Studies of Thermal Transformations of Humic and Fulvic Acids in Soils I. Infrared Spectroscopy and Temperature-Programmed Pyrolysis Mass Spectrometry
Titel:
Studies of Thermal Transformations of Humic and Fulvic Acids in Soils I. Infrared Spectroscopy and Temperature-Programmed Pyrolysis Mass Spectrometry
Auteur:
Zuyi, Tao Shifang, Liu Jianjun, Zhai Fenling, Sheng
Verschenen in:
Chemistry & ecology
Paginering:
Jaargang 13 (1997) nr. 4 pagina's 237-248
Jaar:
1997-07-01
Inhoud:
Temperature-programmed pyrolysis mass spectrometry and Fourier-transform infrared spectroscopy have been used to monitor structural changes of humic and fulvic acids isolated from soils in China, in the temperature range of 25-550°C. in this work, we found that decarboxylation is obvious as the main reaction with dehydration reaction from 150°C to 400°C, the anhydride can be identified from FT-IR spectra at temperature range from 200°C to 400°C; there are evident changes of the aromatic nucleus of humic and fulvic acids above 400°C, even remaining up to 550°C. Besides, some changes of adsorption water can be distinguished before 200°C, and the mass signal of sulphur dioxide was detected.