کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1203223 1493584 2014 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Recent advances in thermal desorption-gas chromatography-mass spectrometery method to eliminate the matrix effect between air and water samples: Application to the accurate determination of Henry's law constant
ترجمه فارسی عنوان
پیشرفت های اخیر در روش اسپکترومتری کروماتوگرافی جیوه گرمایی برای حذف اثر ماتریکس بین نمونه های هوا و آب: کاربرد برای تعیین دقیق قانون هنری
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
چکیده انگلیسی


• Despite the usefulness, the availability of the Henry's constant is limited to a number of compounds.
• Large uncertainties exist in the pre-existing database of Henry's constant for certain chemicals.
• The reliability of the experimental approaches for HLC estimations is yet insufficiently validated.
• Here we provide an experimental approach to determine the Henry's constant with the least bias.

Accurate values for the Henry's law constants are essential to describe the environmental dynamics of a solute, but substantial errors are recognized in many reported data due to practical difficulties in measuring solubility and/or vapor pressure. Despite such awareness, validation of experimental approaches has scarcely been made. An experimental approach based on thermal desorption-gas chromatography-mass spectrometery (TD-GC-MS) method was developed to concurrently allow the accurate determination of target compounds from the headspace and aqueous samples in closed equilibrated system. The analysis of six aromatics and eight non-aromatic oxygenates was then carried out in a static headspace mode. An estimation of the potential bias and mass balance (i.e., sum of mass measured individually from gas and liquid phases vs. the mass initially added to the system) demonstrates compound-specific phase dependency so that the best results are obtained by aqueous (less soluble aromatics) and headspace analysis (more soluble non-aromatics). Accordingly, we were able to point to the possible sources of biases in previous studies and provide the best estimates for the Henry's constants (M atm−1): benzene (0.17), toluene (0.15), p-xylene (0.13), m-xylene (0.13), o-xylene (0.19), styrene (0.27); propionaldehyde (9.26), butyraldehyde (6.19), isovaleraldehyde (2.14), n-valeraldehyde (3.98), methyl ethyl ketone (10.5), methyl isobutyl ketone (3.93), n-butyl acetate (2.41), and isobutyl alcohol (22.2).

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Chromatography A - Volume 1342, 16 May 2014, Pages 78–85
نویسندگان
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