Suppliers solvents

Supplier Amersham Biosciences Depending on used organic solvent Supplier BioRad... 

Furthermore, sometimes a change of solvent supplier or lot could cause issues of stability for an internal standard and therefore IS response variations. For example, Napoli reported unusual IS response variation and stability problem when a different lot of acetonitrile was used for the preparation of ascomycin working solution (as the internal standard for tacrolimus, [43]). 

Solvent selection, as such, requires not only knowledge of solution behavior, but also of environmental regulations, solvent viscosity, flash point, odor, etc. Most major solvent suppliers and many larger companies have computer programs to help find optimum solvents. Cohesion energy parameter calculations based on the equations above are central in programs dealing with solvent selection."... 

Apolar solvents and polar impurities When a very apolar solvent is used as the eluent, a column can get completely blocked within a very short period of time by the introduction of small traces of a viscous polar substance (e.g., glycerol, dipropylene glycol), which are not soluble in the used solvent system. This might happen if for instance the filling equipment used to fill the drums has been insufficiently cleaned by the solvent supplier. Therefore, a thorough analysis of the incoming solvent batch is absolutely necessary. 

Water separators should have covers. All separators should be equipped with means for cooling the solvent to below the boiling temperature of the solvent-water azeotrope. Consult your solvent supplier for guidance. Make sure that the flow of the solvent condensate from the water-cooled condenser coils to the separator is unobstructed. 

A local solvent supplier has offered to buy any of the alcohols which meet the purity specifications shown below. He has quoted the following prices for tank tmck quantities ... 

We recommend working with reliable solvent suppliers who can give every assurance on the quality of solvents provided to avoid any unpleasant surprises . 

Many of the commonly known solvents are aetually petroleum distillation fractions and are eomposed of a number of compounds (e.g., mineral spirits and naphthas). There are two general types of solvents derived from petroleum, aliphatics or aromatics. Aromatics are stronger solvents than aliphatics since they dissolve a wider variety of resins. Most major solvent suppliers (chemical manufacturers) produee several types and variations of these solvents and the associated HAP contents can vary significantly from manufacturer to man-ufaeturer and from batch to batch. These types of solvents are used extensively and are present in the majority of marine coatings. Table 14.26.4 provides a summary of common petroleum distillate solvents and solvent blends and their associated HAP content. For any... 

The book has been edited by B.P. WHIM, with P.G. JOHNSON acting as co-editor for Part 2. The editors acknowledge with thanks the contributions of the various authors and the solvent suppliers who provided information on their products. They also wish to thank the staff of ICI CHLOR CHEMICALS for their help and advice—particularly Geoff Weemes and Graham Howe. 

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