Industrial selective oxidation technology

Recent trends and developments in industrial selective oxidation technology can be summarized as follows ... 

Selective dehalogenation of halopyridines is an important industrial process for the same reason that reduction of carboxylic acids, esters, amides, and nitriles are also important. There is a dearth of selective oxidation technologies whether by conventional or electrochemical methods. Therefore, many intermediate oxidation stage products are made by overoxidation, i.e., overhalogenation, followed by selective reduction. 

The need to conserve raw materials and enhance the yield of high-value products has led the petrochemical industry to rely increasingly on processes that involve catalytic selective oxidation. In turn, this reliance has led to the emergence of important new technologies in the past decade—processes that use selective catalytic oxidation now generate almost a quarter of all organic chemicals produced worldwide. 

Industrial Catalysts for Regio- or Stereo-Selective Oxidations and Reductions. A Review of Key Technologies and Targets... 

Notari summarizes the science and technology of catalysis by molecular sieves incorporating framework metal ions. The most important example in technology is Ti silicalite, a selective oxidation catalyst. Because the catalysts are crystalline materials, their structures are among the most well-known of any industrial catalysts, and catalytic sites such as Ti cations are identified. The work summarized in this chapter, almost all of it performed in just the preceding few years, gives an... 

Although cyclohexane oxidation dominates the market, because of cheaper raw materials, the hydrogenation of phenol remains competitive, offering better selectivity with fewer environmental and safety problems. In addition, this process allows efficient valorization of phenol-rich wastes from coal industries. Recently built plants make use of this technology, as reported by the engineering group Aker-Kvaerner (www.kvaerner.com, 2004). The availability of low-price phenol is the most important element for profitability. Besides the well-known cumene process, a promising route is the selective oxidation of benzene with N20 on iron-modified ZSM-5 catalyst [12]. In this way, the price of phenol may become independent of the market of acetone. 

M. Haruta, S. Tsubota, T. Hayashi, Method for selective oxidation of hydrocarbons by gold-titanium oxide containing catalysts, Japan Patent JP 2,615,432 (Publ. no. 08-127550), May 21,1996, To Agency for Industrial Science and Technology (AIST). 

Improvements of already existing oxidation processes are continuously made (in MAA manufacture, with the riser reactor by DuPont, or in oxychlorination, by Montecatini Technologic and ICI). In addition, and still more clearly demonstrating the dynamism of industrial catal5rtic oxidation, completely new catalysts are discovered, especially with the titanium silicalite which permits the synthesis of hydroquinone from phenol, selective epoxidations, oxidations of alcohols to aldehydes, and the manufacture of cyclohexanoneoxime. 

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