Polyethyleneimine-functional cellulose aerogels and wood-based templates for CO2 capture

CO2回収のためのポリエチレンイミン機能化セルロースエアロゲルと木質鋳型

2020-09-24

2020-09-24

Polyethyleneimine (PEI) functionalized mesoporous sorbent have been widely studied for chemisorb CO2. However, those porous materials of aerogels show high cost and complicated process to restrict the application in industry. In this work, the cellulose aerogel with low density and high specific surface area was prepared by the non-solvent impacted thermally induced phase separation (NITIPS) method and hydrolysis process. After PEI impregnation process, the PEI-impregnated cellulose (PIC) aerogel showed large shrinkage due to the low mechanical strength and large hygroscopicity. Hence, a novel polyethyleneimine-crosslinked cellulose (PCC) aerogel sorbent was prepared through the crosslinking reaction. The obtained porous PCC aerogel showed 3D network structure with irregularly shaped microscale and nanoscale pores and large specific surface area. The CO2 adsorption capacity of PCC-1 aerogel reached 2.31 mmol/g at 25 °C under pure dry CO2 atmosphere based on the chemical and physical absorption. The PCC aerogel showed excellent CO2 adsorption-desorption recyclability, retaining 93% of the initial value after 10 adsorption-desorption cycle tests. However, the CO2 selective and mechanical properties of materials still face huge challenges to meet the practical requirement. Therefore, a high strength delignified wood was developed to be a matrix to load PEI for CO2/N2 selective adsoroption. After lignin removal, the delignified wood showed micro- and meso-porous structure with high specific surface area (44.3 m2/g) determined with physical CO2 adsorption. With the increasing the PEI loading content, the PEI-delignified wood composite with 49 wt% of PEI (P49) showed super-high CO2/N2 ideal selectivity (S = 114), high CO2 adsorption capacity (2.96 mmol/g) and excellent CO2 cyclic performance at 120 °C. Pseudo-second order model accurately predicted the CO2 adsorption behaviors of P49 at different temperature based on chemical adsorption. More importantly, the Young`s modulus of P49 reaches to 756 MPa, over 10 times higher than that of cellulose porous materials reported in literature. The developed PEI-delignified wood would play an important role in the combustion industry as a potential CO2 adsorption sorbent.

博士(工学)

京都工芸繊維大学

14303甲第976号

http://hdl.handle.net/10212/2604

eng

ETD

Thesis or Dissertation

Thesis