Hydration/hydrolysis

Water activity, see also Hydration Hydrolysis Hydrometry Hydrophobicity Water content Water retention constraints of, 37-38 defined, 51... 

Hydrolysis and hydration—Hydrolysis of functional groups present in Mannich bases is best carried out under acidic conditions in order to improve the stability of the base. Hydrazine has been used in the hydrolysis of phthaiimidc derivatives to obtain products having a primary amino group (see also Fig. 15, Chap. I). The triple bond of acetylenic Mannich bases has been subjected to the addition of water in the presence of mercury salts with the aim of producing P- abed aminoketoncs (Table 30). 

HPAB Hanssons Pyrotekniska Hx hydroxy hydrated, hydrolysis... 

Fe(OH)2 is prepared from Fe° solutions by precipitation with alkali. When freshly precipitated under an inert atmosphere (in a Schlenck apparatus for example) Fe(OH)2 is white (Bernal et al., 1959). It is, however, readily oxidized by air or even water upon which it darkens. Fe(OH)2 has the CdL type structure with hep anions and half of the octahedral interstices being filled with Fe ions. The crystals form hexagonal platelets. In solution Fe(OH)2 transforms by a combination of oxida-tion/de-hydration/hydrolysis reactions to other iron oxides and hydroxides. The end product depends both upon the order in which these processes occur and upon their rates. 

The first commercial and most well-known application of CD was in the production of MTBE. Besides etherification for the production of MTBE, CD could be applied in a number of processes such as alkylation, hydrogenation, isomerization, esterification, desulfurization, aldol condensation, oligomerization, hydration, hydrolysis, amination, and halogenation. Catalytic Distillation Technology (CDTECH), a partnership between ABB Lummus Global and Chemical Research and Licensing, is the leader in the development and commercialization of CD processes particularly related to the refining, petrochemical, and chemical industries. However, there are many more potential applications of CD that could be developed. 

Complex-formation (hydration, hydrolysis, association, dissociation) Concentration of basis components C, r m,i Full stability constants, K. c.)... 

General acid Decomposition of acetaldehyde hydrate Hydrolysis of o-esters Formation of nitro componnd CH3CH(0H)2 = CH3CHO + H2O HC (0C2H5)3 -I- H2O = H COOC2H5 + 2C2H5OH CH2 N02 -I- acid = CH3-N02 + base ... 

Izumi, Y. 1997. Hydration/hydrolysis by solid acids. Catalysis Today 33(4) 371-409. 

As a final reaction mechanism catalyzed by water, we consider the hydration/hydrolysis reaction of an imine, CH2NH. The reaction energetics are shown in Fig. 8. As a simple bimolecular reaction, the four-centered addition transition state structures leading to hydration and hydrolysis have high activation barriers. The presence of an additional water molecule, providing six-centered transition state structures, lowers the barrier heights significantly. It should be noted that the hydrated form of the imine is the more stable form of the imine in aqueous solutions, as indicated in Fig. 8. This is also true of formaldehyde, for which the hydrated form, CH2(0H)2, is the more stable. 

A. Interaction of Solid with Water Hydration, Hydrolysis, Dissolution, and Dissociation... 

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