Sodium powder wetting

High Surface Sodium. Liquid sodium readily wets many soHd surfaces. This property may be used to provide a highly reactive form of sodium without contamination by hydrocarbons. Powdered soHds having a high surface area per unit volume, eg, completely dehydrated activated alumina powder, provide a suitable base for high surface sodium. Other powders, eg, sodium chloride, hydride, monoxide, or carbonate, can also be used. 

All lnaphthalenesulfonic Acids. The aLkyLnaphthalenesulfonic acids can be made by sulfonation of aLkyLnaphthalenes, eg, with sulfuric acid at 160°C, or by alkylation of naphthalenesulfonic acids with alcohols or olefins. These products, as the acids or their sodium salts, are commercially important as textile auxiUaries, surfactants (qv), wetting agents, dispersants (qv), and emulsifying aids, eg, for dyes (qv), wettable powder pesticides, tars, clays (qv), and hydrotropes. 

Sodium fatty acid ester sulfonates are known to be highly attractive as surfactants. These have good wetting abiHty and exceUent calcium ion stabiHty as weU as high detergency without phosphates, and are used in powders or Hquids. They can also be used in the textile industry, emulsion polymerization, cosmetics, and metal surface fields. Moreover, they are attractive because they are produced from renewable natural resources and their biodegradabiHty is almost as good as alkyl sulfates (134—137). 

The conventional sulfur dye powder is made into a paste with a small amount of soft water and an alkah-stable wetting agent. Boiling for a few minutes in a strong solution of sodium sulfide reduces the dye. The dissolved dye is diluted to the requited dyebath volume. When dyeing pale shades, the final bath should contain at least 5 g/L sodium sulfide (60%), inrespective of the amount used to dissolve the dye. 

The main metallic impurities that contaminate the primary powder, due to chemical corrosion of the retort and other metal parts of the reactor, are Fe, Ni and Cr. From this point of view, reactors that are equipped with larger retorts usually provide better purity due to a relatively low ratio between the internal surface of the wet metal parts of the reactor and the total volume of the melt. Recent investigations on the decreasing of Fe, Ni and Cr impurities during the sodium reduction process were performed by Li [591]. It was shown that one of the most effective ways to reduce contamination of the product is to reduce the duration of time K2TaF7 is present in the reactor. 

A typical plot of torque versus amount of liquid (di-butyl-phthalate, DBT) added is given in Fig. 15 for a very porous sodium carbonate powder mixture. The increase in measured torque at around 25% by volume DBT and again at around 65 %, can easily be seen (the final decrease in torque upon the formation of the wet cake is not shown). These two points correspond to the condition under which the continuous network of bridges forms, at about 25% liquid present, and the formation of the dry paste, at around 65%, where enough binder is available to fill most internal voids. The amount of liquid in Fig. 15 is given as a fraction of the total volume of powder, instead... 

A. Oximinomalononitrile. Malononitrile (Note 1) (25 g., 0.38 mole) is dissolved in a mixture of 20 ml. of water and 100 ml. of acetic acid in a 1-1. round-bottomed flask equipped with a stirrer, a thermometer, and a powder funnel. The solution is cooled to —10° with a dry ice-acetone bath, and 50 g. (0.72 mole) of granulated sodium nitrite is added in approximately 2-g. portions over a 30-minute period while the temperature is maintained at 0° to —10°. After the addition is complete a wet ice bath is used to maintain the temperature below 5° while the mixture is stirred for 4 hours. Four hundred milliliters of tetrahydrofuran (Note 2) and 400 ml. of ether are added in separate portions, and the mixture is stored at —40° overnight. The mixture is filtered rapidly, and the solid is washed with a mixture of 200 ml. of tetrahydrofuran (Note 2) and 200 ml. of ether. The filtrate and washings are combined and concentrated by distillation to a volume of 250 ml. by the use of a water aspirator and a bath at 40° (Note 3). This solution of oximinomalononitrile is used directly in the next step. 

Is any substance identified as water reactive YES Sodium hydrosulfite is water reactive uncoated aluminum powder is DOT/UN Hazard Class 4.3, Dangerous When Wet... 

Isomerization of this cyclic disulfide (see above) affords the 1,2,4-thiadiazolidine (159), also obtainable directly from sodium methyl dithiocarbamate by conveying the wet, finely powdered salt under oxidative conditions through a pneumatic dryer.166 The production of alkyl (and phenyl) homologs by this procedure is claimed in the patent literature,166 but no physical constants are given. It is recalled that the isomerization 158->159 had previously been thought to be confined to the methyl homologs.160,164... 

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