Reducing agents carbon

Sodium is, like all other alkali metals, a very strong reducing agent (more reactive than lithium), which has extremely violent reactions with numerous compounds. It causes a large number of accidents. Sodium peroxide is a very reactive oxidant, which has violent interactions with reducing agents. Carbonates, and especially sodium hydroxide, are bases which react with acids (the reaction is aggravated by the formation of carbon dioxide). 

Zinc production follows a similar path to the iron and lead processes in which carbon monoxide from carbon is the reducing agent. Carbon (coke or charcoal) is blended with zinc oxide and fed to a retort. The boiling point of pure zinc is low ( 900°C), so as the carbon is burned to form CO, the direct reduction of the zinc oxide by CO will result in the direct volatilization of the zinc. Cooling the vapor will condense the zinc, which can then be cast into ingots or alloyed with other metals. 

Although the reducing agent—carbon—is very cheap, and carbon reduction was the early basis of tungsten powder production, so far none of the numerous carbothermic procedures has been established in the production of pure tungsten. 

From the very outset of molten carbonate fuel cell development, research workers were attracted by the fact that not only hydrogen but also carbon monoxide could be used as a reactant fuel (reducing agent). Carbon monoxide (the so-called water gas, a mixture of CO and H2) is readily obtained by the steam gasification of coal ... 

Carbon is oxidized to CO2 and H2SO4 is reduced to SO2. Similarly, hydrogen need not be the reducing agent. Carbon is in the above example and again in... 

Reagent chemicals (e.g. reducing agent carbonate barium salt HCl caustic) Assay ghr... 

The carbon-bromine bond Is the only reactive one under these conditions, and magnesium an excellent reducing agent. Carbon dioxide Is the only available electrophile. 

The reducticn of metal oxides is often accomplished using carbon monoxide as a reducing agent. Carbon (coke) and carbon dioxide are usually present, leading to the following reaction ... 

When carbon monoxide acts as a reducing agent, carbon dioxide is produced, for example with iron(iii) oxide (at high temperature) ... 

The reduction of sulphur dioxide with hydrogen, carbon or carhon compounds such as methane or carbon monoxide is also of industrial interest. These reactions require high temperatures or catalysts or both. They result in mixtures of elemental sulphur with hydrogen sulphide. If carbon or a carbon compound has been used as the reducing agent, carbon-containing species such as carbon dioxide, carbonyl sulphide and carbon disulphide will be formed as well. 

Andrews deration An important titration for the estimation of reducing agents. The reducing agent is dissolved In concentrated hydrochloric acid and titrated with potassium iodale(V) solution. A drop of carbon tetrachloride is added to the solution and the end point is indicated by the disappearance of the iodine colour from this layer. The reducing agent is oxidized and the iodate reduced to ICl, i.e. a 4-eiectron change. 

Reference to Figure 3.4 shows that the reduction is not feasible at 800 K. but is feasible at 1300 K. However, we must remember that energetic feasibility does not necessarily mean a reaction will go kinetic stability must also be considered. Several metals are indeed extracted by reduction with carbon, but in some cases the reduction is brought about by carbon monoxide formed when air, or air-oxygen mixtures, are blown into the furnace. Carbon monoxide is the most effective reducing agent below about 980 K, and carbon is most effective above this temperature. 

Lead(II) oxide is easily reduced to the metal when heated with a reducing agent such as hydrogen, carbon or carbon monoxide, for example ... 

The process of extraction requires first smelting (to obtain the crude metal) and then refining. In smelting, iron ore (usually an oxide) is mixed with coke and limestone and heated, and hot air (often enriched with oxygen) is blown in from beneath (in a blast furnace). At the lower, hotter part of the furnace, carbon monoxide is produced and this is the essential reducing agent. The reduction reactions occurring may be represented for simplicity as ... 

C2H5ONO + NaOH C2H5OH + NaNOa sodium nitrite. The second compound is nitroethane, C,H NO, of b.p. 114° its identity is clearly shown by the action of reducing agents, which convert it into ethylamiiie, CjHjNHj, thus proving the presence of a nitrogen carbon... 

Triethylammonium formate is another reducing agent for q, /3-unsaturated carbonyl compounds. Pd on carbon is better catalyst than Pd-phosphine complex, and citral (49) is reduced to citronellal (50) smoothly[55]. However, the trisubstituted butenolide 60 is reduced to the saturated lactone with potassium formate using Pd(OAc)2. Triethylammonium formate is not effective. Enones are also reduced with potassium formate[56]. Sodium hypophosphite (61) is used for the reduction of double bonds catalyzed by Pd on charcoal[57]. 

Formic acid is a good reducing agent in the presence of Pd on carbon as a catalyst. Aromatic nitro compounds are reduced to aniline with formic acid[100]. Selective reduction of one nitro group in 2,4-dinitrotoluene (112) with triethylammonium formate is possible[101]. o-Nitroacetophenone (113) is first reduced to o-aminoacetophenone, then to o-ethylaniline when an excess of formate is used[102]. Ammonium and potassium formate are also used for the reduction of aliphatic and aromatic nitro compounds. Pd on carbon is a good catalyst[103,104]. NaBH4 is also used for the Pd-catalyzed reduction of nitro compounds 105]. However, the ,/)-unsaturated nitroalkene 114 is partially reduced to the oxime 115 with ammonium formate[106]... 

Potassium perchlorate Aluminum plus magnesium, carbon, nickel plus titanium, reducing agents, sulfur, sulfuric acid... 

The principal material cost for the Chilean iodine producers is sulfur used for the manufacture of sulfur dioxide, the reducing agent for the iodates contained in the leach solutions. Also, the use of sodium carbonate for the neutralization of the depleted solutions is an important cost factor. 

At reduction temperatures below about 1000°C, the reducing agents usually ate restricted to CO and Above about 1000°C, solid carbon can... 

Process Chemistry. Manganese is combined with oxygen in its ores (see Table 3) and carbon is the most economical reducing agent for oxides. Therefore, the essential characteristics of manganese metallurgy is evident from examination of the interactions between manganese oxides and... 

This product is mainly used within the ferroalloy plant as the reducing agent in a silicothermic process to produce the low carbon grade of refined ferromanganese. 

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