Wettability determined by capillary rise with pressure increase and hydrostatic effects
Bigui Wei1, Qing Chang, Caiyun Yan
1Engineering Research Center for Cold and Arid Regions Water Resource Comprehensive Utilization of Ministry of Education, School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, Gansu 730070, China.
Journal of Colloid and Interface Science
|April 10, 2012
Summary
This study introduces a new method to measure particle wettability using capillary rise, independent of particle size. The findings enable accurate contact angle determination for small particles with different liquids.
Area of Science:
- Surface Science
- Materials Science
- Physical Chemistry
Background:
- Capillary rise is crucial for determining contact angles and wettability of small particles.
- The Classical Washburn equation relies on an equivalent hydraulic radius (r(d)) assumed to be constant.
- This assumption is challenged as r(d) can vary with different liquid types.
Purpose of the Study:
- To develop a novel method for measuring small particle contact angles and wettability.
- To overcome the limitations of the Washburn equation regarding the hydraulic radius.
- To enable accurate wettability measurements independent of the particle-specific radius r(d).
Main Methods:
- Theoretical derivation of a new equation based on the Washburn equation.
- Incorporation of pressure increment and hydrostatic effects into the model.
- Experimental validation of the proposed method for contact angle measurement.
Main Results:
- The new equation accurately measures contact angles independently of the equivalent hydraulic radius r(d).
- Demonstrated validity of the proposed method through experimental results.
- The approach allows for accurate wettability assessment of small particles across different liquid types.
Conclusions:
- The developed method provides a more accurate way to measure the wettability of small particles.
- This advancement overcomes the limitations of the Classical Washburn equation.
- Accurate contact angle and wettability determination is now possible without relying on a constant r(d).
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