全部 标题 作者
关键词 摘要

OALib Journal期刊
ISSN: 2333-9721
费用:99美元

查看量下载量

相关文章

更多...
环境化学  2015 

降水中有机酸对自由酸度贡献量的热力学平衡计算法

Keywords: 酸雨,有机酸,自由酸度,热力学

Full-Text   Cite this paper   Add to My Lib

Abstract:

根据平衡热力学理论,考虑温度(T)、压强(P)和离子强度(I)等因素的影响,提出了一种新的有机酸对降水自由酸度贡献的计算方法(热力学平衡计算法),评价了上述三个因素的变化对有机酸酸度贡献量的影响.研究表明(1)只有当降水pH≤5时,才能有效计算有机酸对降水自由酸度的贡献,这是有机酸对酸度产生贡献的前提;(2)pH值对有机酸酸度贡献有着直接而主要的影响;其次是T,它对甲酸和乙酸酸度贡献的相对偏差可分别高达9.4%和32.0%;(3)当P变化不大(0.870×105—1.013×105Pa)时,其对有机酸酸度贡献的影响可以忽略,而I对有机酸酸度贡献几乎无影响,即忽略降水中离子之间的相互作用;(4)对比显示,已有方法计算所得的有机酸酸度贡献结果仅仅是本方法在298.15K和1.013×105Pa且忽略碱性离子中和情况(X%=0)的条件下所计算出结果的一种特例.

References

[1]  Chapman E G, Sklarew D S, Fllickinger J S, Organic Acid in Springtime Wisconsin Precipitation Samples.Atmospheric Environment, 1986, 20(9):1717-1725
[2]  傅献彩, 沈文霞, 姚天扬, 物理化学(第四版)上册.北京:高等教育出版社, 1990, 379-406
[3]  Partanen J I, Calculation of Stoichiometric Dissociation Constants of Formic, Acetic, Glycolic and Lactic Acids in Dilute Aqueous Potassium, Sodium or Lithium Chloride Solutions at 298.15K.Acta Chemica Scandinavica, 1998, 52(8):985-994
[4]  Shock E L, Organic Acids in Hydrothermal Solution:Standard Molal Thermodynamic Properties of Carboxylic Acids and Estimates of Dissociation Constants at High Temperatures and Pressures.American Journal of Science, 1995, 295:496-580
[5]  Moschonas N, Glavas S, Weak Organic Acidity in a Wet-only Precipitation Study at a Mediterranean Coastal Site, Patras, Greece.Atmospheric Research, 2002, 63(1-2):147-157
[6]  Keene W C, Galloway J N, Organic Acidity in Precipitation of North America.Atmospheric Environment, 1984, 18(11):2491-2497
[7]  Yu S, Gao C, Cheng Z et al., An Analysis of Chemical Composition of Different Rain Types in 'Minnan Golden Triangle' Region in the Southeastern Coast of China.Atmospheric Research, 1998, 47-48:245-269
[8]  Keene W C, Galloway J N, Holden J D, Measurement of Weak Organic Acidity in Precipitation from Remote Areas of the World.Journal of Geophysical Research, 1983, 88(C9):5122-5130
[9]  Tanner P A, Law P T, Organic Acids in the Atmosphere and Bulk Deposition of Hong Kong.Water, Air and Soil Pollution, 2003, 142:279-297
[10]  Fornaro A, Gutz I G R, Wet Deposition and Related Atmospheric Chemistry in the So Paulo Metropolis, Brazil:Part 2-Contribution of Formic and Acetic Acids.Atmospheric Environment, 2003, 37(1):117-128
[11]  俞绍才, 蔡小平, 厦门海洋性酸雨中有机弱酸的研究.上海环境科学, 1992, 11(12):30-32
[12]  Possanzini M, Buttini P, Dipalo V, Characterization of a Rural Area in Terms of Dry and Wet Deposition.Science of Total Environment, 1988, 74:111-120
[13]  Shock E L, Helegson H C, Calculation of the Thermodynamic and Transport Properties at High Pressures and Temperatures:Standard Partial Molal Properties of Organic Species.Geochimica et Cosmochimica Acta, 1990, 54:915-945
[14]  Archer D G, Wang P, The Dielectric Constant of Water and Debye-Hückel Limiting Law Slopes.Journal of Physical and Chemical Reference Data, 1990, 19(2):371-409
[15]  Lin C L, Lee L S, A Two-Ionic-Parameter Approach for Ion Activity Coefficients of Aqueous Electrolyte Solutions.Fluid Phase Equilibria, 2003, 205:69-88
[16]  Wagner W, Pruβ A, The IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use.Journal of Physical and Chemical Reference Data, 2002, 31(2):387-535
[17]  Partanen J I, Calculation of Stoichiometric Dissociation Constants of Monoprotic Carboxylic Acids in Dilute Aqueous Sodium or Potassium Chloride Solutions and p[m(H+)] Values for Acetate and Formate Buffers at 25℃.Talanta, 2000, 52:863-871

Full-Text

Contact Us

service@oalib.com

QQ:3279437679

WhatsApp +8615387084133