Novel solid acids

Another recent new application of a microporous materials in oil refining is the use of zeolite beta as a solid acid system for paraffin alkylation [3]. This zeolite based catalyst, which is operated in a slurry phase reactor, also contains small amounts of Pt or Pd to facilitate catalyst regeneration. Although promising, this novel solid acid catalyst system, has not as yet been applied commercially. 

Matsuo, Y., Saito, K., Kawashima, H., Ikehata, S. (2004). Novel solid acid fuel cell based on a superprotonic conductor Tl3H(S04)2- Solid State Comm. 130,411-414. 

ExSact Novel Solid-Acid Catalyzed Iso-Paraffin Alkylation Process... 

Hu, R.-J. and Li, B.-G. 2004. Novel solid acid catalyst, bentonite-supported polytrifluoromethanesulfosiloxane for Friedel-Crafts acylation of ferrocene. Catal. Lett. 98 43 7. 

P-12 - Partially crystalline zeolitic material as novel solid acid catalysts... 

Nanostructured Metal Oxide Solid Acids Development of novel solid acid catalysts is of great importance to open up the possibility of new reactions. Nanostructured materials such as 2D nanosheets, ID nanotubes, and also 3D porous metal oxides have been newly synthesized and applied for acid-catalyzed reactions. 

Krishnakumar, B., Swaminathan, M. 2011. Solvent free synthesis of quinoxalines, dipyrido-phenazines and chalcones under microwave irradiation with sulfated Degussa titania as a novel solid acid catalyst Journal of the Molecular Catalysis A Chemical 350 16. 

Finally, aiming at making novel solid acid based technologies more attractive for refiners, special attention has been devoted to preserve a considerable... 

Despite the significant work reported in the literature for these materials, there are few examples of the synthesis of zirconium phosphonates containing pendant acid groups and then-utilization as ion exchangers or as solid catalysts [refs. 5-8]. The ability to incorporate specific pendant functional groups into MELS provides opportunities for the development of several classes of novel solid acid catalysts. This paper provides an introduction to MELS materials, a description of synthetic methods used to produce solid MELS catalysts containing pendant sulfonic acid groups, and a discussion of some of the physical and catalytic properties of these materials. 

Examples of commercially applied solid base catalysts are much fewer than for solid acids. Nevertheless, much attention is currently focused on the development of novel solid base catalysts for classical organic reactions such as aldol condensations, Michael additions, and Knoevenagel condensations, to name but a few. 

Biodiesel can be produced by a sustainable continuous process based on catalytic reactive distillation. The integrated design ensures the removal of water byproduct that shifts the chemical equilibrium to completion and preserves the catalyst activity. The novel alternative proposed here replaces the liquid catalysts with solid acids, thus dramatically improving the economics of current biodiesel synthesis and reducing the number of downstream steps. The key benefits of this approach are ... 

Mat Robinson was born in Malvern he graduated from the University of Wales Swansea with a first class M.Chem. degree in 2004. He is also currently studying there for his Ph.D. under the supervision of Dr. Andy Graham. His research interests include the development of novel solid Lewis and Bronsted acids, nanomaterials, and rearrangement reactions in natural product synthesis. 

A novel mesoporous intercalate belonging to the class of mesostructured solid acids known as porous clay heterostructures (PCH) has been synthesized through the surfactant - directed assembly of silica in the two - dimensional galleries of saponite. The new saponite PCH, denoted SAP-PCH, exhibits a basal spacing of 32.9 A, a BET surface area of 850 m2/g and pore volume of 0.46 cm3/g. SAP-PCH is an effective catalyst for the condensed phase Friedel-Crafts alkylation of bulky 2,4-di-tert-butylphenol (DBP) with cinnamyl alcohol to produce a large flavan, namely, 6,8-di-tert-butyl-2,3-dihydro[4H]benzopyran. 

Key trends for novel, environmentally more benign, processes are (i) replacement of stoichiometric processes by catalytic ones, (ii) process steps with 100% conversion and 100% selectivity (iii) the highest possible substrate concentration (iv) environmentally acceptable solvents with few solvent changes (v) avoidance of buffers and salt production, but instead use of solid acids and bases and pH-stat techniques. Examples of novel processes included in the discussion are ... 

Shiva Kesava Raju, Ch. Subramanian, M.S. Sequential separation of lanthanides, thorium and uranium using novel solid phase extraction method from high acidic nuclear wastes, J. Hazard. Mater. 145 (2007) 315-322. 

The adaptation of this procedure in solid phase allows expansion of the easy and automated access to novel glycosylamino acid building blocks required for chemical libraries construction, not only by convergent, but also by stepwise, methods. 

Recently, we found that a new class of solid acid catalyst, a Nafion resin/silica nanocomposite effectively catalyzes the Pechmann reaction (65). Nafion resin is a tetrafluoroethylene and perfluoro-2-(fluorosulfonylethoxy)propyl vinyl ether copolymer and can be made more suitable for organic catalysis. In the novel nanocomposites of Nafion resin, the nanometer-sized Nafion particles are entrapped within a porous silica matrix. These materials combine the excellent solid-acid... 

Mechanical methods of the activation of chemical processes are cnrrently widely nsed for the synthesis of various compounds. The present monograph deals with the development of a novel approach to mechanochemical synthesis based on reactions of solid acids, bases, hydrated compounds, crystal hydrates, basic and acidic salts. This method has been called soft mechanochemical synthesis. 

Toshima, K, Kasumi, K, Matsumura, S, Novel stereocontrolled glycosidations of 2-deoxyglucopyranosyl fluoride using a heterogeneous solid acid, sulfated zirconia (SO4/Z1O2), Synlett, 813-815, 1999. 

Nagai, H, Kawahara, K, Matsumura, S, Toshima, K, Novel stereocontrolled a- and p-glycosidations of mannopyranosyl sulfoxides using environmentally benign heterogeneous solid acids. Tetrahedron Lett, 42, 4159-4162, 2001. 

Georga, K.A. Samanidou, V.F. Papadoyannis, l.N. The use of novel solid phase extraction sorbent materials for HPLC quantitation of caffeine metabolism products methyl-xanthines and methyluric acids in samples of biological origin. J. Chromatogr., B 2001, 759, 209 -218. 

Broxterman, H. J., Schuurhuis, G. J., Lankelma, J., Oberink, J. W., Eekman, C. A., Claessen, A. M. E., Hoekman, K., Poot, M., and Pinedo, H. M. (1997) Highly sensitive and specific detection of P-glycoprotein function for hematological and solid tumor cells using a novel nucleic acid stain. Br. J. Cancer 76, 1029-1034. 

Besides the above CD processes, some of the recent novel applications of CD are outlined below. The production of amines from the hydrogenation of aniline and the selective production of diethanolamine from the reaction of monoethanolamine and ethylene oxide have been reviewed. A patent on the production of phenol from cumene hydroperoxide disclosed that solid acid catalysts such as zeolites, ion-exchange resins achieved 100% conversion with about 60 /o selectivity to phenol at 50-90°C and 0-10 psig. This process utilizes the heat of the decomposition of cumene hydroperoxide to effect the separation of the lower boiling components and hence reduces the energy cost and carbon dioxide emissions. 

---