Which chemical absorbs oil?

Micro- and nanoporous materials capable of absorbing oil

From the results of a Google Search, it is found that various chemicals can effectively absorb oil. One prime example includes hydrophobic materials like zeolites, activated carbon, and synthetic polymers which have a strong affinity for oil and can effectively isolate oil from water surfaces.

Zeolites

Previous works (Carmody et al. 2007; Alayande et al. 2016) focused on the synthesis of hydrophobic zeolites as an alternative for activated carbon absorbents. Natural zeolites are aluminosilicate minerals with a 3-D structure. Their wide pores and large surface area facilitate the removal of impurities from water and air (Al-Haddad et al. 2007). Zeolites have been studied as absorbents for petroleum hydrocarbons, heavy metals, sulfur, and ammonia compounds. Tests have shown that natural and manufactured zeolites perform better in wastewater treatment, achieving an 84.4% removal of ammonia compounds compared to 15.6% by activated carbons.

In another study, Carmody et al. (2007) synthesized organo-clays using Wyoming Na-montmorillonite and various other compounds. These organo-clays exhibited higher oil absorption capacities with increased long-chain hydrocarbon content. However, the high cost, low biodegradability, and limited recyclability posed significant drawbacks.

Franco et al. (2014) found that nanosorbents functionalized with oil distillation residues and alumina nanoparticles could achieve high oil absorption capacity at neutral pH and a 4% load of vacuum residue. While economically advantageous, their use requires specific conditions to maximize absorption capacity.

Alayande et al. (2016) employed expanded polystyrene (EPS) and zeolites to synthesize beaded fibers with a zeolite matrix by electrospinning. These materials exhibited superhydrophobic properties and high oil absorption capacities due to the zeolite porous matrix. Figures 1, 2, and 3 illustrate several examples of surface morphology and water contact angles of these composite materials.

Figures

Fig. 1: Surface morphology of 20% EPS electrospun at...

Fig. 2: Surface morphology of EPS/zeolite film and EPS film...

Fig. 3: Water contact angle of EPS/zeolite and EPS...

Indeed, the high porosity and large surface area of zeolites are essential in the oil removal process. Additionally, hydrophobicity, absorption capacity, and retention of oil are crucial for cleaning impurities in wastewater, seawater, and other aquatic systems.

Aerogels

Aerogels are materials where the liquid component has been replaced with gas, resulting in an intact solid micro- or nanostructure containing ~99% air by volume (Zuo et al. 2015). Examples include silica-based, cellulose-based, clay-based, and carbon-based aerogels.

Silica-based aerogels, such as Cabot nanogels, have shown high oil absorption capacities. However, stable water-oil emulsions reduce their efficiency. Hence, sustainable materials such as plants and certain soils have been recommended as aerogel precursors for better renewable and environmentally friendly options.

Functionalized cellulose aerogel with TiO2 coating exhibits absorption capacities of 20-40 (wt of oil/wt of absorbent) and can be reused up to 10 times. For carbon-based aerogels, greener synthesis techniques are attracting attention, like the synthesis of graphene-carbon nanotube aerogel. Figures 5, 6, and 7 demonstrate the synthesis process and the interaction between graphene oxide and carbon nanotubes.

Figures

Fig. 5: Schematic diagram for synthesis of graphene-CNT aerogels...

Fig. 6: Adsorption of vegetable oil using graphene-CNT aerogels...

Fig. 7: Continuous adsorption and removal of gasoline from a non-turbulent water-oil system...

Clay-based aerogels combine the hydrophobicity of organo-clays and the porosity of aerogels. Under optimal conditions, they can achieve high absorption capacities and are recyclable. Figures 8 and 9 illustrate the pillow-type sorbent for oil spill cleanup.

Figures

Fig. 8: Pillow-type sorbent of clay polymer aerogel...

Fig. 9: Application of the pillow-type sorbent for oil spill clean-up...

Polymers

Common polymeric absorbents include polyurethane, polypropylene, polyethylene, and cross-linked polymers. Innovations in this area, such as carbon nanotube and polyurethane-based absorbents, have shown superhydrophobicity and high absorption capacity. These materials are recyclable up to 150 times without losing their efficiency.

Magnetic nanoparticles coated with polystyrene have been tested for oil absorption, showing selective absorption for oil when a magnet is used to remove the oil from water. The hydrophobic nanocomposite's absorption capacity was three times its own weight.

Poly(dimethylsiloxane) (PDMS) porous materials, synthesized using sugar particles, can absorb larger oil quantities quickly. Figures 13-25 show various examples of their structure and morphology.

Figures

Fig. 13: SEM images of sugar particles and PDMS oil absorbents...

Fig. 14: EV and EV/CNT hybrid morphology...

Fig. 15: Cross-sectional FE-SEM images of cotton fibers and CCFs...

Fig. 16: Floating-ability test of CCFs-400 after crude oil sorption...

Fig. 17: Behavior of a water droplet on pristine sawdust and superhydrophobic/superoleophilic sawdust...

Fig. 18: Sawdust product as an oil sorbent for separating water and gasoil mixture...

Fig. 19: Flexibility of the large-scale cellulose aerogel...

Fig. 20: Oil absorption process of the recycled cellulose aerogel...

Fig. 21: Preparation of MCF aerogel and its morphologies...

Fig. 22: Surface wettability of aerogels...

Fig. 23: Recyclability of MCF aerogel...

Fig. 24: Regeneration of MCF aerogel...

Fig. 25: Selective oil sorption with PDMS-coated absorbent cotton...

Natural and Natural-Based Products

Hydrophobic properties, absorption capacity, and buoyancy are critical in absorbents for oil spills. Most efficient absorbents include natural products like peat moss and modified natural absorbents such as coated cellulose. These materials offer eco-friendly options with good oil absorption and are often biodegradable.

Table 1

The table lists materials based on natural absorbents...

What Is Oil Absorbent Made Of?

Oil absorbents are designed to quickly soak up oils and other hydrocarbon liquids. They come in various forms suitable for different settings, from workshops to kitchens.

What Are Oil Absorbents?

These spill absorbents can come in different forms such as mats, socks, booms, and pillows, all typically white in color and having oleophilic and hydrophobic properties.

What Are Oil Absorbents Made From?

Oil absorbents can be made from organic materials like peat moss or clay, or synthetics like polypropylene, with each type offering unique absorbency properties and uses.

What Are Oil Absorbent Pads Made Of?

Oil absorbent pads and mats are often made of polypropylene, available in rolls or individual pieces. These pads are effective for spill response and easy to use.

What Are Granular Sorbents Made With?

Loose granular absorbents resemble coarse sand and are made from recycled or natural materials. They are useful for pouring over and soaking up oil spills.

Corn Cob

Corncob granules can hold up to four times their weight in liquids and are biodegradable.

Peat Moss

Peat moss is ideal for cleaning up oil spills on water or land and is also biodegradable.

Gran-Sorb

Made from paper mill waste, Gran-Sorb is versatile and effective on oils and lubricants.

Super Sorbent

Lightweight and non-toxic, Super Sorbent is suitable for various types of chemical spills.

What Are Absorbent Pillows, Socks, and Booms For Oil Spills Made From?

These absorbent products typically contain polypropylene fillers and are used in marine locations for hydrocarbon spills.

Final Thoughts

When dealing with spill response and cleanup, it's crucial to choose the right type of absorbents. Consider the type of spill, the time available for cleanup, and any residual cleanup required. For more information, visit our website oil absorbent felt.