Companies have put biofuels on the back burner to aim for higher margin chemicals, as Emma Davies finds out Tom Welton gives the wooden desk in his office a sharp rap with his knuckles. ‘That’s the sound of lignin,’ he says, grinning. ‘Have you seen its structure? It’s beautiful, full of aromatics, lovely compounds that make you think: I could make something useful from this.’Welton, who is head of chemistry at Imperial College London, UK, views lignin – the ‘really hard stuff’ that protects plants from biological attack – as a valuable source of renewable speciality chemicals. His group has...