Liquid–liquid equilibrium (LLE) compositions were measured for the pseudoternary system lignin–acetic acid–water at 70 and 95 °C, conditions of interest for the Aqueous Lignin Purification using Hot Acids (ALPHA) process for the purification and fractionation of lignin. Other regions of phase behavior, including a narrow region of LLE at high acetic acid (AcOH) concentrations, as well as solid–liquid (SL) and solid–liquid–liquid (SLL) equilibria, were also identified so that the global phase behavior could be mapped out. For both temperatures, tie-lines encompassing the entire region of “ALPHA” LLE were measured, from near the liquid–liquid critical point in the AcOH-rich region to the solid–liquid–liquid (SLL) phase boundary in the water-rich region. This LLE region exhibited several interesting characteristics. Surprisingly, there was essentially no difference between the solvent compositions in the solvent-rich vs. the lignin (polymer)-rich phase, indicating that the solvent mixture is exhibiting the properties of a single liquid solvent with respect to the lignin polymer. Furthermore, a strong maximum was measured on the lignin-rich side of the binodal curve, which can occur when a solvent mixture consists of strongly associating fluids. The average molecular weight of the lignin in the lignin-rich phase was found to be an order-of-magnitude higher than in the solvent-rich phase. Acid-catalyzed lignin condensation reactions were found to occur at the highest AcOH concentrations and temperatures in the lignin-rich phase, but there was no impact on the measured phase compositions.
Fluid Phase Equilibria – Elsevier
Published: Apr 15, 2018
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera