Lonza economic process

At present about 77% of the industrial hydrogen produced is from petrochemicals, 18% from coal, 4% by electrolysis of aqueous solutions and at most 1% from other sources. Thus, hydrogen is produced as a byproduct of the brine electrolysis process for the manufacture of chlorine and sodium hydroxide (p. 798). The ratio of H2 Cl2 NaOH is, of course, fixed by stoichiometry and this is an economic determinant since bulk transport of the byproduct hydrogen is expensive. To illustrate the scde of the problem the total world chlorine production capacity is about 38 million tonnes per year which corresponds to 105000 toimes of hydrogen (1.3 x I0 m ). Plants designed specifically for the electrolytic manufacture of hydrogen as the main product, use steel cells and aqueous potassium hydroxide as electrolyte. The cells may be operated at atmospheric pressure (Knowles cells) or at 30 atm (Lonza cells). 

A technical process was developed by Lonza for the Ir-catalyzed hydrogenation of an intermediate of dextromethorphan (Fig. 34.9) which was carried out on a > 100-kg scale [70]. Important success factors were ligand fine tuning and the use of a biphasic system chemoselectivity with respect to C=C hydrogenation was high, but catalyst productivity rather low for an economical technical application. Satoh et al. reported up to 90% ee for the hydrogenation of an intermediate of the antibiotic levofloxacin using Ir-diphosphine complexes. Best results were obtained with bppm and a modified diop in the presence of bismuth iodide at low temperature [71]. 

Economic Aspects. Malononitrile is produced by Lonza Ltd. (Switzerland) using the cyanogen chloride process. 

For any type of process which can be developed on an industrial scale, one must be able to plan all sorts of scaling on the economical and t hnical points of view. For this reason plasma torch or plasma reactor modeling has become an important study. For example Lonza Corp has proposed a study of the relative costs of different plasma torches that we have actualized (Table 11). In this paper we present an outline of the main plasma devices used in the ceramics field. 

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