Natural Kapok Fiber Research Articles

An eco-friendly kapok fiber-supported liquid microextraction using natural deep eutectic solvent as extractant for convenient biological samples preparations: A proof-of-concept study

The use of natural materials and reagents is crucial for developing environmentally friendly methods. This study proposed an excellent green, convenient, cost-effective and rapid sample preparation method called kapok fiber-supported liquid-phase microextraction using natural deep eutectic solvent (KF-SLME-NADES). Natural kapok fiber and NADES were used as greener alternatives to conventional support medium and extractants. Low-toxic ethanol was employed as the desorption solvent. The extraction process was streamlined in a syringe form, allowing for simple pull-push operations. As a proof of concept, the developed methodology was utilized for extracting antidepressants from 3 mL of diluted biological fluids. The optimized KF-SLME-NADES conditions were obtained by single-factor experiments and Box-Behnken design as follows: 2 mg of kapok fiber, 13 μL of NADES composed of menthol and thymol in an equal molar ratio as the extractant, a sampling solution with a pH of 8.0, a desorption solution of 100 μL of ethanol, and four pull-push cycles for both extraction and elution. The validated method provided good linearity (0.05–5.00 μg/mL, R2 > 0.999) and possessed limits of quantification spanning from 0.025 to 0.048 μg/mL. Satisfied accuracies and precisions were obtained with relative recoveries ranging in 93.3–107.2% and intra- and inter-day RSD(%) being below 7.7%. The method greenness was found to be excellent by assessing five greenness evaluation metrics. The devised KF-SLME-NADES strategy provides a sustainable and effective method for bioanalysis.

Natural kapok fiber as a green and efficient adsorbent for in-syringe solid-phase extraction in the determination of antidepressants in biofluids

Effective antidepressant monitoring is crucial for safe treatment, with liquid chromatography being the primary detection method. Due to the complexity of biofluids, meticulous sample preparation is vital to remove interferences and concentrate analytes. In this study, a novel solid-phase extraction method utilizing unprocessed kapok fiber (KF) as an eco-friendly and efficient sorbent, ingeniously incorporated within an in-syringe device for the extraction of antidepressants from biofluids was introduced. The extraction process displayed several advantages, including simplicity and rapidity (less than 3 min with minimal manual intervention), as well as the potential for automation, which represents significant advancements in sample preparation techniques. The method demonstrated excellent analytical performance when coupled with high-performance liquid chromatography-ultraviolet detection, achieving good linearity (R2 ≥ 0.991), excellent relative recovery (92.6–107.5 %), high precision in intraday and interday analyses (RSDs within 0.8–6.0 % and 1.2–7.9 %, respectively), and good sensitivity with limits of quantification between 5–10 ng/mL. Notably, given the use of a renewable and biodegradable material with KF, and a low-toxicity desorption solvent with ethanol, the developed method stands out for its environmental sustainability, aligning with green analytical chemistry principles. Its application to real biological samples validates its efficacy as a rapid and reliable tool for clinical and forensic monitoring of antidepressants. Moreover, the low cost of this method facilitated by the economical nature of KF and the reusability of syringes further enhances its practicability. This study presents a unique approach by employing natural and renewable KF as adsorbents, thereby eliminating the need for complex material synthesis and making a pioneering contribution to the field of analytical chemistry for drug analysis in complex matrices.

Natural lignocellulosic kapok fiber/MXene constructed hydrogel evaporators for high efficiency solar steam generation

Solar-driven interfacial evaporation (SDIE) is a green and sustainable technique for desalination. Hydrogel composite evaporators have been widely used for SDIE, but it is still challenging for the hydrogel evaporators to achieve uniform distribution of the light absorbing nanomaterials and at the same time possess satisfactory evaporation rate, durability and environmental applicability. We developed a 3D hydrogel evaporator with an asymmetric structure for high-efficiency SDIE. Natural kapok fibers, an important lignocellulosic plant fiber with a hollow structure, are decorated with MXene nanosheets for construction of one-dimensional photothermal conversion network. The top composite hydrogel serves as the light-absorption layer where MXene-modified kapok fibers are evenly dispersed in PVA hydrogel, while the bottom PVA hydrogel with an oriented structure acts as water delivery path. The evaporator exhibits a high solar evaporation rate and efficiency (2.49 kg·m−2·h−1 and 91.5 %, respectively) under one sun irradiation (1 kW·m−2). Even in a high salinity brine, emulsion and corrosive solutions, the evaporator can work normally with a slightly decreased evaporation rate. The 3D hydrogel evaporator with long-term stability and durability shows promising applications in purification of seawater and different waste water.

Artemisia argyi essential oil as a green extraction solvent for in-syringe kapok fiber-supported liquid-phase microextraction and determination of triazole fungicide residues

In this study, Artemisia argyi essential oil (AAEO), extracted from the leaves of Artemisia argyi, was employed as a green extraction solvent for in-syringe kapok fiber-supported liquid-phase microextraction (KF-SLME) of hydrophobic compounds in aqueous samples. The wheat of natural kapok fiber as the support medium was 2 mg, and the optimum volume of the extraction solvent AAEO was 12.5 μL. The volume of green desorption solvent 75 % ethanol was 100 μL, which realized a highly environmentally friendly sample preparation method. By simply pulling and pushing the syringe plunger five times, the extraction process enabled rapid and convenient enrichment of analytes while removing most interferences. Coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS), the AAEO-based in-syringe SLME method was applied as a proof-of-concept study to determine triazole fungicides (TFs) residues in fruit juices, herbal oral liquids and herbal extract granules. Employing in-syringe KF-SLME prior to LC-MS/MS detection significantly reduced the limits of quantification (LOQs) by 5–50-fold. The integrated AAEO-based in-syringe KF-SLME-LC-MS/MS method demonstrated satisfactory linearity (R2 ≥ 0.995), accuracies (86.5 %–115.1 %), and precisions (1.2 %–12.7 %) using an isotope calibration method. Furthermore, three greenness assessment metrics uniformly highlighted its outstanding environmental friendliness. The proposed method offers competitive advantages in terms of its environmentally friendly approach, detection sensitivity, analysis cost, and operational convenience.

In-pipette-tip kapok fiber-supported liquid extraction/in-situ derivatization coupled with high-performance liquid chromatography for conveniently determining three furfurals.

This study presents an in-pipette-tip kapok fiber-supported liquid extraction/in-situ derivatization (in-pipette-tip KF-SLE-ISD) method for simultaneous enrichment and derivatization of furfurals. Briefly, 3mg of natural kapok fiber, which was loaded in an assembled pipette-tip, was used to support 12.5μL of extractant (ethyl acetate/toluene, 75:25, v/v) containing 10mM 2,4-dinitrophenylhydrazine. The in-pipette-tip KF-SLE-ISD procedure was conveniently conducted by aspirating/releasing 1mL of sample solution 10 cycles, allowing simultaneous extraction and derivatization of furfurals. Then, 100μL of acetonitrile was aspirated/released 5 cycles for elution, 10μL of which was directly analyzed by high-performance liquid chromatography. The limits of quantitation were in ranges of 0.10-0.45μg/mL. The method showed satisfied linearity (R2>0.99), precision (RSD<8.53%) and relative recovery (90.34-114.71%), which was successfully applied to determine furfurals in various samples (e.g., honeys, juices and glucose injections). The proposed method has the merits of effectiveness, simplicity, low cost, wide availability and ease of automation.

Coupling in-syringe kapok fiber-supported liquid-phase microextraction with flow injection-mass spectrometry for rapid and green biofluid analysis: Determination of antidepressants as an example

Quantification of substances in biofluid samples (e.g., urine, blood, and cerebrospinal fluids) are useful for clinical diagnosis. In current study, a rapid and green strategy by coupling in-syringe kapok fiber-supported liquid-phase microextraction with flow-injection mass spectrometry was proposed. The natural kapok fiber was used as an oily extraction solvent (e.g., n-octanol) support material, and an in-syringe extraction device was conveniently constructed. The whole extraction processes, including sampling, washing and desorption, were conveniently conducted by simply pulling/pushing the syringe plunger, enabling rapid analyte enrichment and sample purification. The follow-up flow injection-mass spectrometry detection enabled rapid and high throughput analysis. As an example, the proposed method was applied to analyze antidepressants in plasma/urine, showing satisfied linearities (R2 ≥0.993) in ranges of 0.2–1000 ng/mL. By employing the in-syringe extraction method prior to flow injection-mass spectrometry detection, the LOQs in plasma and urine were reduced by 25–80 folds and 5–25 folds, respectively. Besides, by employing ethanol and 80% ethanol as the desorption solvent and carrier solvent, respectively, the analytical method showed excellent greenness. In general, the integrated method provides a promising choice for rapid and green biofluid analysis.

Green tubular micro/nano architecture constructed by in-situ planting of small AgNPs on Kapok fiber for oil spill recovery, smart oil–water separation and multifunctional applications

The ubiquitous existence of harmful contaminants in water is recognized as a major threat to aquatic ecosystems and human health, and renewable, economical, and superefficient new materials are needed to eliminate these dangers. Here, the ultrasmall silver nanoparticles (AgNPs) anchored Kapok fiber (KF) (KF/AgNPs) composite capable of efficiently separating various oil–water systems and eliminating other pollutants or bacteria was prepared by a green self-reducing reaction process using natural KF as the “microreactor” and water as the only solvent. The introduction of AgNPs endows KF/AgNPs with significantly improved liquid storage capacity, underwater superoleophobicity and underoil superhydrophobicity, so it shows excellent switchable oil–water separation capability. The oil–water separation efficiencies under gravity reached 99.90 % for the oil-in-water (O/W) emulsion (water flux: 1300 L·m−2·h−1), 99.91 % for the water-in-oil (W/O) emulsion (oil flux: 1500 L·m−2·h−1), and 99.80 % for the immiscible oil–water mixture (flux: 1900 L·m−2·h−1). In addition, KF/AgNPs composite can serve as absorbents to remove oil slicks from sewage (removal efficiency: 99.95 %; absorption capacity: 42.3 g/g) and adsorbents to rapidly remove microplastics in actual natural waters (concentration: 10 mg/L and can inhibit the growth of E. coli bacteria. After use, approximately 96.4 % of Ag was recovered from spent composite, and an excellent biochar adsorbent for the dye was obtained simultaneously.

Kapok fiber derived biochar as an efficient electro-catalyst for H2O2 in-situ generation in an electro-Fenton system for sulfamethoxazole degradation

Developing highly efficient, low-cost, and environmental-friendly catalysts to generate hydrogen peroxide (H2O2) through two-electron oxygen reduction reaction (2e−–ORR) is very important for the electro-Fenton systems. In this work, nitrogen (N) self-doped biochar were synthesized through the carbonization of natural Kapok fiber (KF), and they were used as 2e−–ORR catalysts to generate H2O2 in electro-Fenton systems. The KF-derived biochar that carbonized at 700 °C (named as KFBC-700) exhibited the optimal 2e−–ORR catalytic performance. The pyridinic-N and COOH played key roles on O2 adsorption and reduction. The maximum H2O2 accumulated concentration of the KFBC-700 electro-Fenton system was as high as 108.5 mg/L. Sulfamethoxazole (SMX) can be completely removed through both the Fe2+ catalyzed homogeneous and the FeOCl mediated heterogeneous electron-Fenton reactions within 60 min. Moreover, the electro-Fenton systems showed an excellent stability and reusability for SMX degradation. Additionally, SMX was possibly degraded through three pathways according to the detected degradation intermediates. This paper for the first time used KF-derived biochar as 2e−-ORR catalysts of the electro-Fenton system, and obtained a prominent H2O2 in-situ generation efficiency and a high efficient SMX removal.

Miniaturized kapok fiber-supported liquid extraction for convenient extraction of pesticide residues in vegetable oils: Determination of organochlorine pesticides as a proof-of-concept study

In this paper, a miniaturized kapok fiber-supported liquid extraction (mini-KF-SLE) method was proposed for selective extraction of pesticide residues in vegetable oils. The natural kapok fiber was used as an inert oil support material based on its hydrophobic and lipophilic properties, and the extraction device was conveniently constructed by loading 15 mg of kapok fiber at the lower middle part of a 1-mL pipette tip. The vegetable oil sample (150 mg) without any pretreatment was directly loaded, followed by the addition of 150 μL of acetonitrile (ACN) as the extractant. After static extraction for 30 min, the extractant was pipetted out with a pipettor. As the proof of concept, it was applied for extracting eight organochlorine pesticides (OCPs) from vegetable oils and the eluate was analyzed by gas chromatography-electron capture detector (GC-ECD). Under optimized conditions, the extraction recoveries of OCPs were calculated to be in ranges of 35.8–79.5%. The satisfied quantitation ability was verified by the established method with coefficients of determination (R2) being greater than 0.99. The limits of detection (LODs) were in ranges of 2.0–50.0 ng/g. The relative recoveries were in ranges of 78.3–117.0% with the inter-/intra-day relative standard deviation (RSD) both being less than 13.3%. The potential of mini-KF-SLE to extract other kinds of pesticides was further verified by the successful extracting three triazole pesticides in vegetable oils with good extraction recoveries (>41.4%). The proposed mini-KF-SLE in combination with instrument detection techniques has the great potential in the low-cost and high-throughput determination of various pesticide residues in vegetable oils.

Kapok fiber-supported liquid extraction for convenient oil samples preparations: A feasibility and proof-of-concept study

In this study, a novel kapok fiber-supported liquid extraction (KF-SLE) method was developed for conveniently extracting analytes from oil samples. Natural kapok fiber without any pretreatment was directly used as an oil support medium. The extraction device was conveniently constructed by directly packing some kapok fibers into a syringe tube. Due to the fibrous property of the kapok fiber, no filter plate was needed. The cost of a KF-SLE device was as low as 0.5 CNY. The KF-SLE process was conveniently conducted using a simple three-step protocol: (1) the oil sample without any pretreatment including dilution was added directedly; (2) then, the oil-immiscible extractant was added; (3) after waiting a certain time for static extraction, the extractant was eluted out by pressing the kapok fibers with the syringe plunger. The extractant could be directly transferred for subsequent instrumental detection. For the feasibility and proof-of-concept study, the method was applied to quantify four synthetic flavor chemicals in edible oils. Satisfied quantification results were obtained with the correlation coefficient (R2) being greater than 0.996, the relative recoveries ranging from 92.90% to 107.53% and intra- and inter-day RSDs being less than 7.56%. All in all, for the first time, the SLE technique was expanded to process oil samples and the method has the characteristics of low cost, environmental friendliness, high sample processing throughput and ease of automation, offering a promising approach for edible oil sample preparations.

An intelligent natural fibrous membrane anchored with ZnO for switchable oil/water separation and water purification

Materials with superwettability have attracted much research interest over the last few decades in the field of water-oil separation. Distinct from other superwetting materials, dual superlyophobic materials that have superoleophobicity in water and superhydrophobicity in oil can perform on-demand oil/water separation without requiring extra energy. However, obtaining such a dual superlyophobic membrane with multifunctionality for application in a complicated wastewater environment remains a challenge. Taking advantage of both ZnO and polydopamine, a multifunctional PDA/SC/KFs@ZnO freestanding membrane was prepared in our study. This novel material displays dual superlyophobicity and has potential application for rapid and simultaneous separation of light and heavy oil-water mixtures, oil-in-water emulsions with soluble dye, and water-in-oil emulsions, as well as a good adsorption-catalysis performance for removing soluble dyes in water under visible light. Our work presents a facial and economic method that uses natural kapok fibers to fabricate a special multifunctional superwetting membrane that is promising for future applications.

Zeolite-fiber membrane enabling low-temperature combustion and high reduction of liquid wastes

Adsorbent-containing kapok fiber membranes with high burning rates were developed to remove radionuclides and toxicants from liquid wastes and reduce the total waste volume. The zeolite-fiber membranes were made from natural kapok fibers without allowing the formation of physical or chemical bonds with the zeolite powder. The desorption rate of the adsorbent powder was measured to be within 5% in the aqueous solution for four types of adsorbents with various micro sizes. The adsorption rate of non-radioactive cesium ions with and without the fiber membrane was measured to confirm the effect of the fiber membrane on the adsorption capacity of the adsorbent. Finally, the adsorbent-containing membranes were burned with a volume reduction of 82 wt% without volatilizing the adsorbed cesium at 300 °C.

Bioinspired zeolitic imidazolate framework (ZIF-8) magnetic micromotors for highly efficient removal of organic pollutants from water

This paper reports the first proof-of-concept of using bioinspired ZIF-8 based micromotors for efficient water remediation. Natural kapok fibers have unique hollow structure that contains cellulose and lignin, inspiring the design and fabrication of bubble-driving tubular micromotors as an active self-propelled micromachine for the removal of organic pollutants from water. The outer dense ZIF-8 layer can adsorb organic pollutants on the micromotors, and the inner catalyst acts as the engine decomposing fuel H2O2 for providing bubble propulsion. The magnetic γ-Fe2O3 enables the external magnetic control movement and recovery of micromotors. The maximum adsorption capacity of ZIF-8-based magnetic micromotors toward Congo red and doxycycline were high as 394 and 242 mg g−1, respectively, mainly due to the enhanced micromotor-pollutant contacts by their autonomous motion and the resulting mixing associated effect. This novel ZIF-8 micromotor also showed outstanding stability and reusability in aqueous solution, indicating that their great potential for future application in water treatment.

Fabrication of three-dimensional microtubular kapok fiber carbon aerogel/RuO2 composites for supercapacitors

We prepared carbon aerogel/RuO2 composites with three-dimensional microtubes based on renewable natural kapok fibers by combining a NaClO2 pretreatment, CO2 activation and loading of RuO2 nanoparticles. The electrochemical performance of the material was optimized by tuning the carbonization temperature. The composite calcined at 800 °C for 2 h and activated by CO2 for 30 min possessed an integrated tubular structure and moderate pore size distribution. This composite material also showed highest specific capacitance of 433 F g−1 at a current density of 1 A g−1 with a capacitance retention of 91.5% for 2000 cycles in 3 M KOH solution in three-electrode system. The maximum energy density was 8.92 Wh kg−1 at 558.12 W kg−1 at a cell voltage of 1 V in 3.0 M KOH aqueous electrolyte in a symmetric device. We attribute the reversible capacity of the obtained bio-derived carbon aerogel/RuO2 composites to the high-speed flow of the electrolyte in the unique hollow tubular structure, the appropriate pore size distribution and the synergetic effect of the high capacitance of RuO2 and good stability of the carbon material.

In situ synthesis of open hollow tubular MnO/C with high performance anode materials for lithium ion batteries using kapok fiber as carbon matrix

MnO/C materials with a long lifetime and high rate performance via a biomass template strategy for the lithium ion battery (LIB) market are indispensable. Therefore, novel and efficient ways for their synthesis are urgently required to greatly alleviate the pressure of consuming nonrenewable resources. Herein, we fabricate an open hollow tubular MnO/C hybrid based on the transformation of a natural kapok fiber by hydrothermal and thermal treatment. The as-prepared hybrid material was obtained with high synthesis efficiency and exhibited an extremely stable structure attributed to the in situ growth strategy, overcoming volumetric expansion and self-aggregation of MnO. As an anode material for LIBs, this typical MnO/C electrode demonstrated a high reversible capacity of 1917 mAh · g–1 at 300 mA · g–1 and an excellent rate performance of 693.1 mAh · g–1 at 5000 mA · g–1. More importantly, this biomass carbon-based material demonstrates a superior cycling stability of 1433.1 mAh · g–1 at a high current density of 5000 mA · g–1 after 1000 cycles. The significant electrical performance of this new type of green material is promising for the development of LIBs.

Easy synthesis of TiO2 hollow fibers using kapok as a biotemplate for photocatalytic degradation of the herbicide paraquat

Titanium dioxide (TiO2) hollow fibers (THFs) were synthesized via a template replication method using natural kapok fiber as a biotemplate. The kapok fibers coated with Ti precursor were calcined at temperatures ranging from 450 °C to 750 °C, resulting in the removal of the kapok template and formation of a hollow structure. Based on the characterization results, calcination temperature played a crucial role in altering the THF crystal structure, surface area, and functional group. Photocatalytic activity of THFs was evaluated by investigating the degradation of the herbicide paraquat under ultraviolet (UV) light. The correlation between physicochemical properties and photocatalytic activity of THFs calcined at different temperatures was investigated and discussed in detail.

Bio-template synthesis of three-dimensional microtubular nickel-cobalt layered double hydroxide composites for energy storage

Three-dimensional hollow microtubular nickel-cobalt layered double hydroxide composites were facilely fabricated by controlling the growth on the external and internal surface of natural kapok fibers. The incorporation of kapok fibers induced the confined growth of nickel-cobalt layered double hydroxide on the kapok fiber templates, and the tubular structure of the composite did not collapse with the extension of the hydrothermal time. The obtained unique structure was in favor of enhancing the electrochemical properties of nickel-cobalt hydroxide. The composites prepared after reaction for 8 h exhibited the maximum specific capacity of 1112.25 C g−1 at current density of 0.5 A g−1. Coupled with the active carbon negative electrode, the assembled hybrid supercapacitor device delivered a maximum energy density of 38.0 W h kg−1 with an operational voltage of 1.6 V.

Three-dimensional hollow microtubular carbonized kapok fiber/cobalt-nickel binary oxide composites for high-performance electrode materials of supercapacitors

Three-dimensional hollow microtubular carbonized kapok fiber/cobalt-nickel binary oxide hybrid composites were successfully prepared based on the low-cost natural kapok fiber by combining a simple hydrothermal technique and calcination method. The three-dimensional hollow tubular structure was kept well during the preparation process. The surface morphologies of the as-prepared three-dimensional carbonized kapok fiber/cobalt-nickel binary oxide hybrids changed from the cross-linked fibrous network to the nanoflakes with the increase in the calcination temperature. The composites prepared at 600°C for 2h exhibited a high specific capacity with 502.4Cg−1 at discharge currents of 0.25Ag−1 in 6.0M KOH, and the capacity retention was still maintained at 97.5% after 5000 cycles demonstrating good electrochemical stability. In addition, a hybrid supercapacitor device was also assembled using active carbon and the as-prepared composite as negative and positive electrodes, respectively. It could be operated within a wide potential window of 0.0–1.6V with a high specific energy of 23.2Whkg−1. In addition, the hybrid supercapacitor also exhibited excellent rate capability as well as long-term stability after 5000 cycles. The high reversible capacity of the obtained electroactive hybrid composites can be ascribed to the unique hollow tubular structure, the large surface area, the high defective carbon matrix and the synergetic effect of hybrid electroactive components. Therefore, the as-prepared three-dimensional hollow microtubular hybrids are expected to develop high-performance supercapacitor.

Natural cellulose fiber derived hollow-tubular-oriented polydopamine: In-situ formation of Ag nanoparticles for reduction of 4-nitrophenol

A facile method was reported to achieve hollow-tubular-oriented polydopamine (HTO-PDA) layer using natural kapok fiber (KF) as the bio-template without any pretreatments by altering hydrophobic fiber into hydrophilic one. Subsequently, the HTO-PDA can be utilized for direct in-situ deposition of Ag nanoparticles (NPs). The structures of pristine fiber and HTO-PDA, as well as the resulting Ag NPs attached HTO-PDA (Ag@HTO-PDA) were well characterized by means of scanning electron microscopy (SEM) coupled energy dispersion spectrum (EDS), x-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and Fourier transform infrared (FTIR) spectroscopy. Due to the presence of relatively uniform Ag NPs attached onto PDA layer, Ag@KF-HTO-PDA shows stable catalytic ability towards the reduction of 4-nitrophenol into its amino derivative. Further, this method was used for facile fabrication of Calotropis gigantea fiber derived, surface-functionalized material. The experimental data demonstrated also its excellent catalytic efficiency towards 4-nitrophenol reduction.

Oriented Functionalization of Natural Hollow Kapok Fiber for Highly Efficient Removal of Toxic Hg(II) from Aqueous Solution

Due to hollow and tubular structure, a natural kapok fiber (KF) was used as the support and orientation matrix to control the polymerization of ethyleneglycol dimethacrylate (EGDMA) and N-vinylimidazole (VIM) along its inherent axial surface via a facile in situ rapid polymerization reaction in air atmosphere. The as-formed KF@VIM/EGDMA composite is featured with porous surface and rich N-containing functional groups for potential application as a highly efficient adsorbent for removal of toxic Hg(II) from aqueous solution. The variables affecting the adsorption capacity were studied, including monomer ratio, external pH values, contact time, and initial Hg(II) concentration. The pseudo-second-order equation and two adsorption isotherms including Langmuir and Freundlich equations were applied to determine the adsorption kinetics and adsorption capacity. The results show that the as-prepared KF@VIM/EGDMA composite has a maximum adsorption capacity of 697 mg/g to Hg(II), while no appreciable adsorption capacity can be found for KF itself. Given its intrinsic large lumen, faster adsorption kinetics (45 min) are also expected and observed for KF@VIM/EGDMA. After a simple filtration, this adsorbent can be directly separated from the aqueous solution and then be regenerated for multi-cyclable utilization. During the adsorption process, the chemical complexing represents the main adsorption mechanism. As a naturally renewable KF, such a simple preparation method opens a new avenue to develop highly efficient and economically viable adsorbent for removal of toxic heavy metal from aqueous solution.