Measuring water repellency of individual particles: The new “micro-Wilhelmy Plate Method” and its applicability to soil

Abstract

Highlights• We introduce a new technique that allows measuring water repellency of individual particles • Two variants of the method each provide relatively simple and quick wettability assessments • It showed naturally wettable bulk soils contained water repellent particles and vice versa

Pre-evaluation of contaminated soil for oil field reactivation in Moloacan, Veracruz, Mexico

“…However The trends in Figure IV show that as the hydrocarbon concentration increases, the sand content also increases and the clay content decreases (in range of 8,800-18,000 mg kg −1 ), which coincides with the literature (Vogel et al, 2020). In addition, these trends show that these changes depend on the concentration, since in samples with concentrations below ∼5000 mg kg −1 (polygon a, close to the MLP for agricultural use) the textural classification similar to the control is preserved and, from these concentrations and in those below ∼25,000 mg kg −1 , the classification is transformed to coarser textures (polygon b) and, for samples with concentrations higher than this last value, clays are ∼5% and sands are greater than ∼90% (polygon c).…”

Robust and durable liquid-repellent surfaces

“…Recently, it was shown that the Wilhelmy balance technique could also be used for the CA measurement of irregular shaped samples with a variable perimeter. 136,137 For example, Park et al proposed to determine the perimeter of the sample as a function of the immersion depth by profile plot obtained from the optical image, and then measured the ACA and RCA via the Wilhelmy balance method, which was verified with triangular and irregular PTFE sheets in water. 136 However, the precise estimation of P cl in eqn ( 27) and ( 28) is always difficult, especially for those porous or textured surfaces, the contact line is significantly different from the geometric perimeter, which can be a large source of error.…”

Evaluation of Viscosity Dependence of the Critical Meniscus Height with Optical Fiber Sensors

“…One of the most widely used conventional techniques to measure the surface properties (like surface tension and contact angle) of a liquid is the Wilhelmy method [9][10][11][12][13][14][15][16][17][18][19]. This method is based on measuring the contact angle of a liquid with respect to a solid when the surface tension of the liquid is known.…”