Oxygen removal of

Addition of oxygen, removal of hydrogen or loss of electrons. Oxygenation Treatment ... 

J.W. Davis, A.A. Haasz, Oxygen removal of codeposited a-C D layers from tokamak tiles, J. Nucl. Mater. 266-269 (1999) 478... 

As shown in Figure 17.1, the three required elements to sustain combustion include a source of fuel, heat, and oxygen. Removal of any one of these elements from the cycle can prevent combustion. It takes heat to initiate combustion (AH 1) and once combustion begins heat is liberated (AH 2). This would correspond to the total heat released as measured by cone calorimetry (see Section 17.8)... 

In the previous discussion, in all processes the reduction of the oxygen carrier and the removal of its (lattice) oxygen were always forced by the fuel, which in the previous cases was methane and occasionally carbon monoxide. One could think of a process utilizing reversibly oxidized and reduced carriers where the reduction (oxygen removal) of the carrier takes place by heating at elevated temperatures without the presence of a fuel in reactor 2. The reaction that takes place under such conditions in reactor 2 can be written as... 

Although supply of reactant gases in a static mode dining fuel cell operation is feasible, particularly using pure hydrogen and oxygen, removal of water requires special cell designs. 

Waste soybean and palm oils (by-product of the purification process of palm oil) were proposed for a single-step process to generate jet-fuel (aviation is responsible of 12% of CO2 emissions). Results showed a degree of oxygen removal of 95%, without using hydrogen, which are promising results for the sustainability of aviation transportation (Choi et al., 2015). 

Reduction was then defined as the removal of oxygen or the addition of hydrogen, whilst oxidation was the addition of oxygen or the removal of hydrogen. 

Beryllium is added to copper to produce an alloy with greatly increased wear resistance it is used for current-carrying springs and non-sparking safety tools. It is also used as a neutron moderator and reflector in nuclear reactors. Much magnesium is used to prepare light nieial allo>s. other uses include the extraction of titanium (p. 370) and in the removal of oxygen and sulphur from steels calcium finds a similar use. 

Reductive coupling of carbonyl compounds to yield olefins is achieved with titanium (0), which is freshly prepared by reduction of titanium(III) salts with LiAIH4 or with potassium. The removal of two carbonyl oxygen atoms is driven by T1O2 formation- Yields are often excellent even with sensitive or highly hindered olefins. (J.E. McMurry, 1974, 1976A,B). 

C—C double bonds may be protected against electrophiles by epoxidation and subsequent removal of the oxygen atom by treatment with zinc and sodium iodide in acetic acid (J.A. Edwards, 1972 W. Kndll, 1975). Halogenation has often been used for protection, too. The C—C double bond is here also easily regenerated with zinc (see p. 138, D.H.R. Barton, 1976). 

Chemical conversion processes can also be used for moisture and oxygen removal. These tend to be the same ones developed for the smaller point-of-use purifiers. Consequently there is Httle economy of scale and they are seldom able to be regenerated. 

In normal practice, inhibitors such as hydroquinone (HQ) [123-31 -9] or the monomethyl ether of hydroquinone (MEHQ) [150-76-5] are added to acrylic monomers to stabilize them during shipment and storage. Uninhibited acrylic monomers should be used prompdy or stored at 10°C or below for no longer than a few weeks. Improperly iahibited monomers have the potential for violent polymerizations. HQ and MEHQ require the presence of oxygen to be effective inhibitors therefore, these monomers should be stored in contact with air and not under inert atmosphere. Because of the low concentration of inhibitors present in most commercial grades of acrylic monomers (generally less than 100 ppm), removal before use is not normally required. However, procedures for removal of inhibitors are available (67). 

This principle is illustrated in Figure 10 (45). Water adsorption at low pressures is markedly reduced on a poly(vinyhdene chloride)-based activated carbon after removal of surface oxygenated groups by degassing at 1000°C. Following this treatment, water adsorption is dominated by capillary condensation in mesopores, and the si2e of the adsorption-desorption hysteresis loop increases, because the pore volume previously occupied by water at the lower pressures now remains empty until the water pressure reaches pressures 0.3 to 0.4 times the vapor pressure) at which capillary condensation can occur. 

---