Hydrogen evolved during

Used particularly for ethers. Cannot be used for any compound affected by alkalis, or easily subject to reduction (owing to the hydrogen evolved during dehydration). 

Metallic sodium. This metal is employed for the drying of ethers and of saturated and aromatic hydrocarbons. The bulk of the water should first be removed from the liquid or solution by a preliminary drying with anhydrous calcium chloride or magnesium sulphate. Sodium is most effective in the form of fine wire, which is forced directly into the liquid by means of a sodium press (see under Ether, Section II,47,i) a large surface is thus presented to the liquid. It cannot be used for any compound with which it reacts or which is affected by alkalis or is easily subject to reduction (due to the hydrogen evolved during the dehydration), viz., alcohols, acids, esters, organic halides, ketones, aldehydes, and some amines. 

These reactors were employed for coupling of isopentcnes dehydrogenation into isoprene with toluene hydrodemethylation. Hydrogen evolved during the first reaction in one compartment dissolved in palladium alloy plates and penetrated through them to the other compartment, where the second reaction took place. 

Besides the compact membrane catalysts described in Section II, there are two types of composite membrane catalyst porous and nonporous. Composite catalyst consists of at least two layers. The first bilayered catalyst was prepared by N. Zelinsky [112], who covered zinc granules with a porous layer of palladium sponge. The sponge became saturated with the hydrogen evolved during hydrochloric acid reaction with zinc and at room temperature actively converted hydrocarbon iodates into corresponding hydrocarbons. 

A method for the determination of water in hquids, based on GC analysis of the hydrogen evolved during the reaction of water with calcium hydride, was described by Starshovet al. [83],... 

The grease base stocks have yielded broadly similar levels of hydrogen evolved during a test. Therefore only an example of typical behaviour is shown in figure 6 and the basic characteristics of the all grease tests are recorded in tables 5 to 7. 

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