Gas reduction

Gas Reduction. The use of a gaseous reduciag agent is attractive because the metal is produced as a powder that can easily be separated from the solution. Carbon dioxide, sulfur dioxide, and hydrogen can be used to precipitate copper, nickel, and cobalt, but only hydrogen reduction is appHed on an iadustrial scale. In the Sherritt-Gordon process, the excess ammonia is removed duting the purification to achieve a 2 1 ratio of NH iNi ia solution. Nickel powder is then precipitated by... 

Sulfur Dioxide Reductant. The Mathieson process uses sulfur dioxide, sodium chlorate, and sulfuric acid to produce chlorine dioxide gas with a much lower chlorine content. The sulfur dioxide gas reductant is oxidized to make sulfuric acid, reducing the overall acid requirement of the process. Air is used to dilute the chlorine dioxide produced by this process. The exit gases flow through a scmbber to which chlorate is added in order to remove any unreacted sulfur dioxide. Spent Hquor, containing some unreacted chlorate, sulfuric acid, and sodium sulfate, continuously overflows from this process. 

Chianese, D. S., Rotz, C. A., and Richard, T. L. (2009b). Simulation of carbon dioxide emissions from dairy farms to assess greenhouse gas reduction strategies. Trans. ASABE 52,1301-1312. 

Herzog, H., CO, sequestration. Proc. Greenhouse Gas Reduction Programs and Technologies Symp., Dedham, MA, 2002. 

The same authors also reported the dispersion of palladium nanoparticles in a water/AOT/n-hexane microemulsion by hydrogen gas reduction of PdClJ and its efficiency for hydrogenation of alkenes in organic solvents [79]. UV-visible spectroscopy and TEM analysis revealed the formation of Pd nanoparticles with diameters in the range of 4 to 10 nm. Three olefins (1-phenyl-l-cyclohexene, methyl trans-cinnamate, and trans-stilbene) were used as substrates for the catalytic hydrogenation experiments under 1 atm of H2 (Table 9.12). All of the Start-... 

Hydrogen fuel-based technologies hold great promise in reducing carbon dioxide and toxic air emissions from mobile sources in meeting current clean air standards and proposed greenhouse gas reductions. 

The natural gas after appropriate treatment for acid gas reduction, odorization, and hydrocarbon and moisture dew point adjustment (ASTM D1142) would then be sold within prescribed limits of pressure, calorific value, and possibly, the Wobbe Index [(calorific value)/(specific gravity)]. 

Biofuels offer a number of technical and enviromnental benefits over conventional fossil fuels, which make them attractive as alternatives for the transport sector. The benefits include greenhouse gas reductions including reduced carbon dioxide emissions, which will contribute to domestic and international targets, the diversification of the fuel sector, biodegradability, sustainability, and an additional market for agricultural products. Biofuels help to protect and create jobs. Table 3.1 shows the major benefits of biofuels. 

In the future, biomass has the potential to provide a cost-effective and sustainable supply of energy, while at the same time aiding countries in meeting their greenhouse gas reduction targets. By the year 2050, it is estimated that 90% of the world population will live in developing countries. 

Table 9.2.4 Chemical Analysis of Two Cobalt Powders Obtained from the Same Parent Hydroxide by Solid-Gas Reduction and by the Polyol Process (Main Impurities/ Cobalt Ratios in ppm by Weight)...

CofOH) (precursor) Co (solid-gas reduction) Co (polyol process)... 

The Union Oil selective sulfur oxidation catalyst is the basis for many modified sulfur plant designs announced in recent years 7>18. This system may be ideal for a synfuels facility because of the low H2S/CO2 ratio of synfuel raw-gas streams. If a physical solvent is employed for acid-gas removal, some hydrocarbon will be lost to the acid-gas stream. With the selective sulfur oxidation catalyst, this fuel is not oxidized, rather it is available for tail-gas reduction over cobalt-molybdenom, prior to final treatment. 

M. Dyck, M. Fairlie, R. S. Me Millan, and V. Scepanovic, Hydrogen Systems A Canadian Opportunity for Greenhouse Gas Reduction and Economic Growth . Paper presented at the EIC Climate Change Technology Conference, Ottawa, Canada, May (2006). 

Based on the "idealized objectives" outlined in Table XIIL, we can arrive at the following catalyst characteristics for optimum coke and gas reduction... 

Greenhouse Friendly . This is a product certification programme where the company needs to demonstrate how all emissions from the production and use of the product have been offset by other greenhouse gas reduction programmes being conducted by the company. A full life cycle assessment of all greenhouse gas emissions associated with the product needs to be conducted. 

This technique is called in situ gas reduction (ISGR) which is easier and cheaper to apply than other treatments such as liquid phase extraction or excavation. 

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