Producing High Yields of Paracetamol from Biomass-Derived P-Hydroxybenzoic Acid and P-Hydroxybenzamide
Introduced in the early 1900s, paracetamol (acetaminophen) is an active ingredient in many widely sold over-the-counter medicines such as Tylenol and today is the most commonly used medication for pain and fever in the U.S. It has traditionally been made from derivatives of coal tar or petroleum.
UW-Madison researchers previously developed a two-step process to synthesize paracetamol from p-hydroxybenzamide, a compound easily isolated from lignin sourced from biomass species including poplar, aspen, willow and palm. Now, they have developed improved methods of using chemicals from lignin as the starting material to produce paracetamol with increased yields and scalability.
The methods start with isolation of either p-hydroxybenzoic acid or a mixture of p-hydroxybenzoic acid and p-hydroxybenzamide from biomass. One version requires the conversion of p-hydroxybenzoic acid to p-hydroxybenzamide, then to p-aminophenol and finally to paracetamol. The researchers also developed a flow reaction that recycles unreacted p-hydroxybenzamide from earlier steps to feed into the amide-to-amine conversion step. Optimizing these processes has resulted in yields greater than 90%.
- Cost-effective
- High yields (greater than 90%)
- Environmentally sustainable – process uses renewable biomass, is primarily water based and relies on green solvents
- Continuous, making it ideal for industrial applications
- Offers a greener path to producing paracetamol and other chemicals
- Could provide new revenue streams to make cellulosic biofuels cost competitive with fossil fuels
For current licensing status, please contact Jennifer Gottwald at jennifer@warf.org or 608-960-9854