Catalysis clays

Hydration and Dehydration. Succinic anhydride reacts slowly with cold water and rapidly with hot water to give the acid. For this reason it must be carefully stored in anhydrous conditions. Succinic acid can be dehydrated to the anhydride by heating at 200°C, optionally in the presence of a solvent (31). Dehydration can also be performed with clay catalysis in the presence of isopropenyl acetate under microwave irradiation (32) or with his (trichi oromethyl) carbonate at room temperature (33). 

Vaccari A. Clays and Catalysis a Promising Future Appl. Clay Sci. 1999 74161-198 Keywords cationic and anionic clays, catalysis... 

Another type of reaction that responds to WD cycles is the fixation of K and NH4 ions by smectite (3-7). The fixation of K in smectite has been studied extensively by soil scientists because of its effect on the availability of plant nutrients. The reaction also decreases smectite s ability to swell, decreases its cation exchange capacity (CEC), and modifies its BrjSnsted acidity. Therefore, an understanding of this phenomenon is applicable to many fields of study that are concerned with swelling clays, fields such as soil fertility, soil mechanics, waste disposal, clay catalysis, and the geochemistry of ground and surface waters. 

Rode, B. M., Son, H. L. and Suwannachot, Y. (1999). The combination of salt induced peptide formation reaction and clay catalysis a way to higher peptides under primitive earth conditions. Orig. Life. Evol. Biosph., 29, 273-86. 

A kinetic study (52) of the redistribution of bridging oxygen occurring in mixtures of hexamethyldisiloxane and octamethylcyclotetrasiloxane by gas chromatography has been reported recently. At 80° C with acid-clay catalysis, equilibrium is reached within 3 to 17 hours. Early and prominent maxima for =4 and 8 in (CH3)3Si0[Si(CH3)20] Si(CH3)3, indicate that the following net reactions are initially important ... 

Heller-Kallai, L. 2002. Clay catalysis in reactions of organic matter. In Organo-clay complexes and interactions, ed. S. Yariv, H. Cross, 567-613. New York Marcel Dekker. Herbelin, A. L., and J. C. Westall. 1996. FITEQL3.2, A Program for the Determination of Chemical Equilibrium Constants from Experimental Data. Corvallis Oregon State University. 

Figure 3.6 Formation of 2,4-D esters using clay catalysis...

Collet, C. and P. Laszlo. 1991. Clay catalysis of the non-aqueous Diels-Alder reaction and the importance of humidity control. Tetrahedron Lett. 32 2905-2908. 

Degradation of poly(ethylene terephthalate)/clay nanocomposites during melt extrusion Effect of clay catalysis and chain extension. Polymer Degradation and Stability. Vol.94, pp.113-123. 

Ming-Yuan, H., Zhonghui, L. and Enze, M., 1988. Acidic and Hydrocarbon Catalytic Properties of Pillared Clays. Catalysis Today, 2 321. 

Wright, A. C., Grandquist, W. T., and Kennedy, J. V. 1972. Catalysis by layer lattice silicates. I. The structure and thermal modifications of a synthetic ammonium dioctahedral clay. /. Catalysis 25 65-80. 

Tong-Shuang, L., Zhan-Hui, Z., Feng, Y, Cheng-Gaung, F. 1998. MontmorUlonite clay catalysis. Part 7. An environmentally friendly procedure for the synthesis of coumarins via Pechmann condensation of phenols with ethyl acetoacetate. J. Chem. Res. 38-39. 

TzouMS, Pinnavaia TJ (1988) In Burch R (ed) Pillared Clays, Catalysis Today 2 243 Heylen I,Vanhoof C,Vansant EF (1995) Microporous Mater5 53 Burch R, Warburton Cl (1978) J Chem Soc Chem Commun 117... 

Jones SL (1988) In Burch R (ed) PUlared Clays, Catalysis Today 2 2-3... 

H. Ming-Yuan, L. Zhonghui, and M. Enze, Acidic and hydrocarbon catalytic properties of pillared clay. Catalysis Today, 2 (1988), 321-38. 

D.E.W. Vaughan in R. Burch (Ed). Pillared clays a historical perspective, Vol 2 Elsevier. Pillared clays Catalysis today, 1988,... 

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