Guaifenesin (Guaiacol glyceryl ether, 3-(2-Methoxyphenoxy)-1,2-propanediol, C10H14O4) is an expectorant that is found in cough medicines such as ActifedTM and RobitussinTM. U.S. 4,390,732 (to Degussa) describes a preparation of the active pharmaceutical ingredient (API) from guaiacol (2-methoxyphenol, C7H8O2) and glycidol (3-hydroxy propylene oxide, C3H6O2). When the reaction is catalyzed by NaOH, the reaction yield is 93.8%. The product is purified in a thin-film evaporator giving an overall plant yield of 87%.
a. Estimate the feed flow rates of glycine and guaiacol that would be needed to produce 100 kg/day of the API.
b. Estimate how much product is lost in the thin-film evaporator.
c. How would you recover the product lost in the evaporator?