| Title: | Dynamic Evolution and Covariant Response Mechanism of Volatile Organic Compounds and Residual Functional Groups during the Online Pyrolysis of Coal and Biomass Fuels |
| Author(s): | Song F; Li T; Wu F; Leung KMY; Bai Y; Zhao X; |
| Address: | "State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China. School of Environment, Tsinghua University, Beijing 100084, China. State Key Laboratory of Marine Pollution, and Department of Chemistry, City University of Hong Kong, Kowloon, Hong Kong 999077, China" |
| ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
| Abstract: | "Volatile organic compound (VOC) emissions from pyrolysis of widely used biomass are expected to increase significantly under the carbon neutrality target. However, the dynamic emissions and evolution mechanism of biomass-VOCs remain unclear, hindered by complex reactions and offline measurements. Here, we propose a novel covariant evolution mechanism to interpret the emission heterogeneities, sequential temperature responses, and evolved correlations of both VOCs and residual functional groups (RFGs) during corn straw (CS), wood pellet (WP), and semibituminous coal (SBC) pyrolysis. An innovative combination of online thermogravimetric-Fourier transform infrared-gas chromatography/mass spectrometry and two dimensional-correlation spectroscopy was applied. The relative percentages of CS/WP-VOCs were higher than those of SBC-VOCs, and most VOCs tended to have relatively small carbon skeletons as the average carbon oxidation state increased. With the temperature increased from low to high during CS/WP pyrolysis, the primary sequential response of VOCs (acids --> phenols/esters --> alcohols/ethers/aldehydes/ketones --> hydrocarbons/aromatics) corresponded to the RFG response (hydroxyl groups --> -CH(3)/-CH(2)-/-CH groups --> aliphatic ethers and conjugated ketones). Compared with the relative regularity for CS/WP responses, the gas-solid products from SBC pyrolysis exhibited complex temperature-dependent responses and high oxidation-induced variability. These insights provide favorable strategies for the online monitoring system to facilitate priority removal of coal and biomass fuels-VOCs" |
| Keywords: | Biomass Carbon *Coal Ethers/analysis Gas Chromatography-Mass Spectrometry Ketones Pyrolysis *Volatile Organic Compounds Zea mays carbon oxidation state coal and biomass fuels pollution control reaction heterogeneity volatility distribution; |
| Notes: | "MedlineSong, Fanhao Li, Tingting Wu, Fengchang Leung, Kenneth Mei Yee Bai, Yingchen Zhao, Xiaoli eng Research Support, Non-U.S. Gov't 2022/04/09 Environ Sci Technol. 2022 May 3; 56(9):5409-5420. doi: 10.1021/acs.est.1c08400. Epub 2022 Apr 8" |
