scholarly journals Hydrogenation of Clean Carbon Monoxide (CO) and Carbon Dioxide (CO2) Gas Streams to Higher Molecular Weight Alcohols

2012 ◽  
Author(s):  
Not Given Author
Volume 2 ◽  
2004 ◽  
Author(s):  
Madhuri Jakkaraju ◽  
Vasudha Patri

I. C. Engines consume large amounts of fossil fuel emitting harmful pollutants like carbon monoxide (CO), unburnt hydrocarbons (UBHC), and oxides of nitrogen (NOx). By using a catalytic converter (CC), the carbon monoxide, hydrocarbon emissions can be transformed into less harmful carbon dioxide (CO2) & water vapor (H2O). Currently available CC’s are using costly noble metals like platinum (pt), palladium (pd), rhodium (rh) etc., hence making them expensive. This paper deals with the use of low-cost palletized silver coated alumina as the catalyst element in a CC. In this study, alumina and silver were used in the ratio of 10:1. All tests have been conducted on a stationary S.I. Engine at a constant speed of 1500 r.p.m with and without CC. Also, the performance of the palletized CC in combination with promoters like Bismuth, Cerium and Lanthanum was tested which have shown better results than silver alone as the coating element. It has been experimentally determined that the CO emissions have dropped from 7.25 (% vol) to 3.03(% vol) and the HC values have reduced from 350 ppm to 190 ppm.


2021 ◽  
Vol 1 (1) ◽  
pp. 14-22
Author(s):  
S.A. Plotnikov ◽  
◽  
Sh.V. Buzikov ◽  
I.S. Kozlov ◽  
◽  
...  

The use of rapeseed oil (RO) in tractor engines and other agricultural machinery in its pure form or a mixture of RO with diesel fuel (DF) imposes a number of limitations associated with some dif-ference in physical and chemical properties. Therefore, the most promising is the use of mixed fuel (MF) consisting of DF and RO. The purpose of these studies is to determine the optimal composi-tion of the MF, consisting of DF and RM by optimizing the approximated dependences of the envi-ronmental indicators of a diesel engine. To solve this problem, bench tests of the operation of the D-245.5S diesel engine (4ChN 11.0 / 12.5) were carried out. The following determined environmental performance indicators of a diesel engine are selected: soot (С), nitrogen oxides (NOx), unburned hydrocarbons (CxHy), carbon dioxide (CO2) and carbon monoxide (CO). The studies were carried out on various compositions of MF, consisting of 80% DF and 20% RO, 55% DF and 45% RO, 20% DF and 80% RO by weight, respectively. As a result of the bench tests, two load characteris-tics were obtained, the one at a speed of n = 1400 min-1 corresponding to the value of the maximum torque, and the second at a speed of n = 1800 min-1 corresponding to the value of the rated power, as well as the external speed characteristic of the D-245.5S tractor diesel engine (4ChN 11.0 / 12.5). The analysis of the obtained experimental data revealed the dependence of environmental indicators on the rotational speed of the diesel engine crankshaft, the average effective pressure and the addi-tion of RO in MF by weight. Using the least squares method, the approximated mathematical de-pendences of the ecological indicators of a diesel engine are determined. The analysis of the ob-tained dependencies showed that: the increase in the crankshaft speed n, the proportion of RO in MF and a decrease in the average effective pressure pe, leads to a decrease in soot С to 4.0%, nitro-gen oxides NOx to 100.0 ppm, unburned hydrocarbons CxHy to 1.0 ppm, carbon dioxide, CO2 up to 2%, and an increase in carbon monoxide CO up to 0.16%. As a result of solving the obtained system of equations for the approximated dependences of environmental indicators, the optimal addition of RO to MF of up to 35% by weight was determined.


2020 ◽  
Vol 14 (1) ◽  
pp. 6285-6294
Author(s):  
R. Arias Gilart ◽  
M. R. B. Ungaro ◽  
C. E. A. Rodríguez ◽  
J. F. F. Hernández ◽  
M. C. Sofia ◽  
...  

In this research, different magnetic treatments were applied to diesel fuel using static magnetic fields of 0.36T of magnetic induction. The magnetic conditioners (MCs) were installed in different positions of the fuel lines in the engine and the magnetic treatment of the diesel was also carried out before introducing it into the engine tanks. The study was conducted using a four-stroke, two-cylinder, Lister Petter (LPWS2) engine with a compression ratio of 23.5:1 and a constant engine speed of 1500 rpm. The emissions of carbon monoxide (CO), carbon dioxide (CO2), oxygen (O2), nitrogen oxides and the temperature of the exhaust gases and the mass consumption of fuel were measured. The highest levels of reduction were achieved with the magnetic treatments that locate the MC directly in the engine's pipes. As the number of MC in the engine pipes increases, the emissions of polluting gases decrease. With the treatment that locates one MC in front of each injector, two MC at the entrance of the filter and two MC in the return of fuel were able to increase the O2 emissions by 6.9% and decrease the CO emissions in about 21.3% in the last load of the generator set. With this treatment a decrease in fuel consumption of 4.89% to 80% of engine load was obtained.


Author(s):  
Mikin V. Patel ◽  
Steven Zangan

Angiography relies on the use of contrast medium for visualization of the vessel. Iodinated contrast can be contraindicated in patients with renal impairment or iodinated contrast allergy, so carbon dioxide (CO2) gas can be a useful alternative. A number of technical and postural parameters can optimize CO2 angiography, and vasodilators can be used to improve imaging of peripheral vessels. Although CO2 has distinct advantages, the limitations of CO2 angiography must be well understood. Operators should be aware that CO2 angiography can lead to overestimation of vessel size and can lead to complications such as transient ischemia of tissues, alterations of blood chemistry, neurotoxicity, and “vapor lock.”


Polymers ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1108
Author(s):  
Dominik Dörr ◽  
Tobias Standau ◽  
Svenja Murillo Castellón ◽  
Christian Bonten ◽  
Volker Altstädt

For the preparation of polylactide (PLA)-based foams, it is commonly necessary to increase the melt strength of the polymer. Additives such as chain extenders (CE) or peroxides are often used to build up the molecular weight by branching or even crosslinking during reactive extrusion. Furthermore, a blowing agent with a low molecular weight, such as carbon dioxide (CO2), is introduced in the foaming process, which might affect the reactivity during extrusion. Offline rheological tests can help to measure and better understand the kinetics of the reaction, especially the reaction between the polymer and the chemical modifier. However, rheological measurements are mostly done in an inert nitrogen atmosphere without an equivalent gas loading of the polymer melt, like during the corresponding reactive extrusion process. Therefore, the influence of the blowing agent itself is not considered within these standard rheological measurements. Thus, in this study, a rheometer equipped with a pressure cell is used to conduct rheological measurements of neat and chemical-modified polymers in the presence of CO2 at pressures up to 40 bar. The specific effects of CO2 at elevated pressure on the reactivity between the polymer and the chemical modifiers (an organic peroxide and as second choice, an epoxy-based CE) were investigated and compared. It could be shown in the rheological experiments that the reactivity of the chain extender is reduced in the presence of CO2, while the peroxide is less affected. Finally, it was possible to detect the recrystallization temperature Trc of the unmodified and unbranched sample by the torque maximum in the rheometer, representing the tear off of the stamp from the sample. Trc was about 13 K lower in the CO2-loaded sample. Furthermore, it was possible to detect the influences of branching and gas loading simultaneously. Here the influence of the branching on Trc was much higher in comparison to a gas loading.


2020 ◽  
Vol 12 (14) ◽  
pp. 5873
Author(s):  
Nur Fatma Fadilah Yaacob ◽  
Muhamad Razuhanafi Mat Yazid ◽  
Khairul Nizam Abdul Maulud ◽  
Noor Ezlin Ahmad Basri

This paper presents a review of carbon dioxide (CO2) emissions from transportation in an attempt to establish a quick and suboptimal update of the methods used to calculate and analyze CO2 emissions from transportation. Transportation is the largest contributor to air pollution through the release of high amounts of CO2 gas into the atmosphere. The methods for calculating and analyzing the carbon footprint of transportation; which is of critical importance in the management of greenhouse gases that contribute to global warming; are still being developed. However; there are some differences in the definitions and methods used to calculate the carbon footprint of transportation in previous studies. This review focuses on the similarities of the methods used to measure CO2 emissions as well as the analyses used to evaluate the emissions. This paper will also highlight the advantages and limitations of each research work. By doing this; the present study contributes to the selection of appropriate methods for calculating CO2 emissions from transportation and draws attention to environmental issues. It is hoped that the implementation of the most appropriate framework will help to reduce CO2 emissions from transportation


Animals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 787 ◽  
Author(s):  
Enver Çavuşoğlu ◽  
Jean-Loup Rault ◽  
Richard Gates ◽  
Donald C. Lay

The swine industry is often forced to euthanize pigs in the first few weeks of life due to injuries, hernias, or unthriftiness. The majority of pigs are euthanized using carbon dioxide (CO2) gas asphyxiation but concerns as to the humaneness of CO2 are increasing. This study compared the euthanasia of weaned pigs using N2O (N2O; n = 9) or CO2 (n = 9), at 50% and 25% min−1 exchange rate, respectively. In addition, we administered an analgesic prior to euthanasia with CO2 (CO2B) exposure as a third treatment (n = 9) to elucidate behaviors indicative of pain. Pigs in the CO2 and N2O treatments lost posture at similar times (latency of 145.0 ± 17.3 and 162.6 ± 7.0 s respectively, p > 0.10), while the CO2B treatment pigs lost posture the soonest (101.2 ± 4.7 s, p < 0.01). The pigs in the CO2B treatment made more escape attempts than the CO2 or N2O pigs (16.4 ± 4.2, 4.7 ± 1.6, 0.3 ± 0.2, respectively; p < 0.0004). However, pigs in N2O squealed more often than either the CO2 or CO2B pigs (9.0 ± 1.6, 2.8 ± 1.2, 1.3 ± 0.6, respectively, p < 0.001). Given the similar time to loss of posture and shorter time displaying open mouth breathing, N2O may cause less stress to pigs; however, the greater number of squeals performed by these pigs suggests the opposite. It was not apparent that any behavior measured was indicative of pain. In conclusion, N2O applied at a 50% min−1 flow rate can be an alternative to CO2 for pig euthanasia.


2011 ◽  
Vol 135-136 ◽  
pp. 347-352 ◽  
Author(s):  
Chang Bao Wen ◽  
Yong Feng Ju ◽  
Wan Lin Li ◽  
Wen Zheng Sun ◽  
Xin Xu ◽  
...  

Carbon dioxide (CO2) gas sensor using surface acoustic wave (SAW) device based on Zinc oxide (ZnO) was developed and fabricated in this paper. The center frequency of SAW device is 203.528 MHz. The input and two output interdigital transducers (IDT) apodized by Morlet wavelet function can improve the side lobe rejection compared with uniform IDT. The ZnO film sensitive to CO2 gas was fabricated in measurement acoustic track of SAW device. Experiments results confirm that the CO2 gas sensor using SAW device based on ZnO film has good response characteristics to different concentrations CO2 gas. Furthermore, the CO2 gas sensor using SAW device based on ZnO film has good stability and linearity.


Sign in / Sign up

Export Citation Format

Share Document