Industrial Oily Wastewater Treatment Research Articles

Effective parameters on fabrication and performance of superhydrophobic/superoleophilic polyurethane sponge: Design of experiment approach

Referring to importance of the oil/water separation as one of the main challenges in the environmental conditions, numerous researches in the superhydrophobic/superoleophilic materials especially in the industrial oily wastewater treatment have been focused. In this study, the commercial polyurethane (PU) sponge was dip-coated by zinc stearate (Zn(St)2) particles and a novel adhesive of hexamethylenetetramine (HMTA) cured phenol-formaldehyde resin (PFR). For this purpose, a design of experiment (DOE) was applied to statistically specify the effect of important process variables on the final product properties. The second-order central composite design (CCD) approach based on the response surface methodology (RSM) analysis was conducted by changing namely the Zn(St)2 suspension concentration (2–4 wt%), PFR concentration (10–30 wt%), HMTA/PFR weight ratio (10–20 wt%), and sponge density (12, 15 and 17 kg∙m−3) on the key response output variables including oil and water absorption capacity of the Zn(St)2/HMTA cured PFR-coated PU. The optimal predicted results were experimentally verified and matched well to achieve the modified superhydrophobic PU sponge for the oil/water separation. The characterizations of the modified PU sponge by SEM, EDX mapping, FTIR, XRD, UV-Vis, BET, and TGA results confirmed that the Zn(St)2 uniformly covered the entire PU sponge. In addition, it showed a high demulsification capacity, the absorption capacity of various oil and solvents, and a water contact angle as high as 165° which was further approved to be oil wet in less than <10 millisecond. More importantly, the prepared modified superhydrophobic PU sponge presented an excellent reusability performance and chemical, thermal and mechanical stability in harsh conditions. This stable superhydrophobic PU sponge with the aforementioned outstanding properties is expected to be widely used for the practical oil/water separation.

Optimization of isotropic MoS2/PES membranes for efficient treatment of industrial oily wastewater.

Elimination of tiny oil droplets nearly miscible with wastewater can be realized using membrane technology through ultrafiltration. The novelty of this work was to blend different phases of molybdenum disulfide (MoS2) in isotropic polyethersulfone (PES). We prepared isotropic PES membranes by optimizing nonsolvent vapour-induced phase separation (VIPS). Membranes were blended with MoS2 nanosheets of different phases to promote separation performance and antifouling resistance. FE-SEM revealed the flower-like surface morphology of MoS2 nanosheets. HR-TEM of MoS2 revealed 2H domains in the monolayer, flakes of a few layers and a d-spacing of 0.22 nm. Raman spectroscopy could be used to distinguish mixed-phase MoS2 from single-phase MoS2. Isotropic PES membranes modified with 70% 1T/2H MoS2 had a significantly high permeance to pure water (6911 kg m-2 h bar). The same membrane possessed a high efficiency of oil rejection of 98.78%, 97.85%, 99.83% for emulsions of industrial crude oil at 100, 1000 and 10 000 mg L-1, respectively. Removal of oil droplets from wastewater was dominated by a mechanism based on size exclusion. Isotropic PES modified with 2H MoS2 possessed superior oleophilicity, which resulted in low rejection of crude oil. Modified membranes showed excellent fouling resistance for three successive filtration cycles, as evidenced by enhanced antifouling parameters. Our study reveals how the phase composition of MoS2 nanosheets can significantly affect the performance of isotropic PES membranes during the ultrafiltration of oily wastewater.

Oil/water separation copper membranes modified by laser induced ZnO nanowires growth with enhanced catalytic function

Oil/water separation is a significant area of scientific study, and also has significant practical applications in the treatment of industrial oily wastewater and oil spill pollution. In this study, the high-flux copper mesh is fabricated by laser in a Zn2+ precursor solution at room temperature. The copper mesh processed inside the solution has a higher flux than that processed in the air. The heat absorbed by the liquid promotes the growth of ZnO nanowires on the copper mesh surface. The copper mesh's underwater oil contact angle (OCA) is as high as 150°. Compared with conventional copper mesh, it has a higher stability and can maintain a contact angle of 150° in acid-base environments and high-temperature environments. It has hydrophilic and oleophobic properties and can be used for oil/water separation. After 50 oil/water separation cycles, the separation efficiency can keep higher than 97%. This new method exhibits excellent potentials for oil/water separation and oil purification attributed to its simple and ecologically friendly processing.

Industrial oily wastewater treatment by microfiltration using silver nanoparticle-incorporated poly (acrylonitrile-styrene) membrane

Membrane filtration exhibit operational limitations such as biofouling, which leads to concentration polarization and reduces permeability and selectivity, despite advantages such as low operating cost, high selectivity, and permeability. In recent years, the antibacterial properties of silver nanoparticles (AgNPs) have been investigated for improving membrane processes; however, the fouling phenomena in presence of AgNPs in the membrane matrix have not been fully discussed. Herein, the antifouling properties of a poly (acrylonitrile-styrene) copolymer incorporated with AgNPs were studied in a microfiltration membrane process. The Creighton method was used to synthesize AgNPs, and the effects of AgNPs on the porosity, morphology, pore size, mechanical strength, permeability, and selectivity of the membranes were investigated. Moreover, to investigate the biofouling of the obtained membranes, microfiltration of industrial oily wastewater was performed at constant pressure over three cycles. Using AgNPs in the membrane matrix resulted in enhanced antifouling properties of the copolymer membrane, which is related to the structure of the AgNPs in the casting solution, as proven by SAXS analysis. The results show that the CFU% for Staphylococcus aureus and E.coli reach 2% and 6%, respectively. Finally, the Derjaguin–Landau–Verwey–Overbeek (DLVO) thermodynamic model was applied to study the antifouling mechanism, correctly predict the separation behavior in the membrane, and design, simulate, and optimize the separation processes in the membrane separation plantsa. The DLVO model could predict the separation behavior in the synthesized membranes, and the poly(acrylonitrile-styrene) copolymer membranes containing AgNPs were proven have promising industrial wastewater treatment applications.

Facile fabrication of fabric-based membrane for adjustable oil-in-water emulsion separation, suspension filtration and dye removal

Special wettability fabrics-based membranes have shown excellent performance in emulsified oil/water separation, however, their application in separating industrial oil-in-water emulsions still remains a great challenge due to the complexity of multifarious surfactant components. In this work, we demonstrate a simple and facile approach to fabricate fabric-based membranes (P(AM-DMC-AA)@CFs) for complex emulsified oil/water (printing and dyeing wastewater) separation with combining the advantage of amphoteric polyacrylamide layer and cotton fabric in a single system. The amphoteric polyacrylamide surface and tortuous fabric channels synergistically provide the membranes with demulsification adjustability for separating emulsified oil in water which stabilized by anionic/cationic surfactants. Meanwhile, the incorporating of amphoteric polyacrylamide into cotton fabrics had remarkable advantages of both flexible and stable superhydrophilic/underwater superoleophobic. Consequently, the obtained P(AM-DMC-AA)@CFs membranes are endowed with robust superhydrophilicity, underwater superoleophobicity and switchable zeta potential, which make it capable of highly efficient separation of oil/water emulsion (anionic: 94.05%, cationic: 96.19%), suspension filtration (kaolin: 89.5%, hematite: 93.1%,) and concurrent dye removal in 5 min (14.3 mg/g). In addition, the prepared membrane is still effective in separating simulated printing and dyeing wastewater containing multiple pollutants. The facile and versatile design of the P(AM-DMC-AA)@CFs membrane offers new prospects for exploiting fabric-based membranes with extraordinary features for industrial oily wastewater treatment.

Customized copper/cobalt-rich ferrite spinel-based construction ceramic membrane incorporating gold tailings for enhanced treatment of industrial oily emulsion wastewater

New ceramic membranes (CM) using environment-oriented materials instead of rare materials are more attractive and easier to large-scale engineering and promotion. In this study, the feasibility of customizing low-cost and robust CM, is investigated by sintering typical available solid wastes (Fe-S-rich gold tailings and Si-rich marine shellfish powder) as the matrix with copper/cobalt-rich precursors. Analysis results indicate that the precursors (Cobaltate and Cuprate) with the proposed ratio (1:1 by mass, 1300 °C) can be chemically stable crystallized in the more durable structure of customized copper/cobalt-rich ferrite spinel-based construction CM (CM-(Cu-Co)Fe2O4). The composite membrane can operate stably and consumes no additional energy. After detailed characterization of the pore structure, the purification treatment of industrial oily wastewater (rejection rate > 99.9), emulsion oily wastewater (rejection rate > 97.9) and alizarin red wastewater (rejection rate > 99.3) was fully evaluated. Surprisingly, the waste-to-resource CM of CM-(Cu-Co)Fe2O4 exhibits significant heavy metal iron ion removal performance (>94%) due to electrostatic attraction and adsorption. The successful preparation and application of environment-oriented multifunctional CM from a typical solid waste matrix provide a promising strategy of resource recovery for beneficial utilization of ordinary solid wastes with stock as ceramic raw materials.

Selective and Continuous Oil Removal from Oil-Water Mixtures Using a Superhydrophobic and Superoleophilic Stainless Steel Mesh Tube.

The development of continuous oil-water separation processes has applications in the treatment of industrial oily wastewater and effective management of oil spills. In this research, the performance of a superhydrophobic-superoleophilic (SHSO) membrane in oil-water separation is investigated through dynamic tests. We investigate the effects of the total flow rate and oil concentration on the separation efficiency using an as-fabricated SHSO mesh tube. To construct the SHSO membrane, a tubular stainless steel mesh is dip-coated into a solution, containing a long-chain alkyl silane (Dynasylan F8261) and functionalized silica nanoparticles (AEROSIL R812). The as-prepared SHSO mesh tube illustrates a water contact angle of 164° and an oil contact angle of zero for hexane. A maximum oil separation efficiency (SE) of 97% is obtained when the inlet oil-water mixture has the lowest flow rate (5 mL/min) with an oil concentration of 10 vol %, while the minimum oil SE (86%) is achieved for the scenario with the highest total flow rate (e.g., 15 mL/min) and the highest oil concentration (e.g., 50 vol %). The water SE of about 100% in the tests indicates that the water separation is not affected by the total flow rate and oil concentration, due to the superhydrophobic state of the fabricated mesh. The clear color of water and oil output streams also reveals the high SE of both phases in dynamic tests. The outlet oil flux increases from 314 to 790 (L/m2·h) by increasing the oil permeate flow rate from 0.5 to 7.5 (mL/min). The linear behavior of the cumulative amounts of collected oil and water with time demonstrates the high separation performance of a single SHSO mesh, implying no pore blocking during dynamic tests. The significant oil SE (97%) of the fabricated SHSO membrane with robust chemical stability shows its promising potential for industrial-scale oil-water separation applications.

Preparation of cellulose/chitosan superoleophobic aerogel with cellular pores for oil/water separation

Nanofibrillated cellulose (NFC)/chitosan (CS) composite aerogel with underwater superoleophobicity was prepared by freeze-drying for oil/water separation. The soft-ice freezing technique was employed to construct cellular pores for improving the mechanical performance while enhancing mass transfer of freeze-drying. The dielectric-aided microwave heating was adopted to enhance heat transfer of freeze-drying. The results showed that the prepared NFC/CS aerogel exhibited an excellent mechanical property with a stress of 87.16 kPa at 80% strain, and underwater superoleophobicity with all oil contact angles above 150˚. The proposed drying method could save over 40% of drying time, achieving a simultaneous mass and heat transfer enhancement of freeze-drying. The prepared aerogel provided separation efficiencies of all above 99.96% and average permeate fluxes of 0.817 and 0.826 L·m−2·s−1 after 20 cycles for oil/water and oil/seawater separations. The research results are expected to provide an economical and sustainable solution for the industrial oily wastewater treatment.

Application of combined granular media with opposite wettability for demulsification of oily wastewater by microchannel filter

Oil-water separation with high efficiency and low energy consumption is a tremendous challenge in the green treatment of oily wastewater. In this paper, a novel filtration method with combined granular media for collaborative removal emulsified oil and suspended solids (SS) was proposed, followed by the exploration of demulsification feasibility and oil removal mechanism. The effect of the operation and structural parameters of the filter bed on oil separation performance was thoroughly investigated, and its feasibility for raw oily wastewater treatment was also explored. A remarkable demulsification performance was observed with the combined granular media filter, and a balance of separation efficiency and pressure drop in the emulsified oily wastewater filtration was also achieved subsequently. Effective oil droplet capture and coalescence were observed with a high speed camera system, and pore clogging could be avoided in combined media. The optimal parameters of the combined media filter (CMF) were concluded to be a combined media ratio of 1:1, a superficial velocity of 0.20 m min−1, and a bed porosity of 58.1%. The average oil and suspended solids concentrations in raw oily wastewater was decreased to 8.4 mg/L and 23.3 mg/L during the pilot-scale operation, which indicated that the novel filter composed of combined media had better performance in collaboratively removing oil and SS, even in the period of fluctuating influent parameters. It is believed that a novel and efficient oil removal method, especially including of emulsified oil removal was provided, which also shows great potential and value for the green treatment of industrial oily wastewater.

Surface modification of porous polyvinylidene fluoride hollow fiber membrane by sulfonated poly(ether ether ketone) coating for membrane distillation of oily wastewater

AbstractHighly porous polyvinylidene fluoride hollow fiber membranes were fabricated by a non‐solvent induced phase separation process. The membranes were modified by coating an ultra‐thin hydrophilic layer of sulfonated poly(ether ether ketone) (sPEEK) onto the inner surface. An industrial oily wastewater treatment was performed through an air gap membrane distillation (AGMD) process. From field emission scanning electron microscopy, the modified membrane showed an open structure with a large finger‐like outer layer and sponge‐like inner layer. The thickness of the coated sPEEK layer on the inner surface was about 0.5 μm. The coated membrane presented mean pore size of 36 nm and overall porosity of 73%. The inner surface water contact angle decreased from about 82° to 57°. Using Langmuir adsorption experiment, minor oil adsorption on the modified membrane surface was confirmed. A stable water flux of about 12 kg m−2 h−1 and oil rejection of 99% were found during 72 h of the AGMD process for treating the oily wastewater of NGL‐900 (Gachsaran, Iran) plant. The high flux recovery ratio of about 98% was related to the improved anti‐oil‐fouling property. The modified membrane can be a potential candidate for oily wastewater treatment through the MD processes.

Intelligent Coatings with Controlled Wettability for Oil-Water Separation.

Intelligent surfaces with controlled wettability have caught much attention in industrial oily wastewater treatment. In this study, a hygro-responsive superhydrophilic/underwater superoleophobic coating was fabricated by the liquid-phase deposition of SiO2 grafted with perfluorooctanoic acid. The wettability of the surface could realize the transformation from superhydrophilicity/underwater superoleophobicity (SHI/USOB) to superhydrophobicity/superoleophilicity (SHB/SOI), both of which exhibited excellent separation performance towards different types of oil–water mixtures with the separation efficiency higher than 99%. Furthermore, the long-chain perfluoroakyl substances on the surface could be decomposed by mixing SiO2 with TiO2 nanoparticles under UV irradiation, which could reduce the pollution to human beings and environment. It is anticipated that the prepared coating with controlled wettability could provide a feasible solution for oil–water separation.

Oily wastewater treatment by blend polyether imide‐sulfonated poly (ether ether keton) hollow fibre membrane through a side‐stream MBR process

AbstractThe blend polyether imide‐sulfonated poly (ether ether keton) (PEI‐sPEEK) hollow fibre membrane was prepared for oily wastewater treatment of the natural gas liquid plant (NGL‐900, Gachsaran, Iran) through a side‐stream membrane bioreactor (MBR) process. Using PEI/sPEEK ratio of 90/10, a good compatibility of PEI and sPEEK polymers was achieved by DSC analysis. The modified membrane showed an open structure with large finger‐likes, overall porosity of about 80% and mean surface pore size of 10 nm. In addition, the membrane hydrophilicity significantly improved as water contact angle reduced from about 82° to 58°. In the MBR process, the improved membrane presented oil rejection, COD, TSS and turbidity reduction of about 99.9%, 99.7%, 98.9%, and 99.7%, respectively. The membrane showed a good antifouling property with flux recovery ratio (FRR) of 80.2% where the cake filtration was the dominant fouling mechanism. The modified membrane can be a promising alternative for treatment of industrial oily wastewater due to the enhanced properties.

Facile fabrication of porous waste-derived carbon-polyethylene terephthalate composite sorbent for separation of free and emulsified oil from water

Containment of oil spills in aquatic bodies and treatment of oily wastewater are necessary to mitigate oil pollution. Synthetic oil sorbents are commonly used for managing oil spills and while they are effective, their usage introduces a considerable amount of non-biodegradable plastic into the environment. In an effort to develop an inexpensive sorbent by reutilizing solid wastes for a sustainable future, this study investigates the fabrication of a composite oil sorbent from used polyethylene terephthalate bottles and waste carbonaceous residue from the gasification of oil refinery bottoms via an energy efficient phase inversion method. The composite sorbent demonstrated oil sorption capacity of ∼ 8 g/g, which is comparable to some commercially available adsorbents, and excellent retention capacity for mineral, paraffin and crude oils of different viscosities. Furthermore, the composite is able to remove oil from mineral or paraffin oil-in-water emulsions by sorption, with an efficacy of > 99.7 %, indicating its promising application in the treatment of industrial oily wastewater. Cost analysis shows that this waste-derived composite can be produced commercially at a competitive price.

Simultaneously achieving high-effective oil-water separation and filter media regeneration by facile and highly hydrophobic sand coating

Efficient oil-water separation, including of emulsified oil separation, is one of the problems restricting the green development of the petrochemical industry. Herein, highly hydrophobic sand was fabricated in one-step, followed by an investigation of adsorption capacity for various oils of hexane, petroleum ether, diesel, tetrachloroethylene and tetrachloromethane. The modified sand (MS) filter bed was subsequently set up to investigate the oil separation efficiency for oil-water mixtures, emulsions and actual petroleum refinery wastewater, respectively. Moreover, the capture process of the oil droplet by the MS was observed by a high-speed camera system, and the oil removal mechanism was explored. The removal feasibility of the oil adhered to the MS in a hydrocyclone was also investigated. The oil could be quickly adsorbed by the MS, and the adsorption capacity was positively correlated with oil density. A high flux of 14,436 L·m−2·h−1 and a considerable separation efficiency of 99% were obtained when the MS was applied for oil-water mixture separation. Additionally, the highest separation efficiency of various emulsions was up to 99.3%. Regrading actual petroleum refinery wastewater, the oil removal efficiency of the MS reached 90% rather than 57.8% of raw sand. The oil droplets in the wastewater were efficiently separated by the MS based on the mechanism of adsorption and coalescence. Additionally, the oil adhered on the MS could be removed, and the oil concentration decreased from 17.6% to 5.2%, which was ascribed to the MS spinning in a hydrocyclone. A novel oil-water separation method of hydrocyclone-intensified filtration by facile and highly hydrophobic sand coating was proposed, and simultaneously the filter media can be effectively regenerated. It is believed that this work might provide a low cost, recyclable and efficient strategy for oil removal, which shows high promise for industrial oily wastewater treatment.

A facile preparation of robust superhydrophilic and underwater superoleophobic copper foam for high efficiency and repeatable oil–water separation

Design of robust separation materials with superwettability for efficient oil–water separation is of great significance because of the serious problem of oil leakage. Herein, we have fabricated a superwetting material based on copper foam via chemical oxidation and hydrothermal method for oil–water separation. These modified copper foam with rough structure exhibit excellent superhydrophilicity and underwater superoleophobicity. Thus, it shows high oil–water separation efficiency (99%), excellent circulation and high‐flux (24,129 Lm−2 h−1). Meanwhile, the modified copper foam exhibits favorable durability and stability under extreme environment conditions, such as immersion tests in salt, different pH conditions, high temperature and mechanical abrasion tests. Therefore, the modified copper foam has the advantages of high separation efficiency and remarkable stability, and is promising material, which can be used for the treatment of industrial oily wastewater.

One-step preparation of tubular nanofibers and micro/nanospheres covered membrane with 3D micro/nano structure for highly efficient emulsified oil/water separation

Facile fabrication of superwetting materials is urgently desired, which remains a challenging issue for industrial oily wastewater treatment. In this study, a novel tubular nanofibers and micro/nanospheres covered PVDF/graphene (GE) composite membrane (TPGCM) was prepared via one-step simultaneous electrospinning/electrospraying process with the polyethylene terephthalate (PET) braided tube (BrT) as the support. This simple combined technique allowed the uniform integration of PVDF micro/nanospheres and GE nanosheets into the PVDF nanofibrous network to form a 3D hierarchical micro/nano structural composite membrane. The resultant membrane exhibited superoleophilicity in air with oil contact angle of 0°, and showed under oil superhydrophobicity with corresponding contact angle of 159 ± 0.8°. Furthermore, the morphology of the covered micro/nanospheres was simply controlled by adjusting GE nanosheets content in electrospraying precursor. As-prepared TPGCM can effectively separate a series of Span-80-stabilized water-in-oil emulsions, which showed outstanding separation efficiency of up to 99.8 %. Moreover, the robust recyclability was also presented with separation efficiency of more than 99.3 % after 10 cycles. Our strategy possesses the advantages of simplicity and cost saving, avoiding complicated reaction or post treatment, thus indicating its scalable application for practical oily wastewater purification.

Photocatalytic demulsification of oil/water emulsions containing nonionic surfactant.

Separation of oil-water (OW) emulsions is investigated using a photocatalytic demulsification approach. Experiments were conducted using two types of photocatalysts, namely, ZnO and TiO2. The emulsion samples were prepared with oil to water ratios of 1:3, 1:1, and 3:1 and using nonionic surfactant Tween 20 as an emulsifier. The demulsification efficiency was determined using a direct time varying phase separation measurement, while dynamic light scattering (DLS) and microscope imaging (MI) were used to determine the change in emulsion droplets size. The investigation results showed that all the emulsions were destabilized and separated within 30-90min with demulsification efficiency that ranged from 38 to 90%. On the other hand, untreated control samples remained stable with no phase separation for more than 24h. For most of the studied experimental conditions, TiO2 nanoparticles gave better demulsification results than ZnO. Modeling of the batch demulsification kinetics for both systems agreed satisfactorily with the experimental measurements. This could allow its further extension towards design of continuous processes for potential implementation in treatment of industrial oily wastewaters.

Magnesium stearate-coated superhydrophobic sponge for oil/water separation: Synthesis, properties, application

Separation of an oil/water mixture has become a very attractive subject due to frequent oil spill incidents and industrial oily wastewater treatment. In this study, a robust superhydrophobic/superoleophilic polyurethane sponge comprising magnesium stearate coating and phenol-formaldehyde resin was developed by the cost-effective immersion method for the removal of organic materials and oils from the oil/water system. The characterizations of the modified polyurethane by SEM, FESEM, FTIR, Raman and EDX confirmed that it was well coated with phenol-formaldehyde and magnesium stearate. The water contact angle measurement results showed a contact angle exceeding 175° and sliding angle less than 3°, which are, compared to other reports up to now, a great unprecedented achievement. Also, no considerable change after abrasing and immersing in the acidic and basic solution was observed. Due to outstanding water contact angle, the organic absorption time is less than 1 s, covering a wide absorption capacity range of 19–38 g/g depending on the viscosity and density of oils and organic solvents. Finally, the modified polyurethane sponge provided an excellent performance capability of the continuous oil/water separation, required for an industrial application.

Tannin-inspired robust fabrication of superwettability membranes for highly efficient separation of oil-in-water emulsions and immiscible oil/water mixtures

In this work, a simple and facile approach was developed to modify hydrophobic polyvinylidene fluoride (PVDF) microfiltration membrane with superhydrophilicity and excellent underwater anti-oil adhesion properties. The approach involves a rapid deposition of tannic acid (TA) on the membrane surface followed by its oxidation by sodium periodate (NaIO4). The modified membrane not only showed a promising oil/water separation (greater than 98%) with an average water flux ranging from 38 ± 13 to 401 ± 97 L/m2-h for different kinds of surfactant-stabilized oil-in-water emulsions driven by vacuum pressure but also exhibited excellent recyclability and chemical stability. The modification method is versatile, can be applied on different types of substrate materials, such as non-woven textile and mesh, and thus has a great potential to fabricate materials at large-scale for industrial oily wastewater treatment.

Facile preparation of fluorine-free superhydrophobic/superoleophilic paper via layer-by-layer deposition for self-cleaning and oil/water separation

Oil/water separation is highly desired due to increasing industrial oily wastewater and frequent oil spill accidents. Here, superhydrophobic/superoleophilic paper was successfully fabricated by the combination of layer-by-layer (LBL) deposition of chitosan (CS) and hexadecyltrimethoxysilane (HMTS)-g-TiO2 on paper surface and subsequent heat treatment. The formation of CS/HTMS-g-TiO2 multilayers on modified papers was characterized. The wettability and physical strength of the modified papers were also examined. The paper modified with (CS/HTMS-g-TiO2)20 multilayers followed by heat treatment showed superhydrophobicity with a water contact angle of 167.4° and superoleophilicity with an oil contact angle of 0°. This paper had comparable tensile strength to that of original paper and excellent self-cleaning performance. The as-prepared paper could also effectively separate both immiscible oil–water mixtures and water-in-oil emulsions solely driven by gravity. The obtained paper exhibited stable recyclability, high environmental and mechanical durability. Therefore, this LBL-modified paper could be useful for oil spill cleanup and industrial oily wastewater treatment.