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Laboratory equipment costs just a miniscule fraction of that of process equipment. For that reason scientists can perform a reaction which requires strong aqueous alkali in a glass round bottomed flask even though one knows that at the end of the reaction the flask will be opaque and etched by the dissolution of a portion of the glass itself. On the other hand precautions must be taken that a large scale reactor, which is expected to have a long useful life should not be partially dissolved or pitted or weakened by the reactor contents. The process development chemist must never put the reactor at risk. Consideration should be paid early on that reaction conditions are not incompatible with the materials of construction. Engineers are particularly knowledgable in this area and can provide an early warning that particular conditions must be examined. This is normally done in the laboratory by placing weighted tiles of reactor surface material into the laboratory reactor throughout the process step of concern and at the end these tiles are fished out and carefully reweighted. Any experimentally significant difference between the before and after weights is suggestive that the reaction conditions are eroding the reactor surface material. At the same time the experiment will detect any unexpected affect of the reactor material on the course of the process reaction.

Loss of the surface of the reactor can be caused by abrasion where the surface is simply rubbed off and probably remains as fine insoluble particles in side the reactor. Very little can be done about this except to get away from the abrasive reagent. some times this problem can be solved by packing the abrasive agent tightly into a special column and rapidly circulating the solution reaction mixture through the column past the abrasive agent.

Loss of the reactor surface may simple be caused by excessive pHs and this can be controlled by an adjustment in the reactor material itself.

Another cause is the use of or the creation of a very strong chelating agent which simply rips metal ions out of the reactor surface. In such a situation I was able to overcome the corrosion simply by adding a stoichiometric quantity of an inorganic iron salt into the reactor with the rest of the reagents. As the chelator formed it complexed the iron cations and left the reactor alone.

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• Pamoates or Embonates: crystalline Pharmaceutical Salts or Derivatives for Isolation and Purification
• Symmetrical Bis-N,N-(3-nitrophenyl)urea: A Super Co-crystal Former that might have applications in Product Purification.
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• Inverted Filtration: A chemical synthesis laboratory technique particularly helpful at 5-10 litre scales.
• Recovering More Product by Crystallization in Organic Synthesis:Trituration with a Modified Water Phase as a Potential Chemical Process Development Method
• Kilomentor moves the discussion from Steam Distillation to other Co-distillations

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