The Use of Pyrolysis GC/MS as a Single Analytical Tool for the Structural Characterization of NOM and the Identification of DBP Precursor Sites
使用热解GC/MS作为单一分析工具 对NOM进行结构表征 并识别DBP前体位置
The objective of our work was to compare the structural information that can provide flash pyrolysis GC/MS on natural organic matter (NOM) and its structural characteristics established using other relevant methods such as 13 C-NMR, elemental analysis and total dissolved amino acid and carbohydrate content. This work was conducted on 65 hydrophobic and hydrophilic NOM fractions isolated from raw and treated waters using XAD resin isolation based protocols. The nature and relative abundance of structural units in the NOM molecules determined by solid state 13 C-NMR were in good agreement with the biopolymer distribution established based on the relative abundance of some specific peaks of the pyrochromatograms. Elemental analysis and total dissolved amino acids and carbohydrate contents support this finding. The results of the reactions with chlorine showed that the hydrophilic fractions of NOM (lower aromaticity but more enriched in proteins and aminosugars) produced significantly higher yields of haloacetic acids (HAAs) compared to trihalomethanes (THMs) that were counter to the results for hydrophobic NOM. A good relationship could be established between the relative abundance of proteins in the lower molecular weight hydrophilic NOM fractions and the production of haloacetonitriles. Includes 24 references, table, figures.