Surface-washing agents effectiveness

Effectiveness and Toxicity of Some Surface-Washing Agents... 

While chemical agents other than beach cleaners or surface-washing agents are sometimes suggested for shoreline cleanup, they should not be used as they are not effective and can cause additional problems. Dispersants generally increase the penetration of the oil, which makes them unsuitable for use on shorelines. Solidifiers or recovery agents do not assist with oil recovery. 

Effectiveness. Field Trials. Several tests of the effectiveness of surface-washing agents have been conducted at actual spills. The results of some of these tests are listed in Table 12 [119, 122, 126-135], Effectiveness was not quantified in any of these field tests, however, in every case, except where dispersants were used in earlier years, the tests were declared to be successful. The earlier dispersant trials showed variable effectiveness and, where penetration was measured, showed that dispersants promoted penetration of the oU into the sub-sediments [135],... 

Protection from the effect of alkaline solutions (e.g. washing agents) can be provided for glass surface by adsorption of inhibitors introduced in the solution (salts of Be, Sn, Zn, Al, etc.). 

Emulsification is the most important act of the washing process. To prevent secondary soil deposition, formation of a coalescence-stable low-concentration emulsion is needed. As it is shown above (see section 6.4), the formation of such an emulsion is possible under real conditions considering the surfactant concentration in the washing solution and hydrodynamic conditions of the soil deposition process. As far as solid soils are concerned, the process of dispersion of particles is important here. To prevent their re-deposition on the surface washed, water-soluble polymers are used, e.g. carboxymethyl cellulose. Effective dispersion agents are also inorganic salts, e.g. alkali metal silicates. 

Divalent cations must be removed from the wash water because of the negative role played by these cations in precipitating various insoluble salts, including anionic surfactant salts this boils down to consuming these surfactants while canceling their effects as surface-active agents. 

The effect of the treatment of the surface of the first latex layer with different materials on the degree of autohesion was studied. For this purpose, we washed the surface of the substrate with a small amount of one of the following materials potassium oleate solution (ionic surface-active agent) or alkylarylpolyether alcohol solution (non-ionic surface-active agent). 

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