Adsorbent For Removal Of Dyes Research Articles

On the applicability of triazine-based covalent organic polymer as adsorbent for dye removal from aqueous solution

Triazine-based covalent organic polymer, TCOP, is synthesized via the reaction between cyanuric chloride and piperazine in 1,4-dioxane, and is characterized with FT-IR, EDX, elemental mapping, XRD, SEM, TEM and N2 adsorption/desorption techniques. The capability of TCOP in the removal of different types of dye pollutants is studied and it was found that the removal efficiency is more than 70% for all of them. The kinetics and equilibrium adsorption of Rhodamine B (RhB) was studied at different conditions. Most of the adsorption takes place in less than 20 min and the maximum adsorption capacity is 153 mg/g. The adsorption isotherm can be well described by the modified Langmuir-Freundlich equation and the adsorption kinetics follows the fractal-like pseudo-first order kinetics model. Both of the fitted models reveal the heterogeneity of adsorbent. The adsorption thermodynamics parameters were calculated and interpreted. Finally, it was shown that the prepared TCOP can be used for the removal of dye mixture from aqueous solution.

Thiacalix[4]arene-functionalized magnetic xanthan gum (TC4As-XG@Fe3O4) as a hydrogel adsorbent for removal of dye and pesticide from water medium

A novel thiacalixarene-functionalized biopolymer nanocomposite hydrogel was designed and prepared as an efficient adsorbent system to elimination of aquatic areas from chlorpyrifos (CPF) and crystal violet (CV). This adsorbent system was conducted by multi-step including; preparation of Fe3O4@XG hydrogel through in-situ magnetization of XG, amine modification of Fe3O4@XG hydrogel by using 3-aminopropyltriethoxysilane (APTES) to get Fe3O4@XG-NH2, the synthesis of TC4As supramolecule, its functionalization with epichlorohydrin (ECH) and eventually covalently attachment of ECH-modified TC4As onto as-prepared Fe3O4@XG-NH2 to obtain the TC4As-XG@Fe3O4 nanocomposite hydrogel. Several characterization techniques including FTIR, XRD, FESEM, VSM, TGA, and BET demonstrated the successful synthesis of TC4As-functionalized XG nanocomposite hydrogel. The result of characterization demonstrated that the TC4As-XG@Fe3O4 adsorbent system showed superparamagnetic property with magnetic saturation (Ms) of 9.10 emu/g and high thermal stability with 73 % char yields. The XRD pattern of TC4As-XG@Fe3O4 nanocomposite showed characteristic peaks of Fe3O4 MNPs and XG, but with enhanced crystallinity in compared to neat XG as result of in-situ magnetization of XG as well as its functionalization with TC4As. The BET surface area of Fe3O4@XG and TC4As-XG@Fe3O4 hydrogels was measured approximately 45.32 and 17.30 m2/g, which was higher than neat XG. Then, the constructed adsorbent system was assessed for removing a CPF as an organophosphorus pesticide and CV as cationic dye from aqueous. The batch adsorption experiments were conducted to optimize the effective adsorption parameter i.e., solution pH, adsorbent dosage, contact time, CPF and CV initial concentration. Furthermore, Freundlich isotherm mode was well-fitted model and by utilizing prepared adsorbent, and the maximum adsorption capacities of CPF and CV (at optimum conditions: 298 K, pH 7.0 and 9.0) were found to be about 769.230 and 833.33 mg/g, respectively. The adsorption kinetic study revealed that experimental data were well-fitted by the pseudo-second-order model. Based on proposed mechanism, the CPF and CV were adsorbed onto hydrogel nanocomposite mainly through π–π interactions, electrostatic interaction and hydrogen bonding. The regeneration experiments up to three cycles were best achieved for two studied pollutants.

Efficient extraction of silica from openly burned rice husk ash as adsorbent for dye removal

Rice is the staple food in many countries including Bangladesh. In Bangladesh, >80% of the total irrigated area is planted with rice, which generates a huge amount of rice husk (RH) as a solid waste which requires proper management. This study, therefore, aimed to extract amorphous silica from openly burned rice husk ash (RHA) using a simple method by avoiding calcination or combustion processes. The extracted silica was then applied for the removal of environmental contaminants i.e., methylene blue dye from an aqueous solution. It was found that the yield of silica produced from sulfuric acid-pretreated RHA was 72.4%. The FTIR absorption peaks at 1057 and 783 cm−1 indicate the presence of a highly condensed silica-containing asymmetric and symmetric siloxane (Si–O–Si) network mixture. The broad maximum bond peak intensity at 2θ = 22° by x-ray diffraction analysis also indicates that the produced silica was amorphous with a mesoporous structure. The surface area of sulfuric acid treated RHA-based silica was 183 m2/g. This silica resulted in a maximum adsorption capacity of 107 mg/g of methylene blue at pH 8 with a faster equilibrium reached at 60 min. The mechanistic study indicated that both Langmuir and Freundlich adsorption isotherms were both fitted well which suggested homogeneous adsorbent surfaces involving monolayer and multilayer adsorption processes.

The Synthesis of Metal–Organic-Framework-Based Ternary Nanocomposite for the Adsorption of Organic Dyes from Aqueous Solutions

In the present study, a ternary magnetic nanocomposite (SiO2/MnFe2O4/ZIF-8) was synthesized via the embedding of the SiO2/MnFe2O4 nanocomposite within the metal–organic framework (ZIF-8). The synthesized nanocomposite was characterized using suitable techniques including FT-IR, XRD, SEM, TEM, VSM, and BET. The nanocomposite showed a high surface area (SBET = 831 m2·g−1) and superparamagnetic behavior (23.7 emu·g−1). All characterization techniques confirmed the successful combination of three nanocomposite parts (MnFe2O4, SiO2, and ZIF-8). The nanocomposite was examined for the adsorption of organic dyes, malachite green (MG) and methyl red (MR), from aqueous solutions. The adsorption conditions including ionic strength, contact time, pH, and adsorbent dosage were optimized by studying their change effect. The SiO2/MnFe2O4/ZIF-8 nanocomposite showed high adsorption capacities (1000.03 and 1111.12 mg/g) for the removal of MG and MR, respectively, from water. The isotherm and kinetics studies indicated that the adsorption of MG and MR dyes on the surface of the SiO2/MnFe2O4/ZIF-8 nanocomposite followed the Langmuir isotherm model and pseudo-second-order kinetic model, suggesting the monolayer chemisorption mechanism. The reusability study of up to five successive cycles indicated the successful reuse of the SiO2/MnFe2O4/ZIF-8 adsorbent for dye removal from wastewater. The comparison of the present adsorbent to the previously reported adsorbents indicated that it is a promising adsorbent for dye adsorption from wastewater and must be investigated in the future for the removal of additional pollutants.

Adsorption property and mechanism of forest wastes based naturel adsorbent for removal of dye from aqueous media

Adsorption property and mechanism of forest wastes based naturel adsorbent for removal of dye from aqueous media

Adsorptive removal of dye from textile wastewater employing Moringa oleifera leaves biochar as a natural biosorbent

Adsorptive removal of dye from textile wastewater employing Moringa oleifera leaves biochar as a natural biosorbent

Layered Double Hydroxides as Rising-Star Adsorbents for Water Purification: A Brief Discussion.

Within the frame of this article, briefly but comprehensively, we present the existing knowledge, perspectives, and challenges for the utilization of Layered Double Hydroxides (LDHs) as adsorbents against a plethora of pollutants in aquatic matrixes. The use of LDHs as adsorbents was established by considering their significant physicochemical features, including their textural, structural, morphological, and chemical composition, as well as their method of synthesis, followed by their advantages and disadvantages as remediation media. The utilization of LDHs towards the adsorptive removal of dyes, metals, oxyanions, and emerging pollutants is critically reviewed, while all the reported kinds of interactions that gather the removal are collectively presented. Finally, future perspectives on the topic are discussed. It is expected that this discussion will encourage researchers in the area to seek new ideas for the design, development, and applications of novel LDHs-based nanomaterials as selective adsorbents, and hence to further explore the potential of their utilization also for analytic approaches to detect and monitor various pollutants.

Adsorption of Dyes Using Natural Minerals: A Review

<p>Adsorption is an effective and widely technique used for separation many pollutants from wastewater. Pollution of water with color material such as dyes is of environmental concern due to their toxicity and cause carcinogenic effects on human and aquatic life. These dyes are presented into the water bodies from the effluence of several industries such as textile, paints, cosmetics, paper, food, and others causing water pollution. Adsorption technique using low cost adsorbents has gain a lot of attraction of many researchers for years. The purpose of the present study is to investigate for using natural mineral as inexpensive adsorbents for removal of dyes from wastewater. This investigation can be made by reviewing the major topic researches that applying natural mineral material as cheap adsorbents for treating of colored wastewater. A natural materials such as vermiculite, sepiolite, montmorillonite, kaolinite, perlite, diatomite, zeolite, and others, which are categorized as permeable minerals, multilayer minerals and other based on structure properties. These adsorbents can be used as is or changed to enhance adsorption properties.</p>

Preparation, Modification and Characterization of Chitosan-Oxalic Kola Nut Pod Adsorbent

Abstract: This work investigated the preparation, modification and characterization of prepared adsorbent from kola nut pod (agro waste).The kola nut pod waste was obtained from Ipetu-Ijesha farm, modified using chitosan-oxalic gel and characterized using Scanning Electron micrograph -Energy dispersive X-ray and FTIR spectrophotometer. The morphological study revealed that the chemically modified adsorbent has high porosity and large surface area for effective adsorption of metal ions in aqueous solution, The EDX analysis revealed that the chitosan-oxalic modified kola nut pod adsorbent contains C (0.01%), N (14.46%), K (7.76%), O (14.48%), Si (0.09%) and Ca (62.24%). The FTIR spectrum shows some adsorption peaks that indicate the functional groups on the adsorbent This further suggested that the adsorbent has potential adsorption sites as represented by the functional groups OH, C-H, C-C, and COOH. The results of Physico chemical properties showed that moisture; 8.32±0.07, Ash; 6.31±0.04, lignin; 12.97±0.03, cellulose; 23.53±0.04, Hemicellulose; 16.76±0.02, pectin; 7.74±0.03 and extractives 24.37±0.04. This results showed that this kola nut pod contains considerable amount of lignin, cellulose and hemicelluloses thus, will form a very good adsorbent for removal of dyes and heavy metals in wastewaters. Keyword: modification, characterization, chitosan-oxalic, kola nut pod waste, Physico chemical properties, morphological study.

Effect of H2O/DMF mixed solvents on formation of MIL-100(Fe) and dye adsorption

MIL-100(Fe) with microporous structures is often synthesized under conventional hydrothermal conditions using iron ion and trimesic acid. The effect of H2O/dimethylformamide (DMF) mixtures, with variable H2O volume ratios, on the formation of MIL-100(Fe) was investigated under solvothermal conditions. Pure octahedral MIL-100(Fe) could only be formed in neat H2O or DMF. In most cases, the same reaction in mixed H2O/DMF solvents afforded goethite. When a small volume of H2O was used, morphology resembled coexisting octahedra of MIL-100(Fe) and hexagonal platelets of goethite. A subsequent increase in the H2O content yielded pure hexagonal platelets of goethite and then hexagonal bipyramidal structures of hematite. The surface area and pore volume of MIL-100(Fe) were higher than those of goethite. Dye adsorption tests revealed that 80% of methylene blue (MB) was adsorbed on MIL-100(Fe), synthesized in pure DMF, within 5 ​min, whereas only approximately 26% was adsorbed on MIL-100(Fe) synthesized in pure H2O. This can be attributed to the nanoscale hierarchically porous structures with macroporosity in the DMF-synthesized MIL-100(Fe) and enhanced fast diffusion and mass transfer of dye, which demonstrates its potential as an adsorbent for dye removal. Thus, this study provides a new option of solvent for the formation of nanoscale hierarchically porous MIL-100(Fe) with improved performance in various practical applications.

Coco Peat Organic Manure used as Adsorbents for Dyes Removal

Textile effluents constitute both organic and inorganic constituents and heavy metals which are not economical to treat and hence discharged into water bodies causing water pollution. Methods like ozonation, adsorption, membrane separation, bio sorption, biodegradation, electrochemical degradation, and phytoremediation and H2O2/UV radiation techniques were frequently used for the decolourization of azo dye containing water. Among these aforementioned techniques, the adsorption technique has shown good performance owing to several inherent advantages like high performance, easy handling with no generation of the toxic intermediates. Also dye treatment should be affordable and eco-friendly. Biochar is a sustainable material which can be used for dyes treatment.In this paper, biochar produced using coconut shell was investigated for the removal of methylene blue as the colouring agent. Batch studies were carried out for decolourization of methylene blue based artificial waste water. Different concentrations of methylene blue from 50-300mg/l was used. The validation of the tests was done using data to fit into the Langmuir isotherms and Freundlich isotherm. The adsorption isotherm was well fitted for Langmuir compared to Freundlich. The KL and KF values were also found.

Smart and regeneratable Xanthan gum hydrogel adsorbents for selective removal of cationic dyes

Poly-anionic Xanthan gum-based hydrogels were synthesized and used as potent adsorbents for the removal of dye pollutants from waste water effluents. The adsorbents were synthesized by esterification of Xanthan gum with maleic anhydride, followed by thiol-ene cross-linking chemistry with 2,2′-(ethylenedioxy)diethanethiol. Methylene blue was used as model cationic dye to mimic dye polluted water. The adsorption kinetics of methylene blue by the Xanthan gum-based hydrogels was modeled by pseudo-first-order, pseudo-second-order and intraparticle diffusion models. The experimental adsorption data at 25 °C was modeled by the Langmuir isotherm. The effects of adsorption operation parameters such as the initial dye concentration, pH, ionic strength, and adsorbent dose were also investigated. The pseudo-second-order and Langmuir models were found to be the most appropriate models for the description of the adsorption kinetics and isotherm data, respectively. The Xanthan gum-based hydrogel exhibited a high adsorption capacity of up to qmax=435 mg/g (1.35 mmol/g) towards methylene blue. The incorporation of carboxylic acid groups in the Xanthan gum backbone afforded appreciable charge density at pH > 5, which can effectively facilitate the binding of cationic dye molecules. Consequently, the uptake mechanism of methylene blue by the polyanionic Xanthan hydrogel is attributed mainly to the electrostatic interactions. The Xanthan gum-based hydrogel had a remarkable selectivity for the cationic dye in binary and ternary mixtures of methylene blue with methyl orange or sunset yellow FCF. Finally, the hydrogel showed a potential to be re-used for at least for twenty times after regeneration and maintaining over 95% efficiency dye removal as well as recovery.

Recent Advances in MOF-Based Adsorbents for Dye Removal from the Aquatic Environment

The adsorptive removal of dyes from industrial wastewater using commercially available adsorbents is not significantly efficient. Metal–organic frameworks (MOFs) offer outstanding properties which can boost the separation performance over current commercial adsorbents and hence, these materials represent a milestone in improving treatment methods for dye removal from water. Accordingly, in this paper, the recent studies in the modification of MOF structures in dye removal from the aquatic environment have been discussed. This study aims to elaborate on the synthetic strategies applied to improve the adsorption efficiency and to discuss the major adsorption mechanisms as well as the most influential parameters in the adsorptive removal of dyes using MOFs. More particularly, the advanced separation performance of MOF-based adsorbents will be comprehensively explained. The introduction of various functional groups and nanomaterials, such as amine functional groups, magnetic nanoparticles, and carbon-based materials such as graphene oxide and CNT, onto the MOFs can alter the removal efficiency of MOF-based adsorbents through enhancing the water stability, dispersion in water, interactions between the MOF structure and the contaminant, and the adsorption capacity. Finally, we summarize the challenges experienced by MOF-based materials for dye removal from water and propose future research outlooks to be considered.

Application of amino-functionalized cellulose-poly(glycidyl methacrylate) graft copolymer (AM-Cell-g-PGMA)adsorbent for dyes removal from wastewater

In this work three amino-functionalized cellulose-poly(glycidyl methacrylate) graft copolymers (AM-Cell-g-PGMA) were tested as ion exchange resins for the adsorption of dyes, from aqueous solutions using batch techniques. The three adsorbents were prepared earlier based on the aminization of grafted copolymer with tri-ethylamine hydrochloride (TEAC), di-ethylene tri-amine (DETA) and tri-ethylene tetra-amine (TETA) which represented as R1, R2 and R3 respectively. Adsorption time and solution pH were varied. The maximum adsorption capacities of R1 were 147.5 and 150 (mg/g), while the maximum adsorption capacities of R2 were 117.7 and 133 (mg/g), and finally, the maximum adsorption capacities of R3 were124 and 138 (mg/g) for Acid black 194 and C.I. Reactive black 5 dyestuffs respectively. It was found that the maximum adsorption capacities for the three resins decreased in the order R1> R2> R3 for the sorption of the two dyes. With respect to these results, the R1 resin was then selected for further adsorption investigations regarding isotherm and kinetic studies. The isotherm data were well described by the Langmuir equation over the concentration range studied. Kinetic parameters of sorption were determined enlightening the obeying of the pseudo-second order kinetic model for the investigated system.

Hollow carbon fibers and flakes derived from Calotropis procera as adsorbents for dye removal from aqueous solutions

Plant fibers represent a rich and inexpensive source of easily renewable carbon fibers with various potential applications. In this study, nitrogen-doped carbon flakes (NCFs) and nitrogen-doped hollow carbon fibers (NHCFs) were prepared from Calotropis procera fibers (CPFs) by controlling the conditions of the carbonization process. The pre-oxidation of CPFs plays a vital role in maintaining their morphology after carbonization at high temperature. Scanning electron microscopy (SEM) images confirmed that the carbonized CPFs at 400 οC without pre-oxidation produced NCFs-4, but after carbonization at 500 and 600 οC via the pre-oxidation process, the hollow-fibers retained their morphology and produced NHCFs-5 and NHCFs-6, respectively. Structural characterization of the NCFs and NHCFs was conducted by Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray analysis (EDX), Raman spectroscopy and X-ray diffraction (XRD) and BET analysis. All samples showed a mixture micro/mesoporous structure with a BET surface area of 474.66, 469.29 and 987.80 m2/g for NCFs-4, NHCFs-5 and NHCFs-6, respectively. The prepared NCFs and NHCFs were applied as effective adsorbents for the removal of cationic crystal violet dye (CV) from polluted water. The obtained results showed that the NHCFs-6 sample exhibited a maximum adsorption capacity of 160.18 mg/g. The prepared samples follow the order NHCFs-6 > NCFs-4 > NHCFs-5. The nonlinear Redlich-Peterson model successfully simulated the adsorption isotherm of CV dye removal. The kinetics study demonstrated that the pseudo-first-order (PFO) model is the best model for simulating adsorption kinetics on the NHCFs-6 surface, while the pseudo-second-order model was the best model on the surface of NCFs-4 and NHCFs-5.

Evaluation of using electric arc furnace slag as an adsorbent for dyes removal

ABSTRACT The adsorption of two common textile dyes – orange G and methyl violet – onto an electric arc furnace slag was studied. Batch study shows that adsorption of orange G and methyl violet were dependent highly on pH value. Removal of orange G decreased with the increase of initial pH with optimum pH observed at 3. Moreover, the total removal percentage was low and did not exceed 45% at optimum pH. However, the removal of methyl violet increased with initial pH, and maximum removal (about 94%) was observed at pH 11. Based on the obtained data, methyl violet dye was chosen to study the effect of agitation speed, initial dye concentration, adsorbent dosage and adsorbent particle size on adsorption capacity. For the adsorbent under investigation, equilibrium adsorption capacity qe (mg/g) for orange G and methyl violet dyes were 17.4 mg/g and 3.29 mg/g, respectively. Also, batch studies show that the adsorption rate for methyl violet was rapid at the beginning and slowed down till equilibrium.In contrast, the orange G adsorption rate was slow until it approached equilibrium. The Pseudo-Second order model well represented the kinetics studies data. The value of K2 increased with adsorbent dosage while the K2 value decreased with an increase in initial dye concentration and adsorbent particle size. Equilibrium data were evaluated using Langmuir and Freundlich isotherm models and it was found that the Langmuir isotherm model best fitted to the experiments data.

Biomass-Based Adsorbents for Removal of Dyes From Wastewater: A Review

Dyes, especially azo dyes contained in wastewaters released from textile, pigment, and leather industries, are entering into natural waterbodies. This results in environmental deterioration and serious health damages (for example carcinogenicity and mutagenesis) through food chains. Physiochemical, membrane processes, electrochemical technology, advanced oxidation processes, reverse osmosis, ion exchange, electrodialysis, electrolysis, and adsorption techniques are commonly used conventional treatment technologies. However, the limitations of most of these methods include the generation of toxic sludge, high operational and maintenance costs. Thus, technological advancements are in use to remediate dyes from effluents. Adsorption using the nonconventional biomass-based sorbents is the greatest attractive alternatives because of their low cost, sustainability, availability, and eco-friendly. We present and reviewed up-to-date publications on biomass-based sorbents used for dye removal. Conceptualization and synthesizing their state-of-the-art knowledge on their characteristics, experimental conditions used were also discussed. The merits and limitations of various biosorbents were also reflected. The maximum dye adsorption capacities of various biosorbents were reviewed and synthesized in the order of the biomass type (algae, agricultural, fungal, bacterial, activated carbon, yeast, and others). Surface chemistry, pH, initial dye concentration, temperature, contact time, and adsorbent dose as well as the ways of the preparations of materials affect the biosorption process. Based on the average dye adsorption capacity, those sorbents were arranged and prioritized. The best fit of the adsorption isotherms (for example Freundlich and Langmuir models) and basic operating parameters on the removal dyes were retrieved. Which biomass-based adsorbents have greater potential for dye removal based on their uptake nature, cost-effectiveness, bulk availability, and mono to multilayer adsorption behavior was discussed. The basic limitations including the desorption cycles of biomass-based adsorbent preparation and operation for the implementation of this technology were forwarded.

Facile and scalable preparation of ZIF-67 decorated cotton fibers as recoverable and efficient adsorbents for removal of malachite green

Recently, metal–organic frameworks (MOFs) have received considerable attention as highly efficient adsorbents for dye wastewater remediation. However, the immobilization of MOFs on the substrate surfaces to fabricate easy recyclable adsorbents via a facile route is still a challenge. In this work, ZIF-67/cotton fibers as adsorbents for dye removal were prepared in a large-scale using a simple coordination replication method. The successful fabrication of the ZIF-67/cotton fibers was confirmed by FTIR, XRD, XPS, SEM and BET analysis, respectively. As expected, the as-prepared ZIF-67/cotton fibers exhibited high adsorption capacity of 3787 mg/g towards malachite green (MG). Meanwhile, the adsorption kinetics and isotherm obeyed the pseudo-second-order kinetics and Langmuir model, respectively. Moreover, its removal efficiency towards MG was not significantly influenced by the pH and ionic strength of aqueous solution. Most importantly, the ZIF-67/cotton fibers can remove MG from synthetic effluents, and it can be easily regenerated without filtration or centrifugation processes, with the regeneration efficiency remaining over 90% even after 10 cycles. Additionally, the ZIF-67/cotton fibers presented excellent antimicrobial performance against E. coli and S. aureus. Hence, the distinctive features of the as-prepared ZIF-67/cotton fibers make it promisingly applicable for the colored wastewater treatment.

Removal of hexavalent chromium ions and Acid Red 18 by superparamagnetic CoFe2O4/polyaniline nanocomposites under external ultrasonic fields

In the present research, the adsorptive removal of dye and Cr(VI) ions from the aquatic solutions have been investigated using fabricated magnetic cobalt ferrite (CoFe 2 O 4 ) nanoparticles coated by polyaniline (CoFe 2 O 4 /PANI) via a hydrothermal and in-situ polymerization method. Magnetic composite of CoFe 2 O 4 /PANI was characterized by FE-SEM, EDS, XRD, VSM, FTIR, BET, BJH, and element mapping. The resulting composite was applied for the removal of hexavalent chromium (Cr(VI)) ions and Acid Red 18 (AR18) anionic azo dye individually from an aqueous solution under external ultrasonic fields. The removal efficiency of Cr(VI) ions and AR18 dye were studied as functions of the various parameters like time sonication, amount of adsorbent, initial concentration of Cr(VI) or AR18, and solution pH. The adsorption behavior and the equilibrium data were represented by the Langmuir isotherm model. The maximum monolayer adsorption capacity by as-prepared composite reached 103.11 mg g −1 and 172.41 mg g −1 for Cr(VI) ions and AR18 dye, respectively. The thermodynamic analysis demonstrated that these adsorption processes were spontaneous in nature and endothermic. The magnetically recyclable composite indicated suitable reusability during cyclic adsorption. The increase in ionic strength causes a decrease in the adsorption of Cr(VI) and AR18. This study may provide a promising magnetic composite for the efficient removal of inorganic and organic anions from the water environment. • Application of magnetic CoFe 2 O 4 /PANI for ultrasound assisted adsorption of Cr(VI) ions and AR18 dye. • Desirability function approach combined with CCD method was used to optimize the process variables. • CoFe 2 O 4 /PANI is superior to CoFe 2 O 4 for Cr(VI) ions and AR18 dye adsorption. • The maximum adsorption capacity for Cr(VI) ions and AR18 dye reached 103.11 mg g −1 and 172.41 mg g −1 , respectively. • Reusability tests indicated suitable regenerability of CoFe 2 O 4 /PANI.

Interface Assembly to Magnetic Mesoporous Organosilica Microspheres with Tunable Surface Roughness as Advanced Catalyst Carriers and Adsorbents

Surface roughness endows microspheres with unique and useful features and properties like improved hydrophobicity, enhanced adhesion, improved stability at the oil-water interface, and superior cell uptake properties, thus expanding their applications. Core-shell magnetic mesoporous microspheres combine the advantages of magnetic particles and mesoporous materials and have exhibited wide applications in adsorption, catalysis, separation, and drug delivery. In this study, virus-like rough core-shell-shell-structured magnetic mesoporous organosilica (denoted as RMMOS) microspheres with controllable surface roughness were successfully obtained through electrostatic interaction-directed interface co-assembly. The obtained RMMOS microspheres possess uniform spherical morphology with tunable surface roughness, radially aligned pore channels with a diameter of 3.0 nm in the outer organosilica shell, high specific surface area (396 m2/g), large pore volume (0.66 cm3/g), high magnetization (35.1 emu/g), and superparamagnetic property. The RMMOS microspheres serve as desirable candidates to support Au nanoparticles (2.5 nm) and show superior catalytic activity and excellent stability in hydrogenation of 4-nitrophenol. In addition, the RMMOS microspheres modified with carboxylic groups further displayed promising performance in convenient adsorption removal of dyes in polluted water.