Rapid and near-complete dissolution of wood lignin at ≤80°C by a recyclable acid hydrotrope

Research output: Contribution to journalArticleScientificpeer-review


  • Liheng Chen
  • Jinze Dou

  • Qianli Ma
  • Ning Li
  • Ruchun Wu
  • Huiyang Bian
  • Daniel J. Yelle
  • Tapani Vuorinen

  • Shiyu Fu
  • Xuejun Pan
  • Junyong (J. Y. ) Zhu

Research units

  • Jinan University
  • United States Department of Agriculture
  • South China University of Technology
  • University of Wisconsin-Madison
  • Guanxi University for Nationalities
  • Nanjing Forestry University


We report the discovery of the hydrotropic properties of a recyclable aromatic acid, p-toluenesulfonic acid (p-TsOH), for potentially low-cost and efficient fractionation of wood through rapid and near-complete dissolution of lignin. Approximately 90% of poplar wood (NE222) lignin can be dissolved at 80 degrees C in 20 min. Equivalent delignification using known hydrotropes, such as aromatic salts, can be achieved only at 150 degrees C or higher for more than 10 hours or at 150 degrees C for 2 hours with alkaline pulping. p-TsOH fractionated wood into two fractions: (i) a primarily cellulose-rich water-insoluble solid fraction that can be used for the production of high-value building blocks, such as dissolving pulp fibers, lignocellulosic nanomaterials, and/or sugars through subsequent enzymatic hydrolysis; and (ii) a spent acid liquor stream containing mainly dissolved lignin that can be easily precipitated as lignin nanoparticles by diluting the spent acid liquor to below the minimal hydrotrope concentration. Our nuclear magnetic resonance analyses of the dissolved lignin revealed that p-TsOH can depolymerize lignin via ether bond cleavage and can separate carbohydrate-free lignin from the wood. p-TsOH has a relatively low water solubility, which can facilitate efficient recovery using commercially proven crystallization technology by cooling the concentrated spent acid solution to ambient temperatures to achieve environmental sustainability through recycling of p-TsOH.


Original languageEnglish
Article number1701735
Number of pages11
JournalScience Advances
Issue number9
Publication statusPublished - Sep 2017
MoE publication typeA1 Journal article-refereed

    Research areas


Download statistics

No data available

ID: 16977172