Wednesday, January 15, 2014

Process Wednesday: the smelly chemical operators of Widnes

I recently purchased a copy of Derek Walker's "The Management of Chemical Process Development in the Pharmaceutical Industry." Lots of good stuff in there (including some really wild speculation in the back about the economy and such). But, in the middle, lots of good lessons on process development and fun anecdotes about life in pharmaceutical companies in the 1980s and 1990s. Here's a good one about sourcing a new fermentation starting material for a process to generate penicillin G:
Despite the turbulence encountered in all process improvement and process development work, there were the occasional triumphs of applied common sense. One of considerable social as well as economic consequence, occurring in the manufacture of penicillin G, resulted from the Ulverston process improvement attending the switch from buying solid phenylacetic acid to purchasing an aqueous solution containing 50% sodium phenylacetate. In using the solid, our factory workers weighted the required amount of phenylacetic acid and then dissolved it in aqueous sodium hydroxide to produce the aqueous solution used for feeding the penicillin fermenters. 
The handling of solid phenylacetic acid had created problems for many years, both for the Ulverston factor and for our vendor, Albright and Wilson (A&W). Solid phenylacetic acid introuced an obnoxious, pervasive, sweaty aroma to the penicillin G buildings and the workers' clothes and homes in Ulverston. The odors in Ulverston and surrounding communities were, however, almost trivial besides those encountered by the A&W workers. 
Keith Partridge, Sales and Marketing Manager for A & W during my time at Ulverston (1966-1975), recounted the privations of process operators manufacturing phenylacetic acid in A&W's Ann Street works in Widnes. They were paid a "social bonus" for working in the plant. Keith said you could walk down the street where they lived and identify their houses by the smell!! No one would sit in their seats at the local public house -- even their beer glasses were segregated!! The ultimate indignity occurred, when Vernons, the football pool company, asked one worker not to send in his weekly pool coupon because of odor complaints from the clerks who processed it!!!  
The common sense use of the 50% aqueous solution of phenylacetic acid virtually eliminated the handling of solid material, though it took some time and a few plant trials to convince the production managers that there was nothing else int he A&W aqueous solution which might have an adverse effect on the penicillin G titer.  
I definitely sympathize with the production managers here: "Yes, this stuff stinks, but it works, it keeps our quotas up, and we're still getting paid. We go to this liquid stuff, it doesn't stink as much, but if we screw up, we blow two or three batches and we're behind for the year." It must have felt like a real risk in making the switch, even if the chemistry made a lot of sense.

That said, you wouldn't see me volunteering to take shifts in a phenylacetic acid plant. 


  1. the "sweaty" does not cover it. The diluted smell of phenylacetic acid (that does stick to clothes like nothing else, and permeates the workspace like a mold) is actually similar to smell of dried urine, just like old ladies with a little leakage problem. Then there is the foul overtone of artificial honey flavoring...

    We had a zombie-like technician at one of the previous companies. One of the many things he did, was dropping a half-kilo-sized bottle of phenacetyl chloride on the floor and smearing the puddle with a rag, (probably so that he can cover as large area as possible). The acrid stench of acylchloride disspated next day, but the phenylacetic acid nauseating sweetish urine-like background odor clenched to that lab and everyone who worked there even a year later...

  2. Milkshake is absolutely right: "sweaty" does not cover it.
    Long time ago I worked at the hydrolysis of phenylacetonitrile to phenylacetamide. It always ended up with some percent of byproduct phenylacetic acid. My lab desk kept on smelling for a couple of years after the project was over.....

  3. How do you get rid of the smell?