*3.10. High Added-Value Applications for Lignin*

As an overview, the lignin obtained from the formosolv fractionation of Paulownia wood results in a high decrease in labile ether bonds, with an increase in its polydispersity, and also reflecting recondensation phenomena. However, some works reflected the chance of employing this kind of lignin for several purposes. Some applications, via a further upgrading of the lignin, may be its use as an adsorbent for heavy metal such as Pd or Cr [47] in the form of lignin nanoparticles, as well as for the manufacture of polymeric resins, polyurethanes and polyesters [48,49]. In addition, this lignin may also be used as a flocculant, cement additive, etc. On the other hand, if the lignin is employed for consequent catalytic depolymerization, it can be subjected to pyrolysis or other kinds of treatment for the production of aromatic monomers, or for the obtainment of biofuels [47]. All of these may be attractive applications for the exploitation of lignin.
