Monday, May 4, 2009
9-67

Foaming Tannin from a Cellulose-Tannin Solution

Robert D. Tanner and Joseph Mikhail. Chemical Engineering, Vanderbilt University, VU Station B 351604, Nashville, TN 37235

 Foam Fractionation is an inexpensive chemical process in which molecules are separated from a liquid solution by using a gas, such as air, to carry them out of solution and into the collected foam. When that foam is collapsed into a liquid it is called the foamate. Foam fractionation of tea solutions and grape tannin are analyzed in this study, with or without the presence of ethyl cellulose, to see if separation of tannins or tannin-like materials from cellulose can be achieved. It was observed, that a cold (20°C) tea solution produced more foam and at a faster rate than a hot (95°C) tea solution.  The foamate and different layers of tea were analyzed for color (mean of the optimal density vs. spectrophotometer wavelength distribution).  If tannin can be removed from a tannin-cellulose system by foaming, then perhaps lignin could also be removed by foaming from lignocellulosic solutions.  A low cost tannin/lignin removal step could make the  generation of sugars from a lignocellulose (and on to ethanol) biofuel production process more economical.