Interfacial Phenomena on the Inorganic Scaling Prevention

Abstract

Superhydrophobic and lubricated slippery surfaces were tested under high salinity inorganic scaling medium and had their antifouling capacity assessed by optical and electron microscopy. The superhydrophobic surfaces were build up with hierarchically rough electropolymerized polyaniline onto stainless steel substrates and functionalized with low-polarizability thiols. Subsequently, these materials were lubricated with perfluorinated oil to obtain slippery surfaces. Regardless of the large amount of inorganic scale found onto superhydrophobic surfaces after the scaling test, the slippery ones showed to be very efficient as fouling preventers. From crystal quartz microbalance experiments, the wetting regime of the superhydrophobic surfaces was evaluated and shows that the Cassie–Baxter effect was not lost during the entire scaling test. The interfaces energies of the systems were assessed with contact angle experiments and showed that the scaling increases because the interfacial free energy is minimized. These results lead to a better understanding of how superhydrophobic surfaces could induce inorganic scaling instead of preventing it.

Advanced Antiscaling Interfacial Materials toward Highly Efficient Heat Energy Transfer

“…However, some converse results can also be reported in some other papers. For instance, Bertran and co‐workers built up the superhydrophobic surfaces with hierarchically rough electropolymerized polyaniline onto stainless steel substrates and functionalized with low polarizability thiols . From crystal quartz microbalance experiments, the wetting regime of the superhydrophobic surfaces was evaluated, showing that the Cassie‐Baxter effect still remained during the entire scaling test.…”

“…Furthermore, Sousa et al also prepared SLIPS by the infusion of silicon oil into electropolymerized and silanized porous polyaniline . In brief, hierarchically rough polyaniline were electropolymerized onto stainless steel substrates and further functionalized with low polarizability thiols (1 H , 1 H , 2 H , 2 H ‐perfluorodecanethiol, PFDT), thereby building up the superhydrophobic surfaces . In this place, aniline electropolymerization produced a coating with a textured morphology.…”

“…For instance, Bertran and co-workers built up the superhydrophobic surfaces with hierarchically rough electropolymerized polyaniline onto stainless steel substrates and functionalized with low polarizability thiols. [109] From crystal quartz microbalance experiments, the wetting regime of the superhydrophobic surfaces was evaluated, showing that the Cassie-Baxter effect still remained during the entire scaling test. The interfaces energies of the systems were assessed with CA experiments and showed that the scaling increases because the interfacial free energy is minimized.…”

“…[114] In brief, hierarchically rough polyaniline were electropolymerized onto stainless steel substrates and further functionalized with low polarizability thiols (1H, 1H, 2H, 2H-perfluorodecanethiol, PFDT), thereby building up the superhydrophobic surfaces. [109] In this place, aniline electropolymerization produced a coating with a textured morphology. PFDT modification was used to keep the perfluorinated polyether (Krytox) into the hollows of the rough surfaces and avoid its leakage during the scaling and cleaning stages.…”

Could petroleum work as lubricant oil on slippery lubricated surfaces to prevent inorganic scaling?

“…Works on literature show that superhydrophobic surfaces can prevent adhesion of contaminants (Barthlott and Neinhuis, 1997;Lejars et al, 2012;Bixler et al, 2014;Schmüser et al, 2016) but are not efficient when dealing with inorganic scaling process (Signorelli et al, 2019). On the other hand, slippery lubricated surfaces, which are surfaces covered by an oil attached into their rough structure, work well not only preventing adhesion onto them (Wong et al, 2011;Shillingford et al, 2014) but also avoiding heterogeneous nucleation over the surfaces, such as occurs in inorganic scaling (Grinthal and Aizenberg, 2014;Subramanyam et al, 2014;Charpentier et al, 2015;Sousa et al, 2017;Signorelli et al, 2019).…”