Case Studies and Its Commercial Application

In this chapter, we propose to highlight case studies of two valuable chemicals which are being produced in bulk throughout the world 

Para Toluene Sulphonic Acid widely used as plasticizers, additive in foundry chemicals, production of cresols, additive in detergents as sodium salts and other chemical reactions. These are outlined as below - 

Production of Raw material to manufacture saccharine namely otho toluene sulphonamine. The byproduct is para toluene sulphonic chloro amine— T for water purification. 

At present the world production of Saccharine is in the range of 6000-8000 tonnes/year. The world requires minimum of 100,000 tonnes of Chloro Sulphonic Acid for sulphonation of toluene, a series of batch reactors requiring chilling unit for better conversion of toluene orther isomer. It will also produce 150,000 tonnes of hydro chloric acid (commercial grade 30 %) the innovative process will avoid the above drawbacks in the current manufacture and thereby produce saccharine at much cheaper price. 

Advances in Sulphonation Techniques, SpringerBriefs in Applied Sciences and Technology, DOI 10.1007/978-3-319-22641-5 9 

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In many cases, the racemization of a substrate required for DKR is difficult As an example, the production of optically pure cc-amino acids, which are used as intermediates for pharmaceuticals, cosmetics, and as chiral synfhons in organic chemistry [31], may be discussed. One of the important methods of the synthesis of amino acids is the hydrolysis of the appropriate hydantoins. Racemic 5-substituted hydantoins 15 are easily available from aldehydes using a commonly known synthetic procedure (Scheme 5.10) [32]. In the next step, they are enantioselectively hydrolyzed by d- or L-specific hydantoinase and the resulting N-carbamoyl amino acids 16 are hydrolyzed to optically pure a-amino acid 17 by other enzymes, namely, L- or D-specific carbamoylase. This process was introduced in the 1970s for the production of L-amino acids 17 [33]. For many substrates, the racemization process is too slow and in order to increase its rate enzymes called racemases are used. In processes the three enzymes, racemase, hydantoinase, and carbamoylase, can be used simultaneously this enables the production of a-amino acids without isolation of intermediates and increases the yield and productivity. Unfortunately, the commercial application of this process is limited because it is based on L-selective hydantoin-hydrolyzing enzymes [34, 35]. For production of D-amino acid the enzymes of opposite stereoselectivity are required. A recent study indicates that the inversion of enantioselectivity of hydantoinase, the key enzyme in the... 

Many aspects of substitution, its conditions and effects already described in existing subject literature were confirmed in the course of work on the case studies, but this was mostly only in certain cases and without any systematic framework for interpretation. This includes the enforcement deficit for application-related regulations in small and medium-sized enterprises, the obstractive behaviour of powerful associations or the trend towards more public attention with regard to substances in consumer products - in comparison with commercially used preparations or substances. 

There have been many studies on the application of membrane technology to food Industries. Few have, however, reached a commercial success except those of dairy processes (1) DAICEL has been studying since 1971 the application of its cellulose acetate RO membranes and polyacrylonitrile UF membranes to food, pharmaceutical, medical, paper and other industries. As to the use of membranes in food industries other than dairy processes, only two cases were developed to a semicommercial scale, that is, grape juice concentration for wine must and tomato juice concentration for processing and storage of the juice till next harvest. 

The most versatile carbene precursors are a-diazocarbonyl compounds such as diazoacetic acid esters because they are readily prepared, easy to handle and much more stable than ordinary diazoalkanes [10,38]. Nevertheless, one should always be aware of the potential hazards of diazo compounds in general [39],but if the necessary precautions are taken, they can be safely handled even on an industrial scale [18]. The most frequently used reagent is commercially available ethyl diazoacetate. Besides a-diazocarbonyl reagents, diazomethane [40,41 ] and a y-diazoacrylate derivative [42] have been used in enantioselective Cu-cata-lyzed cyclopropanations but the scope of these reactions has not been studied systematically. It has been shown in certain cases that diazo compounds can be replaced by other carbene precursors such as iodonium ylides, sulfonium yUdes, or lithiated sulfones [8,43],but successful applications of these reagents in enantioselective Cu-catalyzed reactions have not been reported yet. 

At a minimum, documentation of the characterization and stability of a standard, such as a certificate of analysis (Co A) and/or a certificate of stability (CoS), is typically available from the suppliers. The certificate should be obtained and recorded. The quantity of reference standard is typically limited in commercial kits designed for research use, and it is not uncommon that the reference material values may differ substantially between lots and manufacturers [16]. Novel biomarkers rarely have established gold standards against which their potency and abundance can be calibrated. A comparison of available sources can be useful, and when validating an assay for advanced applications it is desirable to plan ahead to obtain and reserve a sufficient supply of the same reference material. The example in Fig. 6.5 compares three reference standard curves, each prepared from a concentrated stock solution from a commercial supplier, an in-house reference standard, and a commercial kit, respectively. The instrument responses (optical density, OD) were highest with the standard from the commercial stock, the lowest with the kit, while the in-house reference standard response was intermediate. In this case, either the same commercial stock or the in-house reference standard can be used throughout the clinical study. 

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