Synthetic glycerine is back (but never really went away)!
Earlier this decade glycerine produced as a by-product of biodiesel manufactuee flooded the market, and the resulting crash in prices made it no longer viable to keep making Dow’s Optim synthetic version in North America. All other glycerine products are derived as by-products of soap and oleochemicals production.
As a result, in 2005 Dow decided to exit the market in North America, closing a production facility for synthetic glycerine in Freeport, Texas, that had been making more than 60,000 tonnes of the ingredient a year.
“What we didn’t realise at the time that out of that enormous tonnage was a section going to serve the pharmaceutical market,” said Eric Workman, commercial leader for Optim products at Dow in an interview.
“After we stopped, a lot of pharma customers came back to us asking us to reconsider, as no other glycerine was suitable because of impurities,” he added.
Optim is over 99.7 per cent pure, which is a real advantage in pharma and biotech applications, particularly in parenteral medicines such as insulin. In some cases non-synthetic glycerines have been shown to interfere with active pharmaceutical ingredients.
Moreover, Optim has a very long shelf-life of around two years, compared to roughly six to 12 months with other glycerines.
Manufacturers of by-product glycerines have been trying to remove their contaminants through various separation techniques to try to boost purity, but efforts have been largely unsuccessful, said Workman.
“Natural source-based products are prone to variability, for example from season to season.” And that means it is difficult to come up with a reliable protocol for cleaning them up, he added.
“Many of our customers switched to by-product glycerine, and felt that the differential in price justified the added investment in R&D, clinical trials and regulatory work,” according to Workman.
“What we’ve heard though is that in some cases the switch was made but didn’t work, because of the interactive effect of the contaminants in the by-product glycerine.”
German facility still running
All that aside, Dow continued to make synthetic glycerine, but only in Europe at a production site in Stade, Germany, which has the capacity to make around 30,000 tonnes of synthetic glycerine a year. It’s likely that for many customers the closure of the US site presented an opportunity to go and qualify the cheaper material.
“The supply from this site never stopped, but some customers are not aware of this and are still making suboptimal formulations of their drugs as they believe there is no alternative, ” said Workman. “We’re trying to make those customers aware that an alternative exists.”
To help generate that awareness, Dow has transferred marketing and sales responsibility for Optim from its SafeChem business unit to Dow Wolff Cellulosics, whose business is more closely aligned to the pharmaceutical excipients sector. Order processing and invoicing will continue to be managed by SafeChem.
