Sodium carriers

Figure 6.5 Cu/Cd dynamic selectivity at AHLM transport from the aqueous solution of their chloride salt mixtures (0.1 mol/kg Cu and 0.1 mol/kg Cd) to the sodium chloride strip solution (2.0 mol/kg sodium). Carrier 0.5 mol/kg PVSH in water. Membrane Tokayama Soda cation-exchange membrane CMS. From Ref. [7] with permission.

Alkylation of carboxylic acid esters Sodium carrier... 

V-Alkylation can also be carried out with the appropriate alkyl haUde or alkyl sulfate. Reaction of aniline with ethylene, in the presence of metallic sodium supported on an inert carrier such as carbon or alumina, at high temperature and pressure yields V/-ethyl- or /V,/V-diethylaniline (11). At pressures below 10 MPa (100 atm), the monosubstituted product predominates. 

Sodium is commonly shipped in 36- to 70-t tank cars in the United States. Smaller amounts are shipped in 16-t tank tmcks or ISO-tanks. Sodium is also available in 104- and 190-kg dmms, and in bricks (0.5—5 kg). A thin layer of oxide, hydroxide, or carbonate is usually present. Sodium is also marketed in small lots as a dispersion in an inert hydrocarbon, or produced in-process via high pressure injection into a pumped stream of inert carrier fluid, such as toluene or mineral oil. 

Agriculture. Most forages provide insufficient sodium for animal feeding and may lack adequate chloride. Thus salt supplementation is a critical part of a nutritionally balanced diet for animals. In addition, because animals have a definite appetite for salt, it can be used as a deflvery mechanism to ensure adequate intake of less palatable nutrients and as a feed limiter. Salt is an excellent carrier for trace minerals. Salt, either in loose form or as compressed blocks, can be mixed with feed or fed free-choice to improve animal health and productivity (see Feeds and feed additives). 

Phenylphenol was one of the earliest carrier-active compounds used industrially. Originally it was used as its water-soluble sodium salt (4). By lowering the pH of the dyebath, the free phenol was precipitated in fine form and made available to the fiber. However, proprietary Hquid preparations containing the free phenol are available that afford a greater ease of handling. 

Should be distd under reduced pressure under nitrogen and stored in the dark. Purified via the nitrosochloride [Waterman et al. Reel Trav Chim Pays-Bas 48 1191 7929]. For purification of optically active forms see Lynn [J Am Chem Sac 91 361 1919]. Small quantities (0.5mL) have been purified by GLC using helium as carrier gas and a column at 90 packed with 20 wt% of polypropylene sebacate on a Chromosorb support. Larger quantities were fractionally distd under reduced pressure in a column packed with stainless steel gauze spirals. Material could be dried with CaH2 or sodium, and stored in a refrigerator CaS04 and silica gel were not satisfactory because they induced spontaneous isomerisation. [Bates, Best and Williams 7 C/iem Soc 1521 7962.]... 

A regenerative absorbent consisting of the amorphous silica manufactured by the action of MCI on sodium silicate. Hard, glossy, quartz-like in appearance. Used in dehydrating and in drying and as a catalyst carrier. 

Thermal stabilization of polyolefins has been first demonstrated for low-molecular models-normal structure alkanes [29]. It has been shown that metallic sodium and potassium hydroxide with absorbent birch carbon (ABC) as a carrier are efficient retardants of thermal destruction of n-heptane during a contact time of 12-15 s up to the temperature of 800°C [130]. Olefins and nitrous protoxide, previously reported as inhibitors of the hydrocarbon thermal destruction, are ineffective in this conditions. 

Cracking of w-alkanes is effectively inhibited by metallic sodium and potassium hydroxide with ABC carrier even under pressure and over a long period of time (Table 2). 

Metallic sodium practically completely retards crecking of heptane and hexadecane over a period of 120 min at 500°C, and in presence of potassium hydroxide with ABC carrier a fraction of decomposed hydrocarbon amounts to 2.1% in case of heptane and to 3.1% for hexadecane. 

Carbonates and bicarbonates are used as lower alkalinity adjuncts or substitutes for hydroxide. It has been suggested that hydroxide/carbonate systems are more resistant to carbonation during spraying than hydroxide-only solutions. Powder products blended with light sodium carbonate are much less hygroscopic, and the carbonate can be a useful carrier for liquid additives, such as surfactants and solvents. 

Fig. 1. The relative selectivity of two mobile carriers. In both parts of the figure, the circles and squares represent the sodium and potassium ions transported, respectively. (Cited from Ref. 8))...

In outline the procedure consists of carefully weighing about 5-10 mg of sample on to a shaped piece of paper (Fig. 3.11c) which is folded in such a way that the tail (wick) is free. This is then placed in a platinum basket or carrier suspended from the ground-glass stopper of a 500 mL or 1 litre flask. The flask, containing a few millilitres of absorbing solution (e.g. aqueous sodium hydroxide), is filled with oxygen and then sealed with the stopper with the platinum basket attached. 

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