scholarly journals Hydrocarbons from Carbide (A) III. Non-catalytic Polymerization under Ordinary Pressure. Carbon Dioxide-, Carbon Monoxide-, and Hydrogen Chloride-Calcium Carbide Systems

1942 ◽  
Vol 17 (5) ◽  
pp. 244-251 ◽  
Author(s):  
Ryoji Negishi ◽  
Osamu Kamiike
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Hydrogen Chloride ◽  
Calcium Carbide ◽  
Catalytic Polymerization

Decomposition of PCB's in the radio-frequency glow discharge plasmas of oxygen, hydrogen, and water vapor

1982 ◽  
Vol 60 (22) ◽  
pp. 2876-2882 ◽  
Author(s):  
K. Hiraoka ◽  
K. Aoyama ◽  
T. Nakamura ◽  
S. Mochizuki ◽  
K. Mitsumori ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Water Vapor ◽  
Glow Discharge ◽  
Radio Frequency ◽  
Hydrogen Chloride ◽  
Hydrogen Plasma ◽  
Glow Discharge Plasma ◽  
Radio Frequency Glow Discharge ◽  
Gaseous Products

A study was made on the decomposition of PCB's in a radio-frequency glow discharge plasma. PCB's were completely decomposed in plasmas of a few Torr of oxygen, hydrogen, and water vapor. Gaseous products from PCB's in an oxygen plasma were carbon monoxide, carbon dioxide, water, hydrogen chloride, chlorine, and chlorine dioxide. Hazardous compounds such as phosgene and vinyl chloride were not detected by gc–ms analysis. The total quantity of oxygen flowed past the sample was only about three times the stoichiometric oxygen required for the perfect oxidation of PCB's. In a hydrogen plasma, PCB's gave ethane and isobutane as major gaseous products and several higher hydrocarbons as minor products. Almost all of the chlorine in PCB's was converted to hydrogen chloride. Major products from PCB's in a water vapor plasma were carbon dioxide, carbon monoxide, and hydrogen chloride. No other products were detected. The mechanisms for reactions occurring in plasmas are discussed. The importance of the wall effect for the formation of solid products is discussed.

scholarly journals Determination of the Critical Time of Fire in the Building and Ensure Successful Evacuation of People

2019 ◽  
Author(s):  
Eduard Hulida ◽  
Ivan Pasnak ◽  
Oleksandr Koval ◽  
Anatolii Tryhuba
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Hydrogen Chloride ◽  
Oxygen Concentration ◽  
Relative Error ◽  
Critical Time ◽  
Engineering Method ◽  
Methods Of Calculation ◽  
Critical Phase

An engineering method was developed for determining the critical time of fire and determining the probability of evacuation of people from zone of fire, which makes it possible, with simplified dependencies, to quickly determine all the necessary factors in the evacuation process of people in case of fire in the building. To explain the use of the developed method, the sequence and example of determining the critical time of fire and determining the probability of evacuation of people from zone of fire for enterprise is considered. It was shown how one could calculate the time of evacuation of people from the premises from the zone of fire. The safety of people is provided when the time of evacuation does not exceed the time of the onset of the critical phase of the development of fire. For this purpose, the period for which the temperature, smoke density, oxygen concentration, hydrogen chloride, carbon dioxide and carbon monoxide gas reaches extremely dangerous values for a person was calculated. After determining all the necessary quantities, the probability of evacuation of people was analyzed in the absence of firefighting equipment in the building. The parameters determined by this new method are adequate and confirmed by other methods of calculation, in particular, developed by Hulida, Koval and FDS program. The relative error between the specified parameters does not exceed 8...12% (in comparison with other mentioned methods).

scholarly journals Controlled atmosphere GMAW welding of transportation vehicles and production machines parts made from 30MnB5 steel

2018 ◽  
Vol 216 ◽  
pp. 03001 ◽  
Author(s):  
Evgeny Ivanayskiy ◽  
Aleksei Ishkov ◽  
Aleksandr Ivanayskiy ◽  
Iakov Ochakovskii
Keyword(s):  
Mechanical Properties ◽  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Chemical Composition ◽  
Controlled Atmosphere ◽  
Shielding Gas ◽  
Reducing Atmosphere ◽  
Metal Composition ◽  
Gmaw Welding ◽  
Welding Materials

The paper studies the influence of shielding gas on the composition and the structure of weld joint metal of 30MnB5 steel applied in essential parts of automobiles and tractors. The welding was performed in inert, oxidizing and reducing atmospheres. It was established that TIG welding with argon used as shielding gas did not provide the required mechanical properties when using conventional welding materials. Carbon dioxide during MAG welding caused partial burning of alloying elements. Carbon monoxide used as shielding gas was proved to form reducing atmosphere enabling to obtain chemical composition close to the base metal composition. Metallographic examinations were carried out. The obtained results provided full-strength weld, as well as the required reliability and durability of welded components and joints.

Low-Carbon Monoxide Hydrogen by Sorption-Enhanced Reaction

2003 ◽  
Vol 1 (1) ◽  
Author(s):  
Douglas P Harrison ◽  
Zhiyong Peng
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Hydrogen Production ◽  
Proton Exchange Membrane ◽  
Primary Energy ◽  
Proton Exchange ◽  
Raw Material ◽  
Impurity Level ◽  
Low Carbon ◽  
Enhanced Production

Hydrogen is an increasingly important chemical raw material and a probable future primary energy carrier. In many current and anticipated applications the carbon monoxide impurity level must be reduced to low-ppmv levels to avoid poisoning catalysts in downstream processes. Methanation is currently used to remove carbon monoxide in petroleum refining operations while preferential oxidation (PROX) is being developed for carbon monoxide control in fuel cells. Both approaches add an additional step to the multi-step hydrogen production process, and both inevitably result in hydrogen loss. The sorption enhanced process for hydrogen production, in which steam-methane reforming, water-gas shift, and carbon dioxide removal reactions occur simultaneously in the presence of a nickel-based reforming catalyst and a calcium-based carbon dioxide sorbent, is capable of producing high purity hydrogen containing minimal carbon monoxide in a single processing step. The process also has the potential for producing pure CO2 that is suitable for subsequent use or sequestration during the sorbent regeneration step. The current research on sorption-enhanced production of low-carbon monoxide hydrogen is an extension of previous research in this laboratory that proved the feasibility of producing 95+% hydrogen (dry basis), but without concern for the carbon monoxide concentration. This paper describes sorption-enhanced reaction conditions – temperature, feed gas composition, and volumetric feed rate – required to produce 95+% hydrogen containing low carbon monoxide concentrations suitable for direct use in, for example, a proton exchange membrane fuel cell.

scholarly journals The flame spectrum of carbon monoxide

1940 ◽  
Vol 176 (967) ◽  
pp. 505-521 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Electronic State ◽  
Excited Electronic State ◽  
Combustion Process ◽  
Wave Number ◽  
Band Spectrum ◽  
Liquid Form ◽  
Triangular Form ◽  
Reduced Pressure

The spectrum of the flame of carbon monoxide burning in air and in oxygen at reduced pressure has been photographed on plates of high contrast which display the band spectrum clearly above the continuous background. Greater detail has been obtained than has been recorded previously and new measurements are given. The structure of the spectrum has been studied systematically. It is shown that the bands occur in pairs with a separation of about 60 cm. -1 , this separation being due probably to the rotational structure. Various wave-number differences are found to occur frequently, and many of the strong bands are arranged in arrays using intervals of 565 and 2065 cm. -1 . The possible origin of the spectrum is discussed. The choice of emitter is limited to a polyatomic oxide of carbon, of which carbon dioxide is the most likely. The spectrum of the suboxide C 3 O 2 shows some resemblance to the flame bands, but this molecule is improbable as the emitter on other grounds. A peroxide C0 3 is also a possibility, but no evidence for the presence of this has been obtained from experiments on the slow combustion of carbon monoxide. Carbon dioxide in gaseous or liquid form is transparent through the visible and quartz ultra-violet, and the flame bands are not obtained from CO 2 in discharge tubes. Comparison with the Schumann-Runge bands of oxygen shows that it is possible that the flame bands may form part of the absorption band system of CO 2 which is known to exist below 1700 A if there is a big change in shape or size of the molecule in the two electronic states. The electronic energy levels of CO 2 are discussed. Since normal CO 2 is not built up from normal CO and oxygen, an electronic rearrangement of the CO 2 must occur after the combustion process. Mulliken has suggested that the molecule in the first excited electronic state, corresponding to absorption below 1700 A, may have a triangular form. The frequencies obtained from the flame bands are compared with the infra-red frequencies of CO 2 . The 565 interval may be identified with the transverse vibration v 2 , indicating that the excited electronic state is probably triangular in shape. The 2065 interval cannot, however, be identified with the asymmetric vibration v 3 with any certainty. If the excited electronic state of CO 2 is triangular, then molecules formed during the combustion by transitions from this level to the ground state may be “vibrationally activated”. This is probably the reason for many of the peculiarities of the combustion of carbon monoxide.

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