Incoming starting materials

Traceability within stakeholders operations Incoming starting materials... 

To attain a suitable level of traceability, each business operator must ensure that the incoming starting materials that he uses are supplied with information from the relevant supplier in order to ensure full and unequivocal identification of the starting material to be made. In the case of a converting or producing operation, such information should include ... 

A record should be make of ail incoming starting materials. The record should contain information on the supplier, the origin (if possible), lot number, date of receipt, date of release and date of expiry (if any). 

Petroleum refineries produce a stream of valuable aromatic compounds called the BTX, or benzene-toluene-xylenes (Ruthven 1984). The Cg compounds can be easily separated from the Ce and C compounds by distillation, and consist of ethyl benzene, o-xylene, m-xylene, and / -xylene. Ethyl benzene is the starting material for styrene, which is used to make polystyrene / -xylene is oxidized to make terephthalic acid, and then condensed with ethylene glycol to make polyester for fibers and films. The buyers of / -xylene are the manufacturers of terephthalic acid, such as BP-Amoco, who in turn sell to the fiber manufacturers such as DuPont and Dow. These are big and sophisticated companies that have strong research and engineering capabilities, and are used to have multiple suppliers. The eventual consumers of adsorbents are the public who consider polyester as one of the choices in fabric and garments, in competition with other synthetic and natural fibers. Their purchases are also dependent on personal income and prosperity. In times of recession, it is always possible for a consumer to downgrade to cheaper fibers and to wear old clothes for a longer period of time before new purchases. 

Infrared spectroscopy, in the forms of both NIR and mid-IR spectroscopy, has been hailed as a major growth area for process analytical instruments.4,5 This view assumes that traditional laboratory instruments are outside of those covered by the areas concerned. Overall, this has been difficult to define in terms of the boundaries between the laboratory and the process where they start and end. Some of the confusion arises by the term process analysis itself. In the most liberal form, it can be considered to be any analysis that is made within an industrial environment that qualifies a product. This ranges from the QC of incoming raw materials, to the control of the manufacturing process through its various intermediate stages, and on to the analysis of the product. How this is viewed is very much industry-dependent. 

This approach is fairly general. Let us assume that a reaction product contains a bond which is sufficiently weak to break spontaneously. If this is the bond formed by the incoming reagent, the reaction will be reversible. If it is one of the bonds present in the starting material, the reaction will evolve to give a new product and we have a multi-step mechanism. 

Having established the three-dimentional structure of carbocations as planar, we can now study the stereochemical progression of Sk 1 reactions as compared to Sk2 reactions. As shown in Scheme 5.6, the stereochemical course of an Sk2 reaction is well defined because nucleophilic displacement of a leaving group proceeds with inversion of stereochemistry. Thus, the stereochemical outcome is defined by the stereochemistry of the starting material. As for SnI reactions, since the step required for initiation of these reactions involves formation of a planar species, incoming nucleophiles have equal access to both sides of the reactive carbocation. As shown in Scheme 5.7, this results in complete elimination of... 

Under such arrangements, it is possible that a validated procedure exempting identity testing of each incoming container of starting material could be accepted for ... 

Incoming materials, part-processed or finished products from contract acceptors should be treated and documented as for Starting Materials. 

Figure 3.10, once the carbon-oxygen bond of the starting material has been broken, the incoming nucleophile can add to either the same carbon atom which carried the original substituent, or to the one at the opposite end of the allylic system. The exact course of the reaction will be determined by the reagents and the reaction conditions. 

---