摘要
In order to evaluate the effects of La-involvement on biomass pyrolysis behaviors and properties of produced biochar, oak sawdust（OS） and corn straw（CS） were employed for thermogravimetric-differential thermogravimetric（TG-DTG） analysis and producing biochar with/without La-involvement. Results indicated the initial and final temperatures were shifted toward lower temperature as LaCl3 was involved in pyrolysis. Mass loss and average mass loss rate during pyrolysis decreased with La-involvement. The kinetics indicated that the first-order reaction kinetic model well matched the pyrolysis process. As La-involved OS and CS were employed, their apparent activation energies（Ea） were reduced, and their pyrolysis characteristic index（I） were higher comparing with the OS and CS without La-involvement. Based on the produced biochar, the yield and ash content were increased by La-involvement, and the O/C ratio and iodine sorption value（ISV） were also enhanced. Obviously, the loaded LaCl3 could facilitate pyrolysis process, and the produced biochar exhibited a great adsorption potential in aqueous solution. According to the results from FT-IR（Fourier transform infrared spectroscopy） analysis, La in pyrolysis functioned as accelerating lignin decomposition via condensing –OH, breaking aliphatic C–H and aromatic rings on lignin, cutting the links of C-O-C among the monomers in lignocellulose. LaCl3 was finally converted to La2O3 in biochar after pyrolysis.
In order to evaluate the effects of La-involvement on biomass pyrolysis behaviors and properties of produced biochar, oak sawdust（OS） and corn straw（CS） were employed for thermogravimetric-differential thermogravimetric（TG-DTG） analysis and producing biochar with/without La-involvement. Results indicated the initial and final temperatures were shifted toward lower temperature as LaCl3 was involved in pyrolysis. Mass loss and average mass loss rate during pyrolysis decreased with La-involvement. The kinetics indicated that the first-order reaction kinetic model well matched the pyrolysis process. As La-involved OS and CS were employed, their apparent activation energies（Ea） were reduced, and their pyrolysis characteristic index（I） were higher comparing with the OS and CS without La-involvement. Based on the produced biochar, the yield and ash content were increased by La-involvement, and the O/C ratio and iodine sorption value（ISV） were also enhanced. Obviously, the loaded LaCl3 could facilitate pyrolysis process, and the produced biochar exhibited a great adsorption potential in aqueous solution. According to the results from FT-IR（Fourier transform infrared spectroscopy） analysis, La in pyrolysis functioned as accelerating lignin decomposition via condensing –OH, breaking aliphatic C–H and aromatic rings on lignin, cutting the links of C-O-C among the monomers in lignocellulose. LaCl3 was finally converted to La2O3 in biochar after pyrolysis.
基金
Project supported by Key R&D Projects of Sichuan Province from the Science&Technology Department of Sichuan Province(2017SZ0028)
Program for Changjiang Scholars and Innovative Research Team in University from the Ministry and Education of China(IRT13083)
