Bioinspired Solar‐Heated Carbon Absorbent for Efficient Cleanup of Highly Viscous Crude Oil

Abstract

Efficient cleanup of viscous crude oil spill is a worldwide challenge due to its sluggish flowability at room temperature. Conventional oil remediation methods using physical absorbers, skimmers, and vacuum technologies either demonstrate low absorption efficiency or have severe operational restrictions. Inspired by the highly efficient and passive transpiration process in trees, a solar-heated carbon absorber (HC-Wood) with an inherited wood structure of aligned channels for rapid crude oil absorption is reported. The unique porous structure of the carbon absorber can extend the light absorption paths, guide the direction of heat transport, and decrease the resistance to oil flows, endowing the carbon absorber a large efficiency of solar absorption (>99% of the incident irradiation), excellent thermal management, and fast capillarity-driven oil absorption behavior. The low tortuosity of the porous structure together with the efficient solar-thermal conversion enable the absorber to demonstrate a crude oil absorption rate of 1550 mL m −2 in 30 s under 1 sun irradiation, which is 10 times faster than previously reported results for passive absorption of viscous crude oil. Given the unique structural design, low operating cost, and rapid oil absorption speed, this work provides a promising solution for addressing catastrophic large-area viscous oil spills.

Thick Electrode Batteries: Principles, Opportunities, and Challenges

“…With respect to low‐tortuosity pore structure engineering, nature is generally regarded as the master in making hierarchically straight pores that normally function as water and nutrient transport pathways since these structures are found in various natural plants . Such mass‐transporting pore structures in natural plants (e.g., tree) inspired researchers to develop thick electrodes inheriting the nature‐made low‐tortuosity pores .…”

Engineered Nanomaterials for Sustainable Oil Separation and Recovery

“…relied on bioinspiration from passive transportation process in trees to create a solar‐heated, wood‐derived, carbon absorber (HC‐Wood) with an aligned porous structure for cleanup of crude oil spills. The nanostructured material achieved a crude oil absorption rate of 1550 mL m −2 in 30 s under 1 sun irradiation (>99% solar absorption), 10 times faster than other passive crude oil absorption reports [59] . This was accomplished because of the innovative porous structure of the carbon absorber that: extended light absorption pathways, guided heat transport, and reduced oil flow resistance along the sorption route.…”

Harnessing Solar‐Driven Photothermal Effect toward the Water–Energy Nexus

“…For example, PPy-polyethylene glycol (PEG)-polymerized octadecylsiloxane (PODS) coated sponges were fabricated via two-step surface modification strategy, which takes full advantage of the photothermal property of PPy to heat the viscous oil, as well as the hydrophobic PODS to improve the adsorption capacity of sponges to viscous oil. [185] However, their major bottleneck is that the adsorbed crude oil required to be frequently squeezed out from the inner pores of sponges once the maximum adsorption capacity was reached. As a result, its adsorption capacity to viscous oil was increased by 32.6%, and the adsorption time was decreased by 40.0% compared with conventional sponges.…”

“…Thanks to the excellent photothermal effect of CNTs, the oil‐sponge interfacial temperature has a sharp rise to nearly 40 °C after 6 min, corresponding to a reduction of its viscosity from 10 5 to 4106 mPa s. This photothermal sponge has the ability of adsorbing almost of all the heavy oil (2.5 g) during 20 min light illumination ( Figure a) and could remain satisfied reusability and recyclability during five cycles of adsorption and desorption experiments. To further improve the adsorption rate of crude oil, Hu's group used modified natural wood with aligned channels as the photothermal sorbent to obtain a high crude oil adsorption rate of 1550 mL m −2 in 30 s under one sun irradiation, which is ten times faster than that of aforementioned example . However, their major bottleneck is that the adsorbed crude oil required to be frequently squeezed out from the inner pores of sponges once the maximum adsorption capacity was reached.…”