Composite Separation Membranes Research Articles

Robust and water-selective natural-cellulose-nanofiber-reinforced polyvinyl alcohol composite membranes for pervaporation of isopropanol/water mixtures

High-strength polyvinyl alcohol (PVA)–6-cellulose nanofiber (CNF) composite membranes for pervaporation separation of isopropanol (IPA)/water mixtures were produced using a solution casting method. Their morphological and physicochemical properties were evaluated using field emission scanning electron microscopy, atomic force microscopy, attenuated total reflection–Fourier-transform infrared spectroscopy, and X-ray diffraction. Upon the addition of various concentrations of CNF to PVA membranes, the tensile strengths of the PVA–CNF composite membranes increased with increasing CNF loading from 35.01 MPa for the pristine PVA membrane to 80.98 MPa for the membrane with an CNF loading of 10 wt% owing to the interactions between PVA and CNF. The effect of CNF loading was examined using pervaporation experiments, and the results indicated that the flux values of the membranes increased and their separation factors decreased with increasing CNF loading. The optimized membrane (PC-6 with a CNF loading of 6 wt%) presented stable pervaporation performance with a flux of 20-21 g/(m2h) and water content in the permeate of 20-21 g/m2h and 99.90±0.10 % after 120 h of operation at 40°C for a IPA/water feed of 85/15 (w/w). In summary, the high-strength water-selective PVA–CNF membranes fabricated in this study are promising for pervaporation separation of IPA/water mixtures.

Techno-Economic Optimization of Multistage Membrane Processes with Innovative Hollow Fiber Modules for the Production of High-Purity CO2 and CH4 from Different Sources.

Within the current climate emergency framework and in order to avoid the most severe consequences of global warming, membrane separation processes have become critical for the implementation of carbon capture, storage, and utilization technologies. Mixtures of CO2 and CH4 are relevant energy resources, and the design of innovative membranes specifically designed to improve their separation is a hot topic. This work investigated the potential of modified polydimethylsiloxane and ionic liquid–chitosan composite membranes for separation of CO2 and CH4 mixtures from different sources, such as biogas upgrading, natural gas sweetening, or CO2 enhanced oil recovery. The techno-economic optimization of multistage processes at a real industrial scale was carried out, paying special attention to the identification of the optimal configuration of the hollow fiber modules and the selection of the best membrane scheme. The results demonstrated that a high initial content of CH4 in the feed stream (like in the case of natural gas sweetening) might imply a great challenge for the separation performance, where only membranes with exceptional selectivity might achieve the requirements in a two-stage process. The effective lifetime of the membranes is a key parameter for the successful implementation of innovative membranes in order to avoid severe economic penalties due to excessively frequent membrane replacement. The scale of the process had a great influence on the economic competitiveness of the process, but large-scale installations can operate under competitive conditions with total costs below 0.050 US$ per m3 STP of treated feed gas.

Role of silane grafting in the development of a superhydrophobic clay-alumina composite membrane for separation of water in oil emulsion

Hydrophobic composite kaolin-coated clay-alumina membranes are unique choices for water in oil emulsion separation. In this work, a membrane fabrication approach is presented using kaolin clay coating in the clay-alumina tubular composite support tube and subsequently grafting by different concentrations of fluoroalkyl silane (FAS: 1H, 1H, 2H, 2H, -Perfluorooctyltriethoxysilane) on the membrane surface. Different concentrations of fluoroalkyl silane formed distinctive hierarchical structures which exhibited hydrophobicity of the membrane surface. The pore property, surface roughness properties, and thermogravimetric properties can be suitably tailored by tuning the silane concentration in the grafting solution. The surfaces of comparatively higher silane content grafted (M50 and M100) composite membranes were found to be superhydrophobic. Comparably, our optimal composite membrane (M100) displayed a moderate steady flux rate of 80-100LMH (Lm−2h −1) and excellent water rejection (>99%) properties during the separation of water in hexane and toluene emulsion at a cross-flow transmembrane pressure of 1 bar. The role of silane concentration on permeated hexane and toluene flux rate, water rejection rate, surface wettability, microstructure, and hydrophobic stability reveals new distinguishing insights into the hydrophobic clay-alumina composite membrane fabrication.

High-efficiency graphene oxide membranes intercalated by hollow TiO2 nanospheres and CNS@LDH composite spheres for enhancing dye separation from wastewater

Textile wastewater pollution with dyes has become a major source of water pollution. In the study, GO and composite nanospheres (CNS@LDH and HOTiO2) were used to form the composite materials by electrostatic self-assembly method, and the composite materials vacuum filtration on the surface of CA membrane to prepare the composite membranes for dyes separation. Among them, GO was used as a vertical separation layer in dyes separation, while the hollow structure of HOTiO2 nanosphere with a large specific surface area provided more adsorption sites, and the CNS@LDH nanosphere with core–shell structure played the role of expanding GO sheets and preventing HOTiO2 from collapsing. Compared with the GO membrane, the water flux of three dyes produced by GO/HOTiO2/CNS@LDH composite membrane increased by 18 times with a rejection rate of 99%. In addition, after 10 cycles of experiments, GO/HOTiO2/CNS@LDH composite membrane retained a rejection rate of over 98% with the flux of 79 L∙m−2∙h−1∙bar−1 for MB. GO/HOTiO2/CNS@LDH composite membrane retained a stable rejection rate on three dyes under extreme pH and ionic strength conditions. The composite membrane combined the adsorption and isolation effects of GO, HOTiO2, and CNS@LDH, which significantly enhanced the separation performance of dye wastewater. Accordingly, the GO/HOTiO2/CNS@LDH composite membrane has great potential in practical wastewater treatment.

Superhydrophilic and underwater superoleophobic in-situ derived 2D Ni-Fe MOF/HNTs composite-enhanced polyvinyl alcohol (PVA) hydrogel membrane for gravity-driven oil/water separation

In this work, we successfully prepared the 2D Ni-Fe MOF-HNTs composites by in-situ hydrothermal growth, followed by enabling it to full into PVA hydrogels, thereupon fabricating the oil/water separation 2D Ni-Fe MOF-HNTs/PVA-decorated stainless steel mesh. The structures and mechanical properties of the composites were identified by a series of characterizations. The results showed that the 2D Ni-Fe MOF nanosheets were gown on the outer surface of HNTs to form the exclusive composite structure and the 2D Ni-Fe MOF-HNTs/PVA composite membrane possessed a more compact pore structure, which exhibited the outstanding mechanical performance and the fatigue resistance ability. The surface property characterizations demonstrated that the 2D Ni-Fe-MOF-HNTs/PVA composite membrane had the superhydrophilic and underwater superoleophobic features. Ultimately, the results of the water flux and separation efficiency on 2D Ni-Fe-MOF-HNTs/PVA composite membrane for oil-water separation and emulsion separation corroborated that it was a promising high-performance separation composite membrane.

Monoamine‐modified thin film composite nanofiltration membrane for permselective separation of fermentation bioproducts

AbstractOne process involved in biorefinery for generation of value‐added products is fermentation. After fermentation, the downstream bioproduct purification process is conventionally performed by organic solvent extraction, which is environmentally‐hazardous and costly. Membrane‐based separation is a cost‐efficient and environmentally‐benign method for bioproduct separation and purification. In this study, a thin film composite (TFC) nanofiltration (NF) membrane was prepared and the pore size and charge of the polyamide layer were controlled by introducing iminodiacetic acid (IDA), a charged monoamine monomer, with piperazine (PIP) during interfacial polymerization (IP). The newly‐developed NF membrane was found to have a molecular weight cut‐off (MWCO) of 500 to 1350 Da, allowing the permeation of the fermentation product, while rejecting other higher molecular weight compounds. IDA addition in the aqueous amine solution during IP effectively engineered the MWCO values and pore sizes of TFC NF membranes for specific applications, such as separation of fermentation bioproducts. This study successfully showed that IDA reduced the diffusivity of PIP during IP, which negatively affected the polyamide formation and membrane performance. The optimal PIP:IDA concentration ratio was determined by MWCO and effective pore diameter for effective bioproduct separation and purification, which could not be performed by the current commercially‐available NF membranes.

Super-hydrophobic/super-oleophilic carbon nanofiber-embedded resorcinol-formaldehyde composite membrane for effective separation of water-in-oil emulsion

A super-hydrophobic/super-oleophilic carbon nanofibers (CNFs)-embedded resorcinol-formaldehyde (RF)-activated carbon fiber (ACF) composite membrane is synthesized for the efficient removal of water from a water-oil emulsion. Chemical vapor deposition (CVD) with copper oxide (CuO) as the catalyst is used to form CNFs for the first time over an ACF-supported RF polymeric layer. The prepared CuO–CNF/RF-ACF membrane was physicochemically characterized as super-hydrophobic/super-oleophilic (water contact angle 157° and oil contact angle 0°), attributed to the high surface roughness (Ra ∼55.56 nm) and graphitic content of the CNFs. The membrane had an asymmetric internal structure with a hydrophobic CNF-decorated microporous surface, which facilitated oil to pass and rejection of water droplets from the emulsion. The dead-end separation test data indicated a flux of 426 ± 20 L/m2-h with the water removal efficiency of 99.7% and the permeate having water droplets with the size range of 37–78 nm when tested against a water-oil emulsion of 10% (v/v) comprising 700–1700 nm sized water droplets. The physicochemical characterization, including the tests under harsh conditions showed the material mechanically, thermally, and chemically stable. The method described in this study to synthesize CuO–CNF/RF-ACF membrane is facile and has a potential for scale-up.

Superhydrophilic photocatalytic g-C3N4/SiO2 composite membranes for effective separation of oil-in-water emulsion and bacteria removal

Conventional membrane processes, e.g., microfiltration and ultrafiltration, suffer from severe permeation flux decline and fouling during the oily wastewater treatment. The superhydrophilic surface decoration provides an important and effective strategy to address this challenge. Herein, a surperhydrophilic/underwater superoleophobic nanocomposite surface with the photocatalytic properties was constructed via one-step facile vacuum-assisted filtration of a g-C3N4 nanosheet/SiO2 nanoparticle dispersion onto a microfiltration membrane substrate. Specifically, with the intercalation of 20 mg∙L−1 SiO2 nanoparticles into the g-C3N4 nanosheets, the g-C3N4/SiO2 composite membrane showed the superhydrophilic/underwater superoleophobic properties with an underwater oil contact angle of 170.0 ± 0.3°. Such a g-C3N4/SiO2 composite membrane yielded a permeation flux of >1290 LMH·bar−1 with an oil rejection of >99.91% during the vacuum filtration of oil-in-water emulsions. The g-C3N4/SiO2 composite membrane significantly outperformed the pristine microfiltration substrate that had severe fouling caused by oil blockage. Additionally, the g-C3N4/SiO2 composite membrane not only effectively retained the E. coli bacteria through size exclusion effect, but also promoted the inactivation of bacteria via visible-light photocatalysis. Therefore, our membrane has a great promise in practical oily wastewater treatment due to its excellent separation performance and biofouling resistance.

Zirconia Toughened Alumina-Based Separator Membrane for Advanced Alkaline Water Electrolyzer.

Hydrogen is nowadays considered a favorable and attractive energy carrier fuel to replace other fuels that cause global warming problems. Water electrolysis has attracted the attention of researchers to produce green hydrogen mainly for the accumulation of renewable energy. Hydrogen can be safely used as a bridge to successfully connect the energy demand and supply divisions. An alkaline water electrolysis system owing to its low cost can efficiently use renewable energy sources on large scale. Normally organic/inorganic composite porous separator membranes have been employed as a membrane for alkaline water electrolyzers. However, the separator membranes exhibit high ionic resistance and low gas resistance values, resulting in lower efficiency and raised safety issues as well. Here, in this study, we report that zirconia toughened alumina (ZTA)–based separator membrane exhibits less ohmic resistance 0.15 Ω·cm2 and low hydrogen gas permeability 10.7 × 10−12 mol cm−1 s−1 bar−1 in 30 wt.% KOH solution, which outperforms the commercial, state-of-the-art Zirfon® PERL separator. The cell containing ZTA and advanced catalysts exhibit an excellent performance of 2.1 V at 2000 mA/cm2 at 30 wt.% KOH and 80 °C, which is comparable with PEM electrolysis. These improved results show that AWEs equipped with ZTA separators could be superior in performance to PEM electrolysis.

Mussel-inspired fabrication of superior superhydrophobic cellulose-based composite membrane for efficient oil emulsions separation, excellent anti-microbial property and simultaneous photocatalytic dye degradation

Flexible multiple functional cellulose-based membrane (CM) for oil/water separation, anti-microbial and photodegradation are in great demand in marine wastewater treatment due to its’ effective and ecologically benign. Based on this requirement, MnO2 micro/nanoparticles were in situ deposited on CM sample surface followed by decoration of stearic acid (STA) for very effective oil/water separation, anti-fouling, and dye photodegradation triggered by visible light. The results demonstrated that this as-prepared CM sample showed superhydrophobicity with a water contact angle of 162 ± 2° and superoleophilicity with an oil contact angle of 0°. It also demonstrated exceptional high stability in hostile environments (acid and alkali solution, high temperature, wear resistance, underwater writing, self-cleaning) and a 2.6% increase in tensile strength. In addition, it can successfully separate emulsified oils from typical oil-in-water emulsions with good separation efficiency all over 98% and comparatively high flux (145.8 L·m−2·h−1). After 8 cycles, the separation efficiency of the n-hexane/water emulsion is still over 98%. Moreover, over 98% of MB was degraded by using superhydrophobic CM sample, indicating strong photocatalytic activity. Meanwhile, in the maritime environment, this biomimetic sample decreased the adherence of green algae by more than 95%, demonstrating strong anti-biofouling adhesion potential. It indicates that this cost-effective, scalable, environmental friendly, and efficient methodology presented superhydrophobic CM sample has the potential to promote the widespread development of multipurpose superwetting materials, with enticing potential for the treatment of complex oily wastewater.

Super-Hydrophobic/Super-Oleophilic CNF-Embedded RF-ACF Composite Membrane for Effective Separation of Water-in-Oil Emulsion

Super-Hydrophobic/Super-Oleophilic CNF-Embedded RF-ACF Composite Membrane for Effective Separation of Water-in-Oil Emulsion

Development of polydimethylsiloxane composite membrane for organic solvent separation

Membrane processes have proven to be energy-efficient technologies for separation of various substances, including organic solvents. In this study, crosslinked polydimethylsiloxane (PDMS) composite membranes were developed for organic solvent separation. Precursor solutions containing double-ended vinyl PDMS with four different molecular weights were spin-coated onto a polyethersulfone membrane substrate, and the crosslinking reaction was accelerated by heat treatment to produce PDMS composite membranes. The influence of the PDMS molecular weight and crosslinking on the membrane properties and performance was tested. It was shown that less swelling, more selective hexane absorption, and increased separation coefficient was observed with decreasing PDMS molecular weight. The trade-off relationship between the permeance and the separation coefficient was observed as the membranes prepared with lower molecular weights of PDMS showed lower permeability and higher separation coefficient. The separation coefficient showed a maximum value at a supplied ethanol concentration of 50 wt%. In addition, various solvent mixtures containing hexane and alcohols were used for organic solvent separation performance test using the PDMS composite membranes. A correlation was observed between the separation coefficient and the difference of χ parameters between alcohol/PDMS and hexane/PDMS. The mechanisms for solvent permeation and separation were discussed based on the interaction parameters, membrane swelling and solvent dissolution. The results of this study could be used as guidelines for the development of solvent-resistant PDMS composite membranes.

NH2-MIL-125@PAA composite membrane for separation of oil/water emulsions and dyes

Simultaneous removal of petroleum and dye pollutants posed a huge challenge to the development of membranes. NH 2 -MIL-125 was widely used in separation membranes, but so far had not been used for oil/water separation. We successfully prepared NH 2 -MIL-125@polyacrylic acid (referred to as NH 2 -MIL-125@PAA) composite membrane on the PVDF by vacuum-assisted self-assembly technology. Due to the introduction of a large number of hydrophilic nanoparticles on the PVDF, the composite membrane exhibited excellent hydrophilicity and underwater oleophobic properties. At the same time, the membrane could efficiently separate oil/water emulsions and dyes. After 10 cycles, the separation rate of the oil/water emulsions and the dye was above 99%, and the flux was above 400 L / m 2 ∙ h . Moreover, due to the successful cross-linking of PAA and NH2-MIL-125, the membrane had good stability. Therefore, the composite membrane in this study provided an idea for the removal of multi-component pollutants. • For the first time, NH 2 -MIL-125 composite membrane was used to oil/water emulsions separate. • The composite membrane can remove both oil/water emulsion and dye simultaneously. • After 10 cycles, the separation rate of the oil/water emulsions and the dye was above 99%.

Graphene-based composite membranes for isotope separation: challenges and opportunities

Abstract Graphene-based membranes have got significant attention in wastewater treatment, desalination, gas separation, pervaporation, fuel cell, energy storage applications due to their supreme properties. Recently, studies have confirmed that graphene based membranes can also use for separation of isotope due to their ideal thickness, large surface area, good affinity, 2D structure etc. Herein, we review the latest groundbreaking progresses in both theoretically and experimentally chemical science and engineering of both nanoporous and lamellar graphene-based membrane for separation of different isotopes. Especially focus will be given on the current issues, engineering hurdles, and limitations of membranes designed for isotope separation. Finally, we offer our experiences on how to overcome these issues, and present an ideas for future improvement and research directions. We hope, this article is provide a timely knowledge and information to scientific communities, and those who are already working in this direction.

A chemically stable La0.2Sr0.8Fe0.9Mo0.1O3-δ-molten carbonate dual-phase membrane for CO2 separation

We report here a mixed oxygen ionic-electronic conductor-molten carbonate composite membrane for high temperature CO2 separation. Mo-doping at Fe-site of La0.2Sr0.8FeO3-δ (LSF) is attempted to address its stability issue in CO2 or carbonate-containing environment. The La0.2Sr0.8Fe0.9Mo0.1O3-δ (LSFM)-molten carbonate membrane with 1 mm thickness delivers a CO2 permeation flux of 1.57 × 10−3 mol m−2 s−1 at 800 °C with 50% CO2 + 50 % N2 (total 1 atm) as feeding gas and pure He (1 atm) as sweeping gas, compared to 0.737 × 10−3 mol m−2 s−1 for the LSF counterpart. The CO2 permeation flux further increases to 2.25 × 10−3 mol m−2 s−1 for membrane prepared with Al2O3 coated LSFM substrate. An even higher CO2 permeability of 2.69 × 10−3 mol m−2 s−1 is demonstrated for LSFM-molten carbonate membrane at 800 °C when using simulated flue gas (15% CO2 + 10% O2 + 75 % N2 in total 1 atm) as feeding gas. The membrane also exhibits relatively stable CO2 and O2 fluxes during 50 h test at 750 °C. The designed LSFM-molten carbonate membrane can be potentially used as a reactor for dry methane reforming and partial oxidation of methane with flue gas as direct feedstock.

Multilayered molecularly imprinted composite membrane based on porous carbon nanospheres/pDA cooperative structure for selective adsorption and separation of phenol

Molecularly imprinted composite membrane (MIM) for selective separation of specific compound has broad applications for wastewater treatments. Herein, a multilayered molecularly imprinted composite membrane (m-MIM) with porous carbon nanospheres/polydopamine (pDA) cooperative structure was proposed to improve phenol selective adsorption efficiency. pDA layer was previously synthesized on the basal membrane to augment interfacial adhesion. Subsequently, carbon nanospheres were uniformly and firmly loaded on the double sides of pDA-modified membrane, whose active surface provided more distribution sites for imprinted cavities. The abundant hydroxyl and amino groups on pDA can enhance the hydrophilicity and imprinting activity of m-MIM, which promote mass transfer and adsorption. The characterizations including SEM, FTIR, XPS, and AFM confirmed the formation of cooperative structure on the basal membrane. The BET result show that the specific surface area of m-MIM was about 2.72 times that of basal membrane, and in term of hydrophilicity, water contact angle decreased from 46° (basal membrane) to 29°. Attributed to the abundant imprinted cavities, m-MIM acquired excellent adsorption capacity (51.40 mg g−1) and high permselectivity coefficients (more than 7.6). m-MIM remained stable adsorption capacity after nine cycles, which provides potential for water treatment and selective separation of specific substances. Mechanism of selective separation was unveiled by molecular simulation.

A novel composite membrane for simultaneous separation and catalytic degradation of oil/water emulsion with high performance

It is of great significance to develop novel membranes with dual-function of simultaneously separating oil/water emulsion and degrading the contained water-miscible toxic organic components. To meet this requirement, a dual-functional Ni nanoparticles (NPs)@Ag/C-carbon nanotubes (CNTs) composite membrane was fabricated via electroless nickel plating strategy in this study. The as-prepared composite membrane possessed superhydrophilicity with water contact angle of 0° and splendid underwater oleophobic property with oil contact angle of 142°. When the membrane was applied for separation of surfactant stabilized oil-in-water emulsion, high permeate flux (about 97 L m−2·h−1 under gravity), oil rejection (about 98.8%) and antifouling property were achieved. Benefitting from the NiNPs@Ag/C-CNTs layer on membrane surface, the composite membrane exhibited high catalytic degradation activity for water-miscible toxic organic pollutant (4-nitrophenol) with addition of NaBH4 in a flow-through mode. Meanwhile, the NiNPs@Ag/C-CNTs composite membrane possessed excellent durability, which was verified by the good structural integrity even under ultrasonic treatment. The cost-efficiency, high separation and degradation performance of the prepared membrane suggested its great potential for treatment of oily wastewater.

Robust PVA-GO-TiO2 composite membrane for efficient separation oil-in-water emulsions with stable high flux

Most super-wetting membrane materials are susceptible to oil pollution after separation process, causing a serious degradation of the separation ability. The rough structure of underwater superoleophobic membrane can effectively improve anti-fouling property, thus achieving stable separation. Herein, a composite polyvinyl alcohol-graphene oxide-titanium dioxide (PVA-GO-TiO2, PGT) membrane with rough structure is prepared through a simple hydrothermal and suction-filtration method. The as-prepared PGT membrane displays outstanding underwater superoleophobicity even for high-adhesion crude oil. Moreover, the as-fabricated membrane exhibits efficient oil-in-water emulsions separation performance with separation efficiency of larger than 99.1% and permeation flux of over than 762 L m−2 h−1 even after 10 min. Besides, the PGT membrane could separate various oil-in-water emulsions in corrosive environments with separation efficiency of higher than 99.3% and permeation flux of more than 760 L m−2 h−1. More importantly, the as-prepared membrane could keep the underwater superoleophobicity after sanding test (200 times) and bending test (500 times). The composite membrane with excellent oil-in-water emulsions separation performance, corrosion resistance and mechanical stability has broad prospects in the field of water purification.

Strategies to modify the structure of thin‐film composite membranes for advanced separation of metronidazole antibiotic from wastewater

AbstractIn this research, thin‐film composite (TFC) membranes were used for separating metronidazole antibiotic from effluents. In order to enhance the metronidazole separation performance, thin‐film nanocomposite (TFNC) membranes containing copper sulfide nanoparticles as well as modified thin‐film nanocomposite (MFTNC) membranes containing copper sulfide nanoparticles coated with acrylic acid were employed. The spherical morphology of CuS nanoparticles along with the acrylic acid chains coated on their surface was confirmed through TEM, scanning electron microscopy (SEM) and energy dispersive X‐Ray spectroscopy (EDS) analysis. The crystalline size of nanoparticles was obtained as 29 nm according to XRD. The effect of nanoparticles on chemical functional groups and membrane elemental analysis was investigated by FTIR and CHNS analysis. The structural comparison of TFC, TFNC, and MTFC membranes indicated that the degree of grafting (DG) of the composite thin‐film was 17.2, 27.2, and 46.1%, respectively. The structural modification caused the contact angle of TFC, TFNC, and MTFNC to diminish by 47, 34, and 21°, and their porosity to rise by 37, 67, and 53%, respectively. Improvement of porosity and surface hydrophilicity resulted in flux recovery of 87, 100, and 100% in metronidazole filtration by TFC, TFNC, and MTFNC membranes respectively. AFM analysis reported lower roughness of TFNC and MTFNC compared to TFC roughness, obtained in response to less fouling for TFNC and MTFNC over TFC. The size of pores of TFC, TFNC, and MTFNC membranes was measured as 26.5, 16.8, and 14.5 nm respectively, bringing about metronidazole separations of 86.3%, 87.5%, and 98.3%, respectively.

Bionic-inspired La–Zn(4,4′-dipy)(OAc)2/bacterial cellulose composite membrane for efficient separation of nitrogen and phosphorus in water

Phosphorus and nitrogen flow to water leads to eutrophication and depletion of reserves. Bionic-inspired tannin modification is proposed for preparing a tannin-modified La–Zn(4,4′-dipy)(OAc)2/bacterial cellulose composite membrane for simultaneous adsorption of total phosphorus and ammonia nitrogen in water. Its physical and chemical properties were characterized by XRD, SEM, FT-IR, TGA and other characterization methods. La–Zn(4,4′-dipy)(OAc)2 nanomaterial achieved effective adhesion on the tannin-modified bacterial cellulose membrane. Adsorption experiments showed that the composite membrane could both adsorb total phosphorus and ammonia nitrogen, and adsorption capacity of ammonia nitrogen was better than that of total phosphorus. The maximum adsorption capacities of ammonia nitrogen and total phosphorus were 482.35 mg/g and 374.71 mg/g. In the binary solution, the adsorption capacity of the composite membrane to ammonia nitrogen and total phosphorus decreased, but the adsorption capacity to phosphorus decreased slightly. Results of adsorption experiments showed that the adsorption process of nitrogen and phosphorus by the composite membrane belonged to single-layer adsorption, and the calculation results of the kinetic equation were in accordance with the quasi-second-order, and the adsorption equilibrium of the composite membrane was reached within 360 min. In short, the composite membrane had a better adsorption and separation effect both on ammonia nitrogen and total phosphorus.