Chemical Adsorption Mechanism Research Articles

Mercury(II) decontamination using a newly synthesized poly(acrylonitrile-acrylic acid)/ammonium molybdophosphate composite exchanger

Mercury is a high priority pollutant because of its fatal effects on the ecosystem. This manuscript demonstrates the preparation of a new organic-inorganic composite exchanger resin for the removal of divalent mercury (Hg(II)) by adsorption from aqueous solution. The preparation was based on binding polymer poly(acrylonitrile-acrylic acid) [P(AN-AA)] with ammonium molybdophosphate (AMP). The prepared adsorbents (P(AN-AA)/AMP and P(AN-AA)) were characterized using FTIR, SEM, BET, and TGA for assigning their physicochemical properties. The conditions controlling the adsorption process were optimized. The removal by P(AN-AA)/AMP and P(AN-AA) reached 96.5 and 77.5%, respectively. The isotherm and kinetics studies showed that the experimental results fit well with the Langmuir isotherm model and the pseudo-second-order kinetic model with a maximum adsorption capacity of 221.23 and 202.43 mg/g for P(AN-AA)/AMP and P(AN-AA), respectively. The thermodynamic study showed that the adsorption process is endothermic in nature with an enthalpy of 88.38 and 9.33 kJ/mol for P(AN-AA)/AMP and P(AN-AA), respectively. The obtained results suggest that strong chemical adsorption mechanism highly participated in the adsorption process.

Experimental and computational investigations of a novel quinoline derivative as a corrosion inhibitor for mild steel in salty water

The inhibition efficiency of N- and/or O-containing compounds for the corrosion of metals and alloys in aggressive media is an essential theme. For this purpose, a newly synthesized and fully characterized multidentate ligand, N,N'-((ethane-1,2-diylbis(azanediyl))bis(ethane-2,1-diyl))bis(quinoline-2-carboxamide) (QATETA), derived from quinaldic acid and triethylenetetramine (TETA) was examined gravimetrically and electrochemically as an inhibitor for the corrosion for mild steel in aqueous sodium chloride (3.5 %). Moreover, the reactivity and efficiency of QATETA were also theoretically investigated using density functional theory and Monte Carlo simulations methods. The results indicate that the corrosion inhibition of QATETA was concentration-dependent. In addition, QATETA was categorized as a mixed type inhibitor. Thermodynamic calculations confirmed that the adsorption of QATETA on the metal surface is a spontaneous process obeying Langmuir adsorption isotherm. Furthermore, computational simulations have corroborated the experimental results. Both physical and chemical adsorption mechanisms are suggested.

Synthesis of bio-based nickel nanoparticles composite, characterization and corrosion in hibition in simulated oilfield microbial and acidizing environments

Aqueous extract of Citrus reticulata peels (CRE) mediated synthesis of nickel nanoparticles (CRE-NiNPs), characterization and application of the obtained composite as microbial and acid corrosion inhibitor is reported. The CRE-NiNPs were stable, non-agglomerated, monodispersed, round-shaped and of 40 − 55 nm size. With surfaces rich in O and N sites, CRE-NiNPs efficiently adsorbs on and inhibits X80 steel corrosion in I M HCl solution with efficiency of 87.3% and 80.6% at 30 and 60 °C, respectively. The nanoparticle also affords 3-log reduction in Desulfovibrio sp population and 73.2% inhibition efficiency at 3.21 mg/L minimum inhibitory concentration. Potentiation with D-tyrosine increases the efficiency to 79.7% and 5-log reduction in microbial population. Microbial corrosion inhibition is attributed to ease of penetration through bacteria cells to subdue their metabolic via physical and chemical adsorption mechanisms. Compared to the crude, CRE-NiNPs is more thermally stable, more efficient and affords better surface protection at high temperature. Highlights Citrus reticulata peels extract (CRE) mediated nickel nanoparticles (CRE-Ni NPs) were synthesized and characterized. CRE-Ni NPs richer in N and O sites, more stable and efficiently inhibits corrosion at high temperatures than CRE Small size enhances high efficiency against Desulfovibrio sp with over 3-log population reduction Adsorption of CRE-Ni NPs is by combined physisorption and chemisorption enabled by C=C, C=O, C–O, O–H and N–H sites

Mercury removal by porous sulfur copolymers: Adsorption isotherm and kinetics studies

Mercury is one of the most toxic, harmful element present in water that severely affects human health. Many traditional as well as advanced technologies were developed to remove mercury from wastewater. In this study, sulfur copolymers containing micro and macro porous structure were prepared via inverse vulcanization technique and used to capture the mercury ions from wastewater. Initially, porogens with varying particle size were added to the sulfur and cross-linker mixture, later the obtained solid copolymers was treated with water to generate porous structure with different porosicity. Structure of the prepared sulfur copolymer was confirmed by FTIR, NMR spectroscopy and the surface morphology studied by SEM indicate the presence porous structure relating to the size of the porogen. Thermal properties analyzed by DSC and TGA supports the stability of the copolymer. Obtained sulfur foams were used to capture mercury ions from water and studied the adsorption behaviour using different isotherm and kinetics models. The adsorption kinetics showed a pseudo-second-order rate equation and the metal ion diffusion was found to be a combination of both intraparticle and liquid film diffusion mechanisms. The adsorption capacity improved with the increasing porosity in the sulfur foam and the adsorption isotherm suggested that the mercury ions were captured via both physical and chemical adsorption mechanism. Modification in the sulfur foam porosity can significantly influence the mercury ion adsorption capacity. The main advantage of this technique is the use of surplus sulfur and one step preparation method which can be scalable and cost effective.

Evaluation of some amino benzoic acid and 4-aminoantipyrine derived Schiff bases as corrosion inhibitors for mild steel in acidic medium: Synthesis, experimental and computational studies

The corrosion inhibition of steel in 1 M HCl in the presence of four synthesized Schiff bases: 3-[(3-Hydroxy-4-methoxy-benzylidene)-amino]-benzoic acid (HMAMB), 3-[(2-Hydroxy-naphthalen-1-ylmethylene)-amino]-benzoic acid (HNCAMB), 3-[3-(4-Methoxy-phenyl)-allylideneamino]-benzoic acid (TMCAMB) and 4-[3-(4-Methoxy-phenyl)-allylideneamino]-1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazol-3-one (TMCATP) was studied by potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), surface analyses and computational studies. The inhibition efficiency of HMAMB, HNCAMB, TMCAMB and TMCATP obtained at the optimum inhibitor concentration (1.0 mM) from polarization measurement were 87.3%, 89.1%, 96.5% and 97.0% respectively. The values of inhibition efficiencies obtained via the electrochemical analyses for the four inhibitors were comparable. The data from polarization measurement implies the compounds inhibited as mixed-type inhibiting molecules in the tested media but mostly minimized the cathodic reaction. The data obtained experimentally fitted well into Langmuir adsorption isotherm with R2 values and slopes close to unity. The values of Gibbs free energy of adsorption ranged from −33.96 to −37.62 kJ mol−1, suggesting that the molecules adsorbed spontaneously to the surface of the metal by interchange of physical and chemical adsorption mechanisms. The energy dispersive X-ray (EDX) spectra results displayed a decrease in the percentage of oxygen on the surface of the mild steel and scanning electron microscopy (SEM) micrograph also indicated a minimal damage of the metal surface in solutions containing the Schiff bases when likened to the solution without the inhibitors. The results of DFT calculations showed that the molecules had high tendencies in interacting with the steel surface. The values of energy gap (eV) obtained were 4.09, 3.74, 3.69 and 3.58 while the estimated adsorption energy obtained from molecular dynamic simulation studies were − 654.2, −760.8, −741.3 and − 951.9 kJ mol−1 for HMAMB, HNCAMB, TMCAMB and TMCATP, respectively.

Synthesis, characterization and application of mesoporous silica in removal of cobalt ions from contaminated water

Mesoporous silica was synthesized by a chemical precipitation process and its efficiency was investigated for removal of cobalt ions (Co2+) from the contaminated water in a laboratory scale. The characteristic of the synthesized mesoporous were analyzed by SEM image. Optimal conditions were determined for important parameters such as solution pH, the absorbent dose, the initial Co2+ concentration and contact time by a one-variable method through the batch experiments. The SEM results confirmed the synthesized silica had high porosity with a honeycomb-like structure. The results showed that increase the adsorbent dose and contact time to the optimum increased the efficiency of Co2+ adsorption. However, with increasing the concentration of Co2+, the removal efficiency was decreased. The removal of Co2+ was 85% at the optimal contact time of 8 h. The maximum adsorption efficiency was 89% at pH = 7, initial Co2+ concentration of 5 ppm, and the adsorbent dose of 0.3 g/50 ml. The study of adsorption isotherm and kinetic models indicated that the adsorption process followed the Freundlich isotherm (R2 = 0.9359) and the second-order kinetic model (R2 = 0.9995). The synthesized mesoporous silica presented a chemical adsorption mechanism for Co2+ removal from aqueous media and it can be used in wastewater treatment containing bivalent heavy metals such as Co2+.

Polyaniline/sulfonated‐covalent organic polymer nanocomposite: Structural and dye adsorption properties

AbstractThe aim of this work is developing an adsorbent for the removal of anionic Acid Blue 45 dye from aqueous solutions. In this regard, the polyaniline/sulfonated‐covalent organic polymer nanocomposites (PANI/S‐COP NCs) were synthesized by in situ chemical polymerization method. The structure and morphology of these prepared nanocomposites were characterized by different techniques. The structural stability of the synthesized adsorbent was examined under different pH conditions. To optimize the adsorption conditions, various parameters such as pH, dye concentration, adsorbent dosage, contact time, and temperature were investigated. The maximum adsorption capacity of the prepared composite for 100 ppm of dye (at 25.0°C, pH: 5, and time: 120 minutes as optimum conditions) was 117 mg g−1. Different adsorption models were applied for the fitting of the obtained experimental data. It was found that the adsorption data can be well fitted to the linear Langmuir model (R2: .999). The adsorption kinetics can also be well described by the linear pseudo‐second‐order model, indicating the chemical adsorption mechanism for the dye molecules on the PANI/S‐COP NCs surface.

Adsorption and Removal Characterization of Nitrobenzene by Graphene Oxide Coated by Polythiophene Nanoparticles

Nitrobenzene (NB) has a wide range of usages as a chemical intermediate and also as a dye in printing applications. Despite its advantages, NB is harmful to human and animals and hence is an environmental pollutant. In this research, NB removal from water was studied via adsorption on graphene oxide (GO) coated by polythiophene (PT) nanoparticles. The resulting nanocomposite was characterized by XRD, FTIR, BET, and SEM. While the FTIR tests proved successful incorporation of PT, the SEM images displayed a relatively larger surface area compared to other studies. The BET analysis confirms this finding by reporting the surface area as 917.8 m2/g for the adsorbent. The adsorption mechanism was assessed by the Langmuir and Freundlich isotherms. The results show that the Freundlich isotherm better describes the adsorption process compared to the Langmuir isotherm. On the other hand, the pseudo-second-order kinetic model better regresses the experimental results, which indicates a chemical adsorption mechanism. The adsorption-desorption behavior of the samples was evaluated at optimized pH, time, adsorbent dosage, and eluent type. The results showed that the synthesized nanocomposite can efficiently remove NB from solutions in the pH range of 5.0 to 7.0, with the maximum adsorption capacity of 15.6 mg/g.

Freeze-thaw as a route to build manageable polysaccharide cryogel for deep cleaning of crystal violet

Crystal violet (CV) is one of the most toxic organic dyes, thus there is a critical need to remove it from wastewater before discharging into the environment. To tackle this challenge, new resources should be exploited to construct green and environmentally friendly adsorbents. Herein, we designed a novel cryogel by freeze-thaw of naturally derived polysaccharides salecan and locust bean gum (LBG) without any toxic and organic cross-linkers. Their three-dimensional network structure was established by strong hydrogen bonding interactions between the two polysaccharides and has been characterized systematically. More specially, salecan/LBG ratio could be accurately tuned to enhance the storage modulus, and to adjust the hydrophilicity and pore architecture of these cryogels. Batch experiments with the subject of salecan/LBG ratios, pHs, initial dye concentrations as well as contact time were studied. The adsorption equilibrium data could be well-fitted with pseudo-second-order model and Langmuir model, revealing monolayer chemical adsorption mechanism. The maximum CV adsorption capacity calculated by Langmuir equation was 309.5 mg/g, higher than many reported CV adsorbents. Notably, the regenerated cryogel could be easily reused with high adsorption capacity for at least five cycles. This work provided a facile avenue to develop sustainable cryogel adsorbent for deep cleaning of CV in wastewater.

Co-doped ZnS with large adsorption capacity for recovering Hg0 from non-ferrous metal smelting gas as a co-benefit of electrostatic demisters.

The installation of electrostatic demisters (ESDs) makes possible the use of sorbent injection technology for recovering Hg0 from non-ferrous smelting gas. ZnS, as a typical smelting raw material, could be a promising candidate due to the sulfur boding site for mercury. However, the low reaction rate and poor adsorption capacity limited its application. In this study, Co was incorporated into ZnS to enhance adsorption activity for recovering Hg0. Co0.2Zn0.8S exhibited the best Hg0 capture performance among the modified sorbents. The Hg0 adsorption capacity was up to 46.01mg/g at 50°C (with 50% breakthrough threshold), and the adsorption rate was as high as 0.017mg/(gmin). Meanwhile, SO2 and H2O had no poison effects on Hg0 adsorption. The chemical adsorption mechanism was proposed, which was Co3+, and sulfur active sites could immobilize Hg0 in the form of stable HgS, following a Mars-Maessen reaction pathway. The spent sorbent will release ultrahigh concentration mercury-containing vapor through the heating treatment, which facilitated centralized recovery of Hg0. Meanwhile, inactivated sorbent can be used as smelting raw material to recover sulfur resources. Therefore, the control of Hg0 emission from non-ferrous smelting gas by Co-adopted ZnS was cost-effective and did not form secondary pollution. Graphical abstract.

Antifebrin Drug Prepared via One-Stage Green Method as Sustainable Corrosion Inhibitor for Al in 3 M HCl Medium: Insight from Electrochemical, Gasometric, and Quantum Chemical Studies

The medicinal compound antifebrin was prepared in the laboratory via one stage (green method) by using aniline, glacial acetic acid, and zinc dust. The investigation was aimed at ascertain a possibility of utilizing the medicinal compound to originate a corrosion inhibitor for Al in a 3 M HCl solution. In the present article, the usefulness of antifebrin to inhibit the Al corrosion in 3 M HCl solution was examined by the Tafel plot, AC impedance spectroscopy, gasometric and quantum chemical techniques. The Tafel plot results show that concentration of antifebrin has a positive effect on the inhibition efficiency. The Tafel plot also reveals that this medicinal compound inhibits the acidic corrosion of aluminum by a mixed mode. Impedance spectroscopy results show that corrosion resistance of Al in a 3 M hydrochloric acid was improved by antifebrin. For better understanding the relationship between the antifebrin molecular structure and inhibitory ability, quantum calculations (by using Argus Lab = latest version) were performed. Surface studies were carried out by scanning electron microscopy. The Langmuir plot confirms the chemical adsorption mechanism on the Al surface in a 3 M HCl solution in the presence of antifebrin.

Effective decontamination of As(V), Hg(II), and U(VI) toxic ions from water using novel muscovite/zeolite aluminosilicate composite: adsorption behavior and mechanism.

Muscovite/phillipsitic zeolite was introduced as a novel inorganic composite of stunning adsorption properties. The composite was investigated in the uptake reactions of Hg(II), As(V), and U(VI) as highly toxic water contaminants considering different adsorption factors. The adsorption properties of muscovite/phillipsitic zeolite are highly dependent on the pH values and the best decontamination percentages can be obtained at pH4, pH5, and pH5 for Hg(II), As(V), and U(VI), respectively. The kinetic studies demonstrated adsorption equilibrium for Hg(II), As(V), and U(VI) after 360min, 300min, and 360min, respectively. The equilibrium modeling suggested monolayer uptake for all the metals and represented mainly by the Langmuir model considering both the values of determination coefficient and chi-squared (χ2). The estimated maximum capacities are 117mg/g (Hg(II)), 122.5mg/g (As(V)), and 138.5mg/g (U(VI)) which are higher values than several studied adsorbents. The Dubinin-Radushkevich adsorption energies of Hg(II) (19.4kJ/mol), As(V) (25.6kJ/mol), and U(VI) (26.47kJ/mol) signify chemical adsorption mechanisms and close to the obtained values for the ion-exchange process. Additionally, the composite is of high reusability properties and was applied effectively for five decontamination cycles. Graphical abstract.

Preparation of a Solid Amine Microspherical Adsorbent with High CO2 Adsorption Capacity.

Amine-skeleton solid-amine materials are promising adsorbents for CO2 capture from flue gas. Here, a novel solid-amine microsphere was synthesized by cross-linking the skeleton poly(ethylenimine) (PEI) with ethylene glycol diglycidyl ether in a facile one-pot W/O emulsion system. The material had a remarkable CO2 adsorption capacity of 7.28 mmol/g in the presence of moisture at 20 °C, 0.1 bar. The highest ratio of breakthrough capacity to saturation capacity was ca. 84%. According to kinetic simulation, the Avrami kinetic model could better describe the adsorption process of CO2 under different temperatures, in which the value of R2 was above 0.99 and n was between 1 and 2, indicating that both physical and chemical adsorption mechanisms were performed during adsorption. Moreover, the material had a high swelling speed. Equilibrium was established within 30 s, and the swelling ratio was 271% at equilibrium. The saturated adsorbent could be easily regenerated with a regeneration efficiency of 94.63% after six cycles. The PEI microsphere appears to be a promising candidate material for CO2 capture from flue gas.

Corrosion and Kinetic Study of Eucalyptus camaldulensis Seeds Extract Percolated with Methanol on Aluminium Coupons in HCl

This research discusses a detail optimization of Eucalyptus camaldulensis seeds extract as corrosion inhibitor for aluminum coupons in HCl using weight loss measurement and kinetic study. The result shows that the maximum inhibitor efficiency was obtained at a concentration of 2.0 (%W/V). However the highest inhibitor efficiency of 85% was obtained at 50ºC and the least inhibitor efficiency of 29% was obtained at 30ºC. Thermodynamic consideration revealed that adsorption of inhibitor of aluminum surface was exothermic and consistent with chemical adsorption mechanism.

Synthesis and corrosion inhibition studies of modified polyacrylic acid bearing triazole moieties on aluminium in alkaline medium

Novel modified Polyacrylic acid (ACTP) bearing triazole pendant moieties prepared with polyacrylyl chloride and 3-amino-1,2,4-triazole-5-thiol through polycondensation reaction. The synthesized polymer was characterized using nuclear magnetic resonance (lH-NMR, 13C-NMR), fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive studies (EDAX) and thermogravimetric (TGA) studies. The ACTP polymer was tested as corrosion inhibitor with aluminium metal in alkaline medium and their results were compared with synthesized simple polyacrylic acid (PAA). Gravimetric, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization techniques were used to test the efficiency of the corrosion inhibitor. Activation energy and free energy for inhibition reaction supports both chemical and physical adsorption mechanism, with better inhibition efficiency. Potentiodynamic polarization curves validated that the corrosion inhibitors behave an anodic type.

Corn Straw Residue: a Strategy for Lipase Immobilization.

This work aims to study the immobilization of Candida rugosa lipase (CRL) onto corn straw residue. For this purpose, chemical, morphological, and textural characteristics of the corn straw; immobilization process by adsorption; and immobilized enzyme activity and storage stability were evaluated. The corn straw presented isoelectric point of 7.0, surface with hydroxyl bands being favorable to the immobilization process. An irregular surface was also observed with fibers and pores, which are mesoporous and macroporous, characteristics that demonstrate efficiency in mass transfer mechanisms. Upon immobilization, it was observed that adsorption velocity is proportional to the square of the available adsorption sites (pseudo-second-order), and that the immobilization occurs in monolayers (Langmuir isotherm). The adsorption process was favorable and considered as a chemical adsorption mechanism. After immobilization, the optimum temperature increased, the optimum pH reduced, and the affinity of the biocatalyst for the substrate decreased. Corn straw derivative demonstrated good thermal stability. Regarding storage stability, there was approximately 12% loss of activity after 60 days of storage at 4 °C. Considering that no treatment was applied to the corn straw, this result is satisfactory and shows good affinity between this support and CRL.

Synthesis and Characterization of a Chemically-Activated Novel Mesoporous Silica for Cobalt Decontamination from Polluted Water

Mesoporous silica was synthesized by a chemical process and its efficiency was investigated for removal of cobalt (Co2+) ions from contaminated water in a laboratory scale. The characteristics of synthesized mesoporous were analyzed by SEM/TGA. Optimal conditions were determined for important parameters such as solution pH, the absorbent dose, the initial Co2+ concentration, and contact time by a single-variable method through the batch experiments. The SEM results confirmed the synthesized silica had high porosity with a honeycomb-like structure. The results showed that with an increasing adsorbent dose and contact time to the optimum, the efficiency of Co2+ adsorption increased. However, with increasing concentration of Co2+, the removal efficiency decreased. At optimal contact time (8 h), 85 % of Co2+ was removed. The maximum adsorption efficiency at pH =7, initial Co2+ concentration of 5 ppm, and at the adsorbent dose 0.3 g/50 ml, was 89%. The study of adsorption isotherm and kinetic models showed that the adsorption process followed the Freundlich isotherm (R2 = 0.9359) and the second-order kinetic model (R2=0.999). Therefore, the synthesized mesoporous silica presented a chemical adsorption mechanism for Co2+ removal from aqueous media and can be utilized in wastewater treatment containing divalent heavy metals such as Co2+.

Nano-sized Prussian blue immobilized costless agro-industrial waste for the removal of cesium-137 ions.

For human health and safety, it is of great importance to develop innovative materials with a vast capacity for powerful removal of radioactive ions from aqueous solutions. Prussian blue functionalized sugarcane bagasse (PB-SCB) was successfully prepared for the efficient elimination of radioactive cesium (137Cs) using a nontoxic, environmentally friendly, and costless method. The prepared renewable material was characterized using different techniques to emphasize morphology, functional groups, crystal structure, and the adsorption process. The adsorption of Cs(I) was better fitted to the pseudo-second-order model than pseudo-first-order model which revealed a chemical adsorption mechanism. The experimental isotherm results were best illustrated by the Freundlich model (R2 = 0.98). Besides, the obtained values for the thermodynamic parameters indicating that the adsorption process was endothermic and spontaneous in nature. In addition to demonstrating high adsorption capacity for Cs ion removal (56.7mg/g at 30°C), PB-SCB might consider being an efficient and cost-effective adsorbent for the decontamination of cesium, where an estimated cost analysis revealed that the expenditure for the removal of 1000mg/L cesium from alkaline radioactive wastewater is likely to be US$0.12. Graphical abstract.

Investigation of the Interaction of Water Molecules with the Surface of a Quartz Tube Using Diode Laser Spectroscopy

The behavior of water molecules at the density of 1013 to 1016 cm−3 in a fused silica tube at room temperature has been studied. The number of molecules in the gas phase initially injected in the tube is comparable to the number of molecules adsorbed on the walls of the pre-evacuated tube. The concentrations of molecules in the gas phase were measured by diode laser spectroscopy with an external optical cavity. An off-axis alignment of the cavity with a large set number of transverse modes was used, which made it possible to measure the concentrations of molecules with narrow absorption profiles, temporal resolution of 5 s, and the accuracy better than ±5%. A strong interaction of molecules with the walls was observed. The time behavior of molecules in the gas phase both after the injection of gas into the vacuum volume and after its rapid evacuation under dynamic equilibrium between capture and desorption processes is non-exponential. The characteristic time of these processes 10−11 to 102 s depends on the redistribution of molecules between the gas and the near-wall layers, which is governed by the physical and chemical adsorption mechanisms. The theoretical results on the kinetics of the processes are in good agreement with the experimental data.

Fabrication of polyethylenimine-functionalized sodium alginate/cellulose nanocrystal/polyvinyl alcohol core–shell microspheres ((PVA/SA/CNC)@PEI) for diclofenac sodium adsorption

HypothesisWe synthesized composite microspheres from cellulose nanocrystal (CNC), polyvinyl alcohol (PVA), and sodium alginate (SA), which were modified with polyethyleneimine (PEI) to introduce a high density of active amino sites onto the surface via the Schiff base reaction. We hypothesized that these (SA/CNC/PVA)@PEI microspheres would have a high adsorption capacity for aqueous diclofenac sodium (DS). ExperimentsThe PEI-modified composite microspheres were characterized and assessed and optimized for aqueous DS adsorption. In addition, the morphology and synthesis mechanism of the adsorbent were studied. FindingsThe adsorption process showed a good fit with the pseudo-second-order kinetic model (i.e., the process is driven by a chemical adsorption mechanism) and Langmuir adsorption isotherm model (i.e., adsorption follows a single-layer process). Under the optimum experimental conditions (pH: 4.5, adsorption time: 50 min, temperature: 303 K), the maximum adsorption capacity was 418.4104 mg/g, which was relatively high compared to other reported adsorbents. Importantly, after five adsorption–desorption cycles, (SA/CNC/PVA)@PEI showed only a slight loss in adsorption capacity. Compared with other reported adsorbents, the core–shell composite has a good DS adsorptive capacity and high recyclability.