2-Ethoxyethanol solution, alkaline

A very pronounced synergistic effect is found for binary ruthenium-iron carbonyl catalysts in the water-gas shift reaction. Both mixed ruthenium-iron clusters and mixtures of ruthenium clusters with iron complexes are considerably more active in basic solutions. Whereas the water-gas shift activity (moles of H2 per mole of complex per day) of alkaline aqueous ethoxyethanol solutions of Ru3(CO)12 and Fe(CO)j is... 

The first published report on the homogeneous catalysis of the WGSR by soluble transition metals complexes in alkaline solutions was based on the use of Ru3(CO)i2 in aqueous 2-ethoxyethanol solutions of KOH under 1 atm CO at 100°C (13). This was immediately followed by a report that related metal carbonyl complexes are active for WGSR catalysis in the presence of amines (14). A large number of other transition metal carbonyl complexes have since been demonstrated to be active WGSR catalysts under basic conditions (17,18). 

A report in 1977 (3) of an active system prepared from [Rh(CO)2CI]2, CH3CO2H, cone. HC1 and Nal in water demonstrated that a basic medium is not a necessary condition for WGSR catalysis. This result stimulated us to examine the potential activity of several simple metal carbonyls in acidic solution as well. Attempts with Fe(CO)5 and Iri (CO)12 (17), both active in alkaline and amine solutions, proved unfruitful. However Ru3(CO)12 in acidic (0.5 N H2SOtf) aqueous ethoxyethanol gave WGSR activity substantilly larger than found in basic solutions under otherwise analogous conditions (Pco=0.9 atm, T=100°C, [Ru]Total=0 036 mol/L) (15). This solution proved unstable and... 

Alkaline solutions of Ru(CO)t2 (KOH in aqueous ethoxyethanol) have also been found to catalytically decompose formic acid (5 7,5S). Presumably this occurs by way of anionic ruthenium hydride derivatives [e.g., HRu3(CO)7,] reacting with HCOOH to provide a ruthenium formate derivative and H2. Subsequent / -elimination of hydride from the ruthenium formate led to regenerating the anionic ruthenium hydride species and carbon dioxide. We have recently synthesized and fully characterized a possible ruthenium formato intermediate for this process, Ru3(CO),0-(02CH) (9) (59). Indeed this species in part extrudes C02 in the presence of CO with concomitant production of Ru3(CO),, H. ... 

A solution of 23 g. (0.25 mole) of aniline in 250 ml. of 2.5 iV hydrochloric acid is diazotized at 5° by the addition of 17.5 g. (0.25 mole) of sodium nitrite in 100 ml. of water. The resulting solution is added to a solution of 23 g. (0.27 mole) of dicyandiamide in 700 ml. of water at 20°. To this is added 10 N sodium hydroxide until the mixture is strongly alkaline and after it has stood 30 minutes it is acidified with acetic acid. The precipitated triazene (CeHsN NNHCfNHlNHCN) is removed by filtration, washed with water, and partially dried by suction on the filter. The solid is then added (15 minutes) with stirring to a mixture of 200 ml. of -ethoxyethanol and 28 ml. of 10 N hydrochloric acid held at 28-30°. After the mixture has been stirred for 1 hour at this temperature no more nitrogen is evolved and 500 ml. of water is added. The precipitated phenyldicyandiamide is dissolved in 250 ml. of boiling 1 N sodium hydroxide, filtered with activated carbon, and reprecipitated by the addition of dilute hydrochloric acid. The crystalline product weighs 20 g. and after recrystallization from methanol melts at 196-197°. 

Prof. Ford group did most of the research with the Ru-based complexes. In 1967, Laine from Prof. Ford group [5] evaluated Ru carbonyl catalysts in alkaline solution for the homogeneous WGS reaction for the first time. They mixed Ru3(CO)i2 with the KOH, H2O and ethoxyethanol and heated to 100 °C under 1 atm of CO. 

SPPO was first prepared by sulfonating PPO of intrinsic viscosity of 1.58 dL/g in chloroform at 2S C. Solutions of SPPOH in different solvents like ethoxyether and butoxyether were coated onto the surface of commercial polyethersulfone ultrafiltration membranes. All coated membranes were dried at 60° C for overnight. TFC membranes prepared from a solution of SPPO in ethoxyethanol demonstrated higher permeances and permeance ratios for CO2/CH4 gas pair. These membranes were immersed in solutions of alkali metal hydroxide or alkaline earth metal hydroxide of 0.1 to IN concentrations, depending on the solubility of the respective hydroxide in water. When the solubility was low, the solution saturated with hydroxide was used. The TFC membranes were kept immersed for 48 hours at room temperature to complete the exchange of the proton with metal cations. Solutions of magnesium nitrate and aluminium chloride were used to replace the proton with Mg and AF respectively. 

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