamental processes in flames.

Carbon tetrachloride-altered binding of carbon monoxide to reduced cytochrome P-450 in phenobarbital microsomes

1980 ◽  
Vol 23 (2) ◽  
pp. 205-208
Author(s):  
Wayne R. Bidlack ◽  
Shakuntala V. Advani ◽  
Jeffrey W. Andresen
Keyword(s):  
Carbon Monoxide ◽  
Carbon Tetrachloride ◽  
Cytochrome P 450

Ilmenite Chlorination: Usage of Gaseous Carbon Tetrachloride at Relatively Lower Temperatures

2015 ◽  
Vol 1087 ◽  
pp. 389-393
Author(s):  
Norazharuddin Shah Abdullah ◽  
Azizan Aziz ◽  
Hussin Kamarudin
Keyword(s):  
Carbon Monoxide ◽  
Carbon Tetrachloride ◽  
Hydrogen Chloride ◽  
Size Fraction ◽  
Kinetic Studies ◽  
Chemical Complexity ◽  
Major Interest ◽  
Chlorine Gas ◽  
Physical And Chemical ◽  
Parameter Values

Malaysian ilmenite from “amang” or tin mining waste is well known for its physical and chemical complexity, making it difficult to be treated conventionally. With knowledge of ilmenite is rich in titania and iron, extractive efforts were made in order to segregate and recover the components of ilmenite, with major interest being the removal and retrieval of titanium. In this study, the extent of chlorination execution is observed by means of weight loss studies under various parameters, with an aim of successful chlorination at lower temperatures. At 723 K, chlorination trials were done using gaseous hydrogen chloride (gHCl), carbon monoxide-chlorine gas mixtures (gCO-Cl) and gaseous carbon tetrachloride (gCT). It was clearly seen that at such a relatively low temperature, only gCT was able to obtain a good chlorination degree, with up to 90% chlorination of –45+37 μm ilmenite particles were observed after 1 hour of reaction. With similar size fraction and time, hydrogen chloride was only able to give approximately 6% of chlorination while the mixture of carbon monoxide and chlorine was seen incapable of giving anything higher than a 6% reaction. Initial observation suggests that the chlorination of ilmenite by carbon tetrachloride physically resembles the core shrinking model, although proper kinetic studies needs to be done to confirm this. Changes in various parameter values are seen to be quite sensitive to the overall ilmenite chlorination (via gCT) process. This study have shown that gCT presents an interesting route for the chlorination of complex ores such as ilmenite.

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