(Lectures, Sep 5-6) Topics on Producing Cellulose Nanomaterials, and Rapid and Low Temperature Wood Fractionation
time: 2017-09-04

Title 1: Producing Cellulose Nanomaterials
Time: 9:00a.m., Sep. 5th, 2017
Venue: Room 105, Shaw Engineering Building, Wushan Campus

Title 2:Rapid and Low Temperature ( ≤ 80 °C ) Wood Fractionation
Speaker: Prof.J.Y. Zhu (USDA Forest Service, Forest Products Laboratory, Madison, WI, USA)
Time: 9:00a.m., Sep. 6th, 2017
Venue: Room 306, State Key Laboratory of Pulp and Paper Engineering (newly built), Wushan Campus

Lignocellulose based nanomaterials such as cellulose nanocrystals (CNC) have attracted great interest recently due to renewability, biodegradability, and other unique mechanical and optical properties with a potential to produce a variety of products for a sustainable future. Economic and environmentally sustainable production, however, is the key to achieve these potentials.
In part I, I will present our recent study using dicarboxylic acids (DCAs) for sustainable and potentially economical production of highly thermal stable and functional (carboxylated) cellulose nanomaterials. DCA hydrolysis overcomes several disadvantages of existing technologies (mineral acid or enzymatic hydrolysis, oxidation such as TEMPO-mediated). DCAs can be easily and economically recovered through commercially proven crystallization process at ambient temperatures. DCA hydrolysis (DCAH) resulted in low CNC yield, but minimal cellulose loss or high solid yield. The remaining partially hydrolyzed fibers can be subsequently fibrillated into CNF to realize integrated production of CNC with CNF with tunable yield, properties, and morphologies.
In Part II, I will present a rapid and low temperature wood fractionation process for producing high value building blocks such as dissolving pulp fibers, sugar/biofuel, and lignin containing cellulose nanomaterials, lignin nanoparticles from wood directly. Approximately 90% of wood lignin can be dissolved at 80°C for 20 min. Equivalent delignification using alkaline wood pulping can be achieved only at 170°C for 2 h. This novel wood process fractionated wood into two fractions: (1) a primarily carbohydrate-rich water-insoluble solid fraction that can be used for sustainable production of high-value building blocks, such as dissolving pulp fibers and lignocellulosic nanomaterials, and/or sugars through subsequent enzymatic hydrolysis, and (2) a spent acid liquor stream containing mainly dissolved lignin that can be easily precipitated as lignin nanoparticles simply by diluting the spent acid liquor to below the minimal hydrotrope concentration.

Dr. J.Y. Zhu is a scientific team leader at the US Forest Service, Forest Products Laboratory, Madison, Wisconsin. He holds an Adjunct Appointment at the Dept. of Biological Systems Engineering, University of Wisconsin-Madison. He was the Inaugural Fulbright-Aalto University Distinguished Chair in Energy and Sustainable Use of Natural Resources (2015-2016 academic year), Helsinki, Finland. His research covers a broad area of wood and fiber utilization from wood pulping, fiber physics, bioenergy and biofuels, to cellulose nanomaterials that encompassed from laboratory studies to commercial scale demonstrations. Dr. Zhu’s achievements were honored with AIChE (American Institute of Chemical Engineers) Andrew Chase Award in 2016, TAPPI (Technical Association of the Pulp and Paper Industry) International R&D Technical Award and William Aiken Prize in 2014, and US Forest Service Deputy Chief for R&D Distinguished Science Award in 2013. Dr. Zhu is a Fellow of TAPPI, AIChE, and IAWS (International Academy of Wood Science).