Ethylene over zinc oxide

Over zinc oxide it is clear that only a limited number of sites are capable of type I hydrogen adsorption. This adsorption on a Zn—O pair site is rapid with a half-time of less than 1 min hence, it is fast enough so that H2-D2 equilibration (half-time 8 min) can readily occur via type I adsorption. If the active sites were clustered, one might expect the reaction of ethylene with H2-D2 mixtures to yield results similar to those obtained for the corresponding reaction with butyne-2 over palladium That is, despite the clean dideutero addition of deuterium to ethylene, the eth-... 

Fig. 1. Arrhenius plots for hydrogenation rate of ethylene over nickel on doped zinc oxide.

The chief product is primary phosphine, which is liberated in a hydrogen-filled apparatus by slowly heating to boiling in a stream of hydrogen and pouring the boiling hquid into cold water. The oil which separates is primary phosphine and is dried over potassium hydroxide. (2) Ethylene dibromide, phosphonium iodide and zinc oxide are heated for six hours at 160° C. (3) One gram-atom of white phosphorus... 

Ethanol steam reforming catalysts were developed by Men et al. [24]. Nickel, rhodium and ruthenium catalysts on different carrier materials such as alumina, silica, magnesia and zinc oxide were tested at a S/C ratio of 1.5 and WHSV 90 Lh g J in the temperature range 400-600 °C. All the monometallic catalysts were mainly selective for acetaldehyde and ethylene. Over the rhodium catalyst, a reaction temperature of 600 °C was required to achieve 80% hydrogen selectivity. 

A stream of ethylene oxide is passed through a solution of 107 g of 2-(p-chlorophenoxy)-2-methylpropionic acid and 2 g of zinc chloride in 200 ml of toluene, previously heated to between 55°C and 60°C, until 24 g of the gas have been dissolved. The reaction is allowed to continue for five hours, with gentle stirring. After this time has elapsed, the solution is cooled and washed successively with water, dilute ammonia and water until its pH becomes neutral. It is dried over anhydrous sodium sulfate, the solvent Is separated off under vacuum, and the resulting liquid is the monoglycol ester of 2-(p-chlorophenoxv)-2-methylpropionlc acid. 

References may be found in the literature to attempts made for the purpose of reacting ethylene in a variety of other ways to obtain useful products. Condensation and oxidation products are claimed to lie formed when ethylene mixed with steam, ammonia, or hydrogen sulfide is passed over catalysts at high temperatures.811 Unsuccessful attempts have been made to obtain acetone by reacting ethylene with hydrogen and carbon monoxide in a molal ratio of 1 2.5 1, respectively, at 300° C. and 150 to 250 atmospheres pressure in the presence of a basic zinc chromate catalyst. In this case methanol was formed, a portion of the ethylene polymerized, and a portion was reduced to ethane.888 No acetone was formed. 

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