Pharmaceutical industry wastes

Wet synthesis reactions generally are batch types followed by extraction of the product. Extraction of the pharmaceutical product is often accomplished through 

Some antibiotics are produced in batch fermentation tanks in the presence of a particular fungus or bacterium. The culture frequently is filtered from the medium and marketed in cake or liquid form as an animal feed supplement. The antibiotic is extracted from the culmre medium through the use of solvents, activated carbon, etc. The antibiotic is then washed to remove residual impurities, concentrated, filtered, and packaged. 

The following industrial practices can significandy influence the wastewater characteristics  

Solvent recovery is practiced in both the synthesis and the fermentation products segment of the industry. Certain products may require a high-purity solvent in order to achieve the required extraction efficiency required. This increases the incentive for making the recovery process highly efficient. 

Some solvent streams which cannot be recovered economically, are incinerated. Incineration is also used to dispose of still bottoms from solvent recovery units. 

---

Howe, R.H.L. Handling wastes from the billion dollar pharmaceuticals Industry. Waste Engng. 1960, 31, 728-753. 

Bhushan, R. Martens, J. Thuku Thiongo, G. Direct thin layer chromatography enantioresolution of some basic DL-amino acids using a pharmaceutical industry waste as chiral impregnating reagent. J. Pharm. Biomed. Anal. 2000, 21, 1143-1147. 

In a catalytic asymmetric reaction, a small amount of an enantio-merically pure catalyst, either an enzyme or a synthetic, soluble transition metal complex, is used to produce large quantities of an optically active compound from a precursor that may be chiral or achiral. In recent years, synthetic chemists have developed numerous catalytic asymmetric reaction processes that transform prochiral substrates into chiral products with impressive margins of enantio-selectivity, feats that were once the exclusive domain of enzymes.56 These developments have had an enormous impact on academic and industrial organic synthesis. In the pharmaceutical industry, where there is a great emphasis on the production of enantiomeri-cally pure compounds, effective catalytic asymmetric reactions are particularly valuable because one molecule of an enantiomerically pure catalyst can, in principle, direct the stereoselective formation of millions of chiral product molecules. Such reactions are thus highly productive and economical, and, when applicable, they make the wasteful practice of racemate resolution obsolete. 

Spending effort on research to attempt to reduce what is really aleatory uncertainty is a waste of time. Accepting some unmanageable risks is simply part of the price of entry to the pharmaceutical industry. Once the limits of possible knowledge are accepted, research people can concentrate on discovering what is genuinely knowable. 

This serendipitous discovery marked the beginning of the synthetic dyestuffs industry, based on coal tar as its main raw material, which is, incidentally, a waste product from another industry, steel manufacture. The development of mauveine was followed by efficient syntheses of natural dyes such as alizarin in 1869 (Graebe and Liebermann, 1869), and indigo in 1878 (Bayer, 1878 Heumann, 1890). The synthetic production of these dyes marked the demise of the agricultural production of these materials and the advent of a science-based, predominantly German chemical industry. The present-day fine chemicals and specialties, e.g. pharmaceuticals, industries developed largely as spin-offs of this coal tar-based dyestuffs industry. 

Some aspects of synthetic chemistry have changed in response to environmental needs. For example, in the pharmaceutical industry the classical methods produce, on the average, about nine times as much disposable waste as desired product. This has led to the demand for procedures that have atom efficiency, in which all the atoms of the reacting compounds appear in the product. Thus (as discussed earlier) the demand for atom economy offers additional opportunities for creative invention of transformations. 

The pharmaceutical industry produces between 25 and 100 kg or more of waste for every kilogram of active pharmaceutical ingredient (API) manufactured.1 According to a leading practitioner of the industry, the potential waste coproduced with APIs is in the range of 500 million to 2 billion kg per year. Even at a nominal disposal cost of 1 per kg, the potential savings just in waste avoidance is significant faced to the pharmaceutical industry annual sales (almost 500 billion in 2003). 2... 

Pharmaceutical waste is one of the major complex and toxic industrial wastes [4]. As mentioned earlier, the pharmaceutical industry employs various processes and a wide variety of raw... 

Based on extensive experience in wastewater reduction and recovery experience at Bristol Labs (Syracuse, NY) and at the Upjohn Company (Kalamzoo, Michigan), the following practices have been recommended for waste control and recovery of byproducts in pharmaceutical industries [8,9,36,37] ... 

---