In this study, the temperature dependence of the heterogeneous uptake of acrylic acid on Arizona test dust （ATD） has been investigated within a temperature range of 255-315 K using a Knudsen cell reactor. Combined w...In this study, the temperature dependence of the heterogeneous uptake of acrylic acid on Arizona test dust （ATD） has been investigated within a temperature range of 255-315 K using a Knudsen cell reactor. Combined with diffuse reflectance infrared Fourier transform spectroscopy （DRIFTS） experiment, it was found that acrylic acid could adsorb on ATD via surface OH groups and convert to carboxylate on the particle surface. The kinetics study suggests that the initial true uptake coefficient （yt） of acrylic acid on ATD decreases from （4.02 ± 0.12） x 10-5 to （1.73 ± 0.05） x 10-5 with a temperature increase from 255 to 315 K. According to the temperature dependence of uptake coefficients, the enthalpy （AHobs） and entropy （ASobs） of uptake processes were determined to be -（9.60± 0.38） KJ/mol and -（121.55 ± 1.33） l.K/mol, respectively. The activation energy for desorption （Edes） was calculated to be （14.57 ± 0.60） KJ/mol. These results indicated that the heterogeneous uptake of acrylic acid on ATD surface was sensitive to temperature. The heterogeneous uptake on ATD could affect the concentration of acrylic acid in the atmosphere, especially at low temperature.展开更多
基金supported by the National Natural Science Foundation of China(Nos.41405118 and 91544227)the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(No.XDB05010400)+1 种基金the National Key Technology Support Plan Projects(No.2014BAC16B01)the Basic Scientific Research Progress of the Chinese Academy of Meteorological Sciences(No.2014Y007)
文摘In this study, the temperature dependence of the heterogeneous uptake of acrylic acid on Arizona test dust （ATD） has been investigated within a temperature range of 255-315 K using a Knudsen cell reactor. Combined with diffuse reflectance infrared Fourier transform spectroscopy （DRIFTS） experiment, it was found that acrylic acid could adsorb on ATD via surface OH groups and convert to carboxylate on the particle surface. The kinetics study suggests that the initial true uptake coefficient （yt） of acrylic acid on ATD decreases from （4.02 ± 0.12） x 10-5 to （1.73 ± 0.05） x 10-5 with a temperature increase from 255 to 315 K. According to the temperature dependence of uptake coefficients, the enthalpy （AHobs） and entropy （ASobs） of uptake processes were determined to be -（9.60± 0.38） KJ/mol and -（121.55 ± 1.33） l.K/mol, respectively. The activation energy for desorption （Edes） was calculated to be （14.57 ± 0.60） KJ/mol. These results indicated that the heterogeneous uptake of acrylic acid on ATD surface was sensitive to temperature. The heterogeneous uptake on ATD could affect the concentration of acrylic acid in the atmosphere, especially at low temperature.
