A nature-inspired hydrogen-bonded supramolecular complex for selective copper ion removal from water

Engineering Bis-Pyridine N-Functionalized Cellulose Aerogel for Efficient Extraction of Cu2+ from High-Acidity Wastewaters: Coupling Molecular Scale Interpretation with Experiment

In order to address the issue of protonation of functional groups and structural instability on the surface of aerogel due to strong acidic wastewater, a three-dimensional bis-pyridine N cellulose aerogel [PEIPD/carboxymethyl cellulose (CMC)] with protonation resistance was prepared in this paper by grafting pyridine onto polyethylenimine. The adsorption capacity for Cu2+ of the as-prepared aerogel is as high as 1.64 mmol/g (pH 5) and is maintained well in high-acidity solutions (1.15 mmol/g at pH = 2). It reveals high selectivity, splendid anti-interference ability, and also reliable on the recycle performance. Through the zeta potential tests, this adsorbent reveals a rather low zero charge point (pHpzc = 2.2). The adsorption of Cu2+ on the adsorbent is consistent with the pseudo-second-order kinetic model and the Langmuir model, suggesting that the adsorption process is dominated by chemisorption in a monolayer. The characterizations by Fourier transform infrared spectrometry and X-ray photoelectron spectroscopy proved pyridine N as responsible binding sites, based on which two possible mechanisms are proposed, including chelation and cation-π interaction. Density functional theory calculations are further used to precisely investigate the pathway. By comparing the binding energies, molecular electrostatic potentials, electron densities, and differential charge densities, the bis-pyridine N functional group is finally determined to be of much higher affinity to Cu2+ following chelation reaction as designated. By integrating bis-pyridine N with the CMC and understanding their crucial roles, this will provide significant insights into the rational design of aerogel adsorbents to enhance the recovery of Cu from strongly acidic wastewaters.

Approach of a small protein to the biomimetic bis-(μ-oxo) dicopper active-site installed in MOF-808 pores with restricted access perturbs substrate selectivity of oxidase nanozyme

Advances in nanozymes have taken shape over the past few years in several domains. However, persisting challenging limitations of selectivity, specificity, and efficiency necessitate careful attention to aid in the development of next-generation artificial enzymes. Despite nanozymes having significant therapeutic and biotechnological prospects, the multienzyme mimetic activities can compromise their intended applications. Furthermore, the lack of substrate selectivity can hamper crucial biological pathways. While working on addressing the challenges of nanozymes, in this work, we aim to highlight the interplay between the substrates and bis-(μ-oxo) dicopper active site-installed MOF-808 for selectively mimicking oxidase. This oxidase mimetic with a small pore-aperture (1.4 nm), similar to the opening of enzyme binding pockets, projects a tight control over the dynamics and the reactivity of substrates, making it distinct from the general oxidase nanozymes. Interestingly, the design and the well-regulated activity of this nanozyme effectively thwart DNA from approaching the active site, thereby preventing its oxidative damage. Crucially, we also show that despite these merits, the oxidase selectivity is compromised by small proteins such as cytochrome c (Cyt c), having dimensions larger than the pore aperture of MOF-808. This reaction lucidly produces water molecules as a result of four electron transfer to an oxygen molecule. Such unintended side reactivities warrant special attention as they can perturb redox processes and several cellular energy pathways. Through this study, we provide a close look at designing next-generation artificial enzymes that can address the complex challenges for their utility in advanced applications.

Calcium-Based Metal-Organic Framework: Detection and Idiosyncratic Removal of Copper by Nano-Particle Deposition

A novel calcium-based metal-organic framework (CaMOF@LSB) was designed and synthesized, exhibiting dual functionality for both selective detection and removal of Cu2+ ions from aqueous solutions. The framework's stability, including solvent and pH variations, was established with notable thermal resilience. Colorimetric Cu2+ detection (≥5 ppm) with a high capture capacity of 484.2 mg g-1 by CaMOF@LSB places this material among the few that ensure efficient colorimetric detection and high removal capabilities of Cu2+ ions. Batch adsorption experiments revealed pH-dependent behavior and competitive interactions. Langmuir and pseudo-second-order kinetics models aptly described adsorption isotherms and kinetics, respectively. Thermodynamic assessments confirmed spontaneous and endothermic adsorption. Mechanistically, nanoparticle deposition contributes to the Cu2+ uptake. CaMOF@LSB also exhibited one of the best removal behaviour of Cu2+ by means of oxide formation on the surface. Regeneration of CaMOF@LSB was achieved by simple sonication in 0.1 M aqueous NaOH solution. The recyclability was also tested up to 5 cycles, and it exhibited a small decrease in adsorption capacity observed across the cycles. This research presents a promising avenue for addressing heavy metal pollution using metal-organic frameworks, thereby offering potential applications in water purification and environmental pollution monitoring and remediation.

Copper hexacyanoferrate/carbon sheet combination with high selectivity and capacity for copper removal by pseudocapacitance

The efficient capture of copper ions (Cu2+) in wastewater has dual significance in pollution control and resource recovery. Prussian blue analog (PBA)-based pseudocapacitive materials with open frameworks and abundant metal sites have attracted considerable attention as capacitive deionization (CDI) electrodes for copper removal. In this study, the efficiency of copper hexacyanoferrate (CuHCF) as CDI electrode for Cu2+ treating was evaluated for the first time upon the successful synthesis of copper hexacyanoferrate/carbon sheet combination (CuHCF/C) by introducing carbon sheet as conductive substrate. CuHCF/C exhibited significant pseudocapacitance and high specific capacitance (52.92 F g-1) through the intercalation, deintercalation, and coupling of Cu+/Cu2+ and Fe2+/Fe3+ redox pairs. At 0.8 an applied voltage and CuSO4 feed liquid concentration of 100 mg L-1, the salt adsorption capacity was 134.47 mg g-1 higher than those of most reported electrodes. Moreover, CuHCF/C demonstrated excellent Cu2+ selectivity in multi-ion coexisting solutions and in actual wastewater experiments. Density functional theory (DFT) calculations were employed to elucidate the mechanism. This study not only reveals the essence of Cu2+ deionization by PBAs pseudocapacitance with promising potential applications but also provides a new strategy for selecting efficient CDI electrodes for Cu2+ removal.

MOFs Modulate Copper Trafficking in Tumor Cells for Bioorthogonal Therapy

In situ drug synthesis using the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction has attracted considerable attention in tumor therapy because of its satisfactory effectiveness and reduced side-effects. However, the exogenous addition of copper catalysts can cause cytotoxicity and has hampered biomedical applications in vivo. Here, we design and synthesize a metal-organic framework (MOF) to mimic copper chaperone, which can selectively modulate copper trafficking for bioorthogonal synthesis with no need of exogenous addition of copper catalysts. Like copper chaperones, the prepared ZIF-8 copper chaperone mimics specifically bind copper ions through the formation of coordination bonds. Moreover, the copper is unloaded under the acidic environment due to the dissipation of the coordination interactions between metal ions and ligands. In this way, the cancer cell-targeted copper chaperone mimics can selectively transport copper ions into cells. Regulation of intracellular copper trafficking may inspire constructing bioorthogonal catalysis system with reduced metal cytotoxicity in live cells.

Synthesis of Aminomethylpyridine-Decorated Polyamidoamine Dendrimer/Apple Residue for the Efficient Capture of Cd(II)

Water contamination irritated by Cd(II) brings about severe damage to the ecosystem and to human health. The decontamination of Cd(II) by the adsorption method is a promising technology. Here, we construct aminomethylpyridine-functionalized polyamidoamine (PAMAM) dendrimer/apple residue biosorbents (AP-G1.0-AMP and AP-G2.0-AMP) for adsorbing Cd(II) from aqueous solution. The adsorption behaviors of the biosorbents for Cd(II) were comprehensively evaluated. The maximum adsorption capacities of AP-G1.0-AMP and AP-G2.0-AMP for Cd(II) are 1.40 and 1.44 mmol·g-1 at pH 6. The adsorption process for Cd(II) is swift and can reach equilibrium after 120 min. The film diffusion process dominates the adsorption kinetics, and a pseudo-second-order model is appropriate to depict this process. The uptake of Cd(II) can be promoted by increasing concentration and temperature. The adsorption isotherm follows the Langmuir model with a chemisorption mechanism. The biosorbents also display satisfied adsorption for Cd(II) in real aqueous media. The adsorption mechanism indicates that C-N, N═C, C-O, CONH, N-H, and O-H groups participate in the adsorption for Cd(II). The biosorbents display a good regeneration property and can be reused with practical value. The as-prepared biosorbents show great potential for removing Cd(II) from water solutions with remarkable significance.

Adsorptive removal of heavy metals from wastewater using Cobalt-diphenylamine (Co-DPA) complex

Heavy metals like Cadmium, Lead, and Chromium are the pollutants emitted into the environment through industrial development. In this work, a new diphenylamine coordinated cobalt complex (Co-DPA) has been synthesized and tested for its efficiency in removing heavy metals from wastewater, and its adsorption capacity was investigated. The effectiveness of heavy metals removal by Co-DPA was evaluated by adjusting the adsorption parameters, such as adsorbent dose, pH, initial metals concentration, and adsorption period. Heavy metal concentrations in real sample were 0.267, 0.075, and 0.125 mg/L for Cd2+, Pb2+, and Cr3+ before using as-synthesized Co-DPA to treat wastewater. After being treated with synthesized Co-DPA the concentration of heavy metals was reduced to 0.0129, 0.00028, 0.00054 mg/L for Cd2+, Pb2+, and Cr3+, respectively, in 80 min. The removal efficiency was 95.6%, 99.5%, and 99.5% for the respective metals. The adsorption process fitted satisfactorily with Freundlich isotherm with R2(0.999, 0.997, 0.995) for Cd2+, Pb2+, and Cr3+, respectively. The kinetic data obeyed the pseudo-second order for Cd2+ and Cr2+ and the pseudo-first order for Pb2+. Based on the results obtained within the framework of this study, it is concluded that the as-synthesized Co-DPA is a good adsorbent to eliminate heavy metal ions like Cd2+, Pb2+, and Cr3+from wastewater solution. In general, Co-DPA is a promising new material for the removal of heavy metal ions from water.

Exploring the conformational landscape, hydrogen bonding, and internal dynamics in the diallyl ether and diallyl sulfide monohydrates

The conformational spaces of the diallyl ether (DAE) and diallyl sulfide (DAS) monohydrates were explored using rotational spectroscopy from 6 to 19 GHz. Calculations at the B3LYP-D3(BJ)/aug-cc-pVTZ level suggested significant differences in their conformational behavior, with DAE-w exhibiting 22 unique conformers and DAS-w featuring three stable structures within 6 kJ mol-1. However, only transitions from the lowest energy conformer of each were experimentally observed. Spectral analysis confirmed that binding with water does not alter the conformational preference for the lowest energy structure of the monomers, but it does influence the relative stabilities of all other conformers, particularly in the case of DAE. Non-covalent interaction and quantum theory of atoms in molecules analyses showed that the observed conformer for each complex is stabilized by two intermolecular hydrogen bonds (HBs), where water primarily interacts with the central oxygen or sulfur atom of the diallyl compounds, along with secondary interactions involving the allyl groups. The nature of these interactions was further elucidated using symmetry-adapted perturbation theory, which suggests that the primary HB interaction with S in DAS is weaker and more dispersive in nature compared to the primary HB in DAE. This supports the experimental observation of a tunneling splitting exclusively in the rotational spectrum of DAS-w, as the weaker contact allows water to undergo internal motions within the complex, as shown based on calculated transition state structures for possible tunneling pathways.

Novel α-amino acid-like structure decorated biochar for heavy metal remediation in acid soil

Neither chemical nor physical adsorption play well in heavy metals remediation in acid soil due to the competing behavior of abundant protons, where stable chelators that can be reused are of significant demand. Herein, biochar with abundant nitro and carboxyl groups is prepared, which can be assembled into self-supporting electrode. Under the catalyzation of electricity, the surface decorated -NO2 on the biochar can be in situ transformed into -NH2. Combined with the carboxyl group that attached on the same carbon atom, a special α-amino acid-like structure modified biochar (α-AC@BC) can be successfully constructed. Due to the strong affinity between the α-amino acid-like ligand and heavy metals, this α-AC@BC exhibits high removal efficiencies of 83.41%, 80.94%, 92.54% and 77.05% for available copper, cadmium, lead and zinc respectively, even in a strong acid soil with low pH of 4. After four adsorption-desorption cycles, the α-AC@BC could still eliminate 83.88% of copper. The high adsorption energy among -NH2, -COOH and heavy metals (-2.99 eV for copper, -1.90 eV for lead, -1.30 eV for zinc and -0.91 eV for cadmium) could form steady coordination structure to guarantee a highly practical application potential of α-AC@BC in strong acid soil. This study provides a novel concept for the decontamination of multiple heavy metal polluted acid soil.

Cuproptosis-related LINC02454 as a biomarker for laryngeal squamous cell carcinoma based on a novel risk model and in vitro and in vivo analyses

PURPOSE

Laryngeal squamous cell carcinomas (LSCCs) are aggressive tumors with the second-highest morbidity rate in patients with head and neck squamous cell carcinoma. Cuproptosis is a type of programmed cell death that impacts tumor malignancy and progression. The purpose of this study was to investigate the relationship between cuproptosis-related long non-coding RNAs (crlncRNAs) and the tumor immune microenvironment and chemotherapeutic drug sensitivity in LSCC, and crlncRNA impact on LSCC malignancy.

MATERIALS AND METHODS

Clinical and RNA-sequencing data from patients with LSCC were retrieved from the Cancer Genome Atlas. Differentially expressed prognosis-related crlncRNAs were identified based on univariate Cox regression analysis, a crlncRNA signature for LSCC was developed and validated using LASSO Cox regression. Finally, the effect of LINC02454, the core signature crlncRNA, on LSCC malignancy progression was evaluated in vitro and in vivo.

RESULTS

We identified a four-crlncRNA signature (LINC02454, AC026310.1, AC090517.2, and AC000123.1), according to which we divided the patients into high- and low-risk groups. The crlncRNA signature risk score was an independent prognostic indicator for overall and progression-free survival, and displayed high predictive accuracy. Patients with a higher abundance of infiltrating dendritic cells, M0 macrophages, and neutrophils had worse prognoses and those in the high-risk group were highly sensitive to multiple chemotherapeutic drugs. Knockdown of LINC02454 caused tumor suppression, via cuproptosis induction.

CONCLUSIONS

A novel signature of four crlncRNAs was found to be highly accurate as a risk prediction model for patients with LSCC and to have potential for improving the diagnosis, prognosis, and treatment of LSCC.

Omicron SARS-CoV-2 antiviral on poly(lactic acid) with nanostructured copper coating: Wear effects

Surface modification corresponds to a set of viable technological approaches to introduce antimicrobial properties in materials that do not have such characteristics. Antimicrobial materials are important to prevent the proliferation of microorganisms and minimize the transmission of diseases caused by pathogens. Herein, poly(lactic acid) (PLA) was decorated with nanocones through copper sputtering followed by a plasma etching. Antiviral assays by Quantitative Reverse Transcription-Polymerase Chain Reaction (RT-qPCR) show that nanostructured Cu-coated PLA has high antiviral activity against Omicron SARS-CoV-2, showing a relative reduction in the amplified RNA (78.8 ± 3.9 %). Atomic Force Microscopy (AFM), X-ray Photoelectron Spectroscopy (XPS), and wear-resistance tests show that 20 wear cycles disrupt the surface nanocone patterns and significantly reduce the Cu content at the surface of the nanostructured Cu-coated PLA, leading to total loss of the antiviral properties of nanostructured PLA against Omicron SARS-CoV-2.

Copper removal and recovery from electroplating effluent with wide pH ranges through hybrid capacitive deionization using CuSe electrode

In modern industry, selective extraction and recovery of Cu from strongly acidic electroplating effluent are crucial to reduce carbon emissions, alleviate resource scarcity, and mitigate water pollution, yielding considerable economic and environmental benefits. This study proposed a high-efficiency CuSe electrode to selectively remove Cu from electroplating effluent via hybrid capacitive deionization (HCDI). The potential of this electrode was thoroughly evaluated to assess its effectiveness. The CuSe electrode exhibited superior deionization performance in terms of Cu adsorption capacity, selectivity, and applicability in various water matrices. Specifically, under strong acid conditions (1 M H⁺), the CuSe electrode maintained an optimal adsorption capacity of 357.36 mg g^-1 toward Cu²⁺. In systems containing salt ions, heavy metals, and actual electroplating wastewater, the CuSe electrode achieved a remarkable removal efficiency of up to 90% for Cu²⁺ with a high distribution coefficient K_d. Notably, the capacitive deionization (CDI) system demonstrated the simultaneous removal of Cu-EDTA. The removal mechanism was further revealed using ex-situ X-ray diffraction and X-ray photoelectron spectroscopy analyses. Overall, this study presents a practical approach that extends the capabilities of CDI platforms for effectively removing and recovering Cu from acidic electroplating effluent.

Bioinspired Antimicrobial PLA with Nanocones on the Surface for Rapid Deactivation of Omicron SARS-CoV-2

Bioinspired bactericidal surfaces are artificial surfaces that mimic the nanotopography of insect wings and are capable of inhibiting microbial growth by a physicomechanical mechanism. The scientific community has considered them an alternative method to design polymers with surfaces that inhibit bacterial biofilm formation, suitable for self-disinfectant medical devices. In this contribution, poly(lactic acid) (PLA) with nanocone patterns was successfully produced by a novel two-step procedure involving copper plasma deposition followed by argon plasma etching. According to reverse transcription-quantitative polymerase chain reaction tests, the bioinspired PLA nanostructures display antiviral performance to inactivate infectious Omicron severe acute respiratory syndrome coronavirus 2 particles, reducing the amount of the viral genome to less than 4% in just 15 min due to a possible combined effect of mechanical and oxidative stress. The bioinspired antiviral PLA can be suitable for designing personal protection equipment to prevent the transmission of contagious viral diseases, such as Coronavirus Disease 2019.

Influence of the Crystal Structure of Melamine Trimetaphosphate 2D Supramolecules on the Properties of Polyamide 6

To explore the influence of the crystal structure difference of melamine trimetaphosphate (MAP) on the application performance of its polymer composites, an intumescent flame retardant with the optimal crystal type was designed and synthesized to improve the mechanical properties and flame retardancy of polyamide 6 (PA6). I-MAP and II-MAP were obtained using different concentrations of MA and sodium trimetaphosphate (STMP) in an acidic aqueous solution. The morphology, chemical composition, and thermal stability were comprehensively characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The dispersion, mechanical properties, and flame retardancy of PA6/I-MAP and PA6/II-MAP were evaluated by SEM, stress and strain, limiting oxygen index test (LOI), vertical burning test (UL-94), cone calorimetry (CONE) test, and char residue analysis. The conclusion is as follows: I-MAP and II-MAP have a greater influence on the physical properties of PA6 but less influence on the chemical properties. Compared with PA6/I-MAP, the tensile strength of PA6/II-MAP is 104.7% higher, the flame rating reaches V-0, and PHRR is reduced by 11.2%.

Bacillus coagulans XY2 ameliorates copper-induced toxicity by bioadsorption, gut microbiota and lipid metabolism regulation

Excessive copper pollutes the environment and endangers human health, attracting plenty of global attention. In this study, a novel strain named Bacillus coagulans XY2 was discovered to have a great copper tolerance and adsorption capacity. B. coagulans XY2 might maintain copper homeostasis through multisystem synergies of copper resistance, sulfur metabolism, Fe-S cluster assembly, and siderophore transport. In mice, by promoting the expression of SREBF-1 and SREBF-2 and their downstream genes, B. coagulans XY2 significantly inhibited the copper-induced decrease in weight growth rate, ameliorated dyslipidemia, restored total cholesterol and triglyceride contents both in serum and liver. Furthermore, B. coagulans XY2 recovered the diversity of gut microbiota and suppressed the copper-induced reduction in the ratio of Firmicutes to Bacteroidota. Serum metabolomics analysis showed that the alleviating effect of B. coagulans XY2 on copper toxicity was mainly related to lipid metabolism. For the first time, we demonstrated mechanisms of copper toxicity mitigation by B. coagulans XY2, which was related to self-adsorption, host copper excretion promotion, and lipid metabolism regulation. Moreover, working model of B. coagulans XY2 on copper homeostasis was predicted by whole-genome analysis. Our study provides a new solution for harmfulness caused by copper both in human health and the environment.

Hydrogen bond interactions between thioethers and amides: A joint rotational spectroscopic and theoretical study of the formamide⋯dimethyl sulfide adduct

The rotational spectrum of the binary adduct of formamide (HCONH₂) with dimethyl sulfide (DMS) has been investigated employing cavity-based Fourier transform microwave spectroscopy combined with theoretical computations. Experimentally, only one isomer of the adduct was unambiguously observed and assigned according to the theoretically predicted spectroscopic parameters, and its rotational spectrum displays the hyperfine splittings associated with the ¹⁴N nuclear quadrupole coupling effect. The observed isomer exhibits C_s symmetry, such that the ∠CSC angle of the DMS subunit is bisected by the ab-plane of the HCONH₂ moiety. The two moieties in the detected isomer are connected via one primary NH···S and two secondary CH···O hydrogen bonds. Quantum theory of atoms in molecules (QTAIM), non-covalent interaction (NCI), natural bond orbital (NBO) and symmetry-adapted perturbation theory (SAPT) approaches were utilized for characterizing the intermolecular interactions occurring in the titled adduct. Additionally, the adduct of HCONH₂ with dimethyl ether (DME) was also theoretically investigated to compare the difference in structure and energy characteristics between the NH···S and NH···O hydrogen bonds.

Giant Polyoxoniobate-Based Inorganic Molecular Tweezers: Metal Recognitions, Ion-Exchange Interactions and Mechanism Studies

This work reports the interesting and unique cation-exchange behaviors of the first indium-bridged purely inorganic 3D framework based on high-nuclearity polyoxoniobates as building units. Each nanoscale polyoxoniobate features a fascinating near-icosahedral core-shell structure with six pairs of unique inorganic "molecular tweezers" that have changeable openings for binding different metal cations via ion-exchanges and exhibit unusual selective metal-uptake behaviors. Further, the material has high chemical stability so that can undergo single-crystal-to-single-crystal metal-exchange processes to produce a dozen new crystals with high crystallinity. Based on these crystals and time-dependent metal-exchange experiments, we can visually reveal the detailed metal-exchange interactions and mechanisms of the material at the atomic precision level. This work demonstrates a rare systematic and atomic-level study on the ion-exchange properties of nanoclusters, which is of significance for the exploration of cluster-based ion-exchange materials that are still to be developed.

ROS generation strategy based on biomimetic nanosheets by self-assembly of nanozymes

Reactive oxygen species (ROS) play an important role in physiology and have been applied in tumor therapy. However, insufficient endogenous H₂O₂ and hypoxia in cancer cells can lead to limited ROS production and poor therapeutic efficacy. Herein, we develop a biomimetic nanosheet material based on the self-assembly of nanozymes that could supply H₂O₂ under acidic conditions and catalyze a cascade of intracellular biochemical reactions to produce ROS under both normoxic and hypoxic conditions without any external stimuli. In this system, the copper peroxide nanosheets (CPNS), which are pH-responsive, were prepared through coordination of H₂O₂ to Cu²⁺ and then modified using ultrafine Pt NPs to form CPNS@Pt. The CPNS could decompose under acidic conditions, allowing the simultaneous release of Fenton catalytic Cu²⁺ and H₂O₂ accompanied by a Fenton-type reaction between them. On the other hand, Pt NPs were also released. The released Pt NPs behave as an oxidase mimic and catalase mimic. In this way, the well-defined CPNS@Pt can not only relieve hypoxic conditions but also generate ROS to induce cell apoptosis, thereby paving the way for the development of a nanozyme with multienzyme activity as a therapeutic strategy.

Engineering Polymeric Nanofluidic Membranes for Efficient Ionic Transport: Biomimetic Design, Material Construction, and Advanced Functionalities

Design elements extracted from biological ion channels guide the engineering of artificial nanofluidic membranes for efficient ionic transport and spawn biomimetic devices with great potential in many cutting-edge areas. In this context, polymeric nanofluidic membranes can be especially attractive because of their inherent flexibility and benign processability, which facilitate massive fabrication and facile device integration for large-scale applications. Herein, the state-of-the-art achievements of polymeric nanofluidic membranes are systematically summarized. Theoretical fundamentals underlying both biological and synthetic ion channels are introduced. The advances of engineering polymeric nanofluidic membranes are then detailed from aspects of structural design, material construction, and chemical functionalization, emphasizing their broad chemical and reticular/topological variety as well as considerable property tunability. After that, this Review expands on examples of evolving these polymeric membranes into macroscopic devices and their potentials in addressing compelling issues in energy conversion and storage systems where efficient ion transport is highly desirable. Finally, a brief outlook on possible future developments in this field is provided.

Supramolecular bioamphiphile facilitated bioemulsification and concomitant treatment of recalcitrant hydrocarbons in petroleum refining industry oily waste

Bioremediation of real-time petroleum refining industry oily waste (PRIOW) is a major challenge due to the poor emulsification potential and oil sludge disintegration efficiency of conventional bioamphiphile molecules. The present study was focused on the design of a covalently engineered supramolecular bioamphiphile complex (SUBC) rich in hydrophobic amino acids for proficient emulsification of hydrocarbons followed by the concomitant degradation of total petroleum hydrocarbons (TPH) in PRIOW using the hydrocarbonoclastic microbial bio-formulation system. The synthesis of SUBC was carried out by pH regulated microbial biosynthesis process and the yield was obtained to be 450.8 mg/g of petroleum oil sludge. The FT-IR and XPS analyses of SUBC revealed the anchoring of hydrophilic moieties of monomeric bioamphiphilic molecules, resulting in the formation of SUBC via covalent interaction. The SUBC was found to be lipoprotein in nature. The maximum loading capacity of SUBC onto surface modified rice hull (SMRH) was achieved to be 45.25 mg/g SMRH at the optimized conditions using RSM-CCD design. The SUBC anchored SMRH was confirmed using SEM, FT-IR, XRD and TGA analyses. The adsorption isotherm models of SUBC onto SMRH were performed. The integrated approach of SUBC-SMRH and hydrocarbonoclastic microbial bio-formulation system, emulsified oil from PRIOW by 92.86 ± 2.26% within 24 h and degraded TPH by 89.25 ± 1.75% within 4 days at the optimum dosage ratio of SUBC-SMRH (0.25 g): PRIOW (1 g): mass of microbial-assisted biocarrier material (0.05 g). The TPH degradation was confirmed by SARA fractional analysis, FT-IR, ¹H NMR and GC-MS analyses. The study suggested that the application of covalently engineered SUBC has resulted in the accelerated degradation of real-time PRIOW in a very short duration without any secondary sludge generation. Thus, the SUBC integrated approach can be considered to effectively manage the hydrocarbon contaminants from petroleum refining industries under optimal conditions.

Generation of zinc ion-rich surface via in situ growth of ZIF-8 particle: Microorganism immobilization onto fabric surface for prohibit hospital-acquired infection

Viruses/bacteria outbreaks have motivated us to develop a fabric that will inhibit their transmission with high potency and long-term stability. By creating a metal-ion-rich surface onto polyester (PET) fabric, a method is found to inhibit hospital-acquired infections by immobilizing microorganisms on its surface. ZIF-8 and APTES are utilized to overcome the limitations associated with non-uniform distribution, weak biomolecule interaction, and ion leaching on surfaces. Modified surfaces employing APTES enhance ZIF-8 nucleation by generating a monolayer of self-assembled amine molecules. An in-situ growth approach is then used to produce evenly distributed ZIF-8 throughout it. In comparison with pristine fabric, this large amount of zinc obtained from the modification of the fabric has a higher affinity for interacting with membranes of microorganisms, leading to a 4.55-fold increase in coronavirus spike-glycoprotein immobilization. A series of binding ability stability tests on the surface demonstrate high efficiency of immobilization, >90%, of viruses and model proteins. The immobilization capacity of the modification fabric stayed unchanged after durability testing, demonstrating its durability and stability. It has also been found that this fabric surface modification approach has maintained air/vapor transmittance and air permeability levels comparable to pristine fabrics. These results strongly advocate this developed fabric has the potential for use as an outer layer of face masks or as a medical gown to prevent hospital-acquired infections.

Carbon dioxide-enhanced metal release from kerogen

Heavy metals released from kerogen to produced water during oil/gas extraction have caused major enviromental concerns. To curtail water usage and production in an operation and to use the same process for carbon sequestration, supercritical CO₂ (scCO₂) has been suggested as a fracking fluid or an oil/gas recovery agent. It has been shown previously that injection of scCO₂ into a reservoir may cause several chemical and physical changes to the reservoir properties including pore surface wettability, gas sorption capacity, and transport properties. Using molecular dynamics simulations, we here demonstrate that injection of scCO₂ might lead to desorption of physically adsorbed metals from kerogen structures. This process on one hand may impact the quality of produced water. On the other hand, it may enhance metal recovery if this process is used for in-situ extraction of critical metals from shale or other organic carbon-rich formations such as coal.

Exhausted Cr(VI) Sensing/Removal Aerogels Are Recycled for Water Purification and Solar-Thermal Energy Generation

Heavy metal pollution has resulted in numerous environmental challenges. However, classic approaches, involving the use of solid adsorbents are subject to limitations, including the high energy consumption required for processing before and after use. Accordingly, strategies that facilitate the use of metal capture media that extends beyond waste remediation are attractive. Herein, a porous fluorescent aerogel (CPC aerogel) is constructed by immersing amino-based carbon dots (CDs-NH₂ ) into a polyethyleneimine (PEI)/carboxymethylated cellulose (CMC) aerogel network for the simultaneous detection and adsorption of Cr(VI). Adsorption experiments confirm that the CMC/PEI containing CDs-NH₂ aerogel (CPC aerogel) exhibits good Cr(VI) extraction capacity, and can reach a level that conforms with industrial water safety standards. In addition, the CPC aerogel can continuously detect and remove Cr(VI) at high flux. Following Cr(VI) absorption, the CPC aerogel may be vulcanized (MS_x -CPC gel) and used for solar thermoelectric generation resulting in power generation. Additionally, the MS_x -CPC gel can be used for solar steam generation and exhibits excellent evaporation rates of ≈1.31 kg m^-2 h^-1 under one sun irradiation. The results serve to underscore how materials designed for metal ion recognition and adsorption once exhausted can be exploited to provide materials for solar thermoelectric power generation and seawater desalination.

Copper-Binding Properties of Polyethylenimine-Silica Nanocomposite Particles

Increasing demand for copper resources, accompanied by increasing pollution, has resulted in an urgent need for effective materials for copper binding and extraction. Polyethylenimine (PEI) is one of the strongest copper-chelating agents but is not suitable directly (as is) for most applications due to its high solubility in water. PEI-based composite materials show potential as efficient and practical alternatives. In the present work, the interaction of copper ions with PEI-silica nanocomposite particles and precursor PEI microgels (as a reference) is investigated. It is hypothesized that the main driving force of the reaction is chelation of copper ions by amino groups in the PEI network. The presence of silica in the PEI-silica composites was shown to increase the copper-binding capacity in comparison with the parent microgel. The copper-binding behavior of etched (PEI-free "ghost") composite particles in comparison with the original composites and microgel particles shows that silica nanoparticles in the composite structure increase the number of copper-binding sites in the PEI network rather than adsorbing copper themselves. PEI-silica composites can be easily recycled after copper adsorption by simply washing in 1 M nitric acid, which results in complete copper extraction. Employing this recovery method, PEI-silica composite particles can be used for multiple, efficient cycles of copper removal and extraction.

Nontraditional Redox Active Aliphatic Luminescent Polymer for Ratiometric pH Sensing and Sensing-Removal-Reduction of Cu(II): Strategic Optimization of Composition

Here, redox active aliphatic luminescent polymers (ALPs) are synthesized via polymerization of N,N-dimethyl-2-propenamide (DMPA) and 2-methyl-2-propenoic acid (MPA). The structures and properties of the optimum ALP3, ALP3-aggregate and Cu(I)-ALP3, ratiometric pH sensing, redox activity, aggregation enhanced emission (AEE), Stokes shift, and oxygen-donor selective coordination-reduction of Cu(II) to Cu(I) are explored via spectroscopic, microscopic, density functional theory-reduced density gradient (DFT-RDG), fluorescence quenching, adsorption isotherm-thermodynamics, and electrochemical methods. The intense blue and green fluorescence of ALP3 emerges at pH = 7.0 and 9.0, respectively, due to alteration of fluorophores from -C(═O)N(CH₃ )₂ / -C(═O)OH to -C(O^- )═N⁺ (CH₃ )₂ / -C(═O)O^- , inferred from binding energies at 401.32 eV (-C(O^- )═N⁺ (CH₃ )₂ ) and 533.08 eV (-C(═O)O^- ), significant red shifting in absorption and emission spectra, and peak at 2154 cm^-1 . The n-π* communications in ALP3-aggregate, hydrogen bondings within 2.34-2.93 Å (intramolecular) in ALP3 and within 1.66-2.89 Å (intermolecular) in ALP3-aggregate, respectively, contribute significantly in fluorescence, confirmed from NMR titration, ratiometric pH sensing, AEE, excitation dependent emission, and Stokes shift and DFT-RDG analyses. For ALP3, Stokes shift, excellent limit of detection, adsorption capacity, and redox potentials are 13561 cm^-1 /1.68 eV, 0.137 ppb, 122.93 mg g^-1 , and 0.33/-1.04 V at pH 7.0, respectively.

Design Rules of Hydrogen-Bonded Organic Frameworks with High Chemical and Thermal Stabilities

Hydrogen-bonded organic frameworks (HOFs), self-assembled from strategically pre-designed molecular tectons with complementary hydrogen-bonding patterns, are rapidly evolving into a novel and important class of porous materials. In addition to their common features shared with other functionalized porous materials constructed from modular building blocks, the intrinsically flexible and reversible H-bonding connections endow HOFs with straightforward purification procedures, high crystallinity, solution processability, and recyclability. These unique advantages of HOFs have attracted considerable attention across a broad range of fields, including gas adsorption and separation, catalysis, chemical sensing, and electrical and optical materials. However, the relatively weak H-bonding interactions within HOFs can potentially limit their stability and potential use in further applications. To that end, this Perspective highlights recent advances in the development of chemically and thermally robust HOF materials and systematically discusses relevant design rules and synthesis strategies to access highly stable HOFs.

Highly stable cellulose nanofiber/polyacrylamide aerogel via in-situ physical/chemical double crosslinking for highly efficient Cu(II) ions removal

Water pollution by heavy metal ions is a global concern due to detrimental effects on the ecological environment and human health. To solve the problem of the stability and recyclability of the traditional adsorbents, we proposed three-dimensional lamellar porous cellulose nanofiber/polyacrylamide composite aerogel with outstanding pollutants adsorption, easy regeneration, and multiple recycling. The aerogel adsorbent was prepared by a two-step method via facile in-situ physical/chemical double cross-linking and freeze-drying processes. The resulting aerogels showed good thermal stability, superior water stability and excellent adsorption properties, with a maximum Langmuir adsorption capacity for Cu(II) ions up to 240 mg g^-1 due to the in-situ physical/chemical combination of anionic polyacrylamide and carbonylated cellulose nanofibers. The adsorption mechanism was the electrostatic attraction, chelating effect and complex formation driving forces for the fast and efficient adsorption of Cu(II) ions. The removal efficiency of the aerogels for Cu(II) remained above 80% after 10 adsorption/regeneration cycles, suggesting its outstanding recyclability. The proposed aerogel adsorbent shows noteworthy potential for the practical treatment of heavy metal ion wastewater.

Mixed-Ligand Strategy for the Creation of Hierarchical Porous ZIF-8 for Enhanced Adsorption of Copper Ions

The adsorption of heavy metals using metal-organic framework-based adsorption technology has been pointed out as a promising technique for the removal of these toxic elements from water. However, their adsorption capacity needs to be enhanced. Thus, the current work reports the effect of using a mixed-ligand strategy on the MOF framework and its effect on the removal of copper ions from water by adding terephthalic acid (BDC) linker to the ZIF-8precursors (2-methylimidazole (mI) and Zn²⁺) under solvothermal synthesis, leading to the formation of a hierarchical microporous mesoporous MOF, named Zn-mI-BDC, which was characterized by SEM, EDX, XRD, TGA, BET, and FTIR. As a result, all of these techniques revealed that the addition of a controlled amount of BDC did not alter the crystallinity of ZIF-8, resulting in the creation of a pore size of 4.2 nm. The new hierarchical porous MOF was tested for the adsorption of copper and exhibited an enhanced adsorption capacity compared to pristine ZIF-8 and many other standard adsorbents. The adsorption isotherm matched well with the Langmuir isotherm model, suggesting that the adsorption process chemisorption had a dominant role in the adsorption of Cu²⁺ species. Therefore, the current work is considered as an important step toward the use of a mixed-ligand strategy in enhancing the adsorption capacity of heavy metals using MOF materials.

Versatile metal-organic frameworks as a catalyst and an indicator of nitric oxide

The imaging of nitric oxide (NO) and its donors is crucial to explore NO-related physiological and pathological processes. In this work, we demonstrate the use of Cu-based metal-organic frameworks (Cu-MOFs) as nanoprobes for NO detection and as a catalyst for the generation of NO from the biologically occurring substrate, S-nitrosothiols (RSNOs). The paramagnetic Cu²⁺ in the MOFs could quench the luminescence of triphenylamine; Cu-MOFs only exhibited weak emission at 450 nm. Upon the addition of NO, the paramagnetic Cu²⁺ was reduced to diamagnetic Cu⁺, and thus the luminescence was recovered directly. Cu-MOFs exhibited high selectivity for other species in the reaction system, including NO₂^-, H₂O₂, AA, NO₃^- and ¹O₂. More significantly, the Cu⁺ can react with s-nitrosoglutathione (GSNO), s-nitrosocysteine (CysNO), and s-nitrosocysteamine (CysamNO) to generate NO and then oxidize to Cu²⁺-MOFs with quenched luminescence, respectively, and thus the catalysis is inhibited, noted as a self-controlled process. The Cu-MOFs catalyst was confirmed by powder X-ray diffraction to remain structurally intact in aqueous environments. The Cu-MOFs have been successfully employed in the biological imaging of NO in living cells. The bifunctional MOFs could offer a novel platform for the real-time monitoring of NO species, provide potential for exploiting NO in cancer therapy and improve the methodologies to elucidate the NO-related biological processes.

Sustainable and efficient technologies for removal and recovery of toxic and valuable metals from wastewater: Recent progress, challenges, and future perspectives

Due to their numerous effects on human health and the natural environment, water contamination with heavy metals and metalloids, caused by their extensive use in various technologies and industrial applications, continues to be a huge ecological issue that needs to be urgently tackled. Additionally, within the circular economy management framework, the recovery and recycling of metals-based waste as high value-added products (VAPs) is of great interest, owing to their high cost and the continuous depletion of their reserves and natural sources. This paper reviews the state-of-the-art technologies developed for the removal and recovery of metal pollutants from wastewater by providing an in-depth understanding of their remediation mechanisms, while analyzing and critically discussing the recent key advances regarding these treatment methods, their practical implementation and integration, as well as evaluating their advantages and remaining limitations. Herein, various treatment techniques are covered, including adsorption, reduction/oxidation, ion exchange, membrane separation technologies, solvents extraction, chemical precipitation/co-precipitation, coagulation-flocculation, flotation, and bioremediation. A particular emphasis is placed on full recovery of the captured metal pollutants in various reusable forms as metal-based VAPs, mainly as solid precipitates, which is a powerful tool that offers substantial enhancement of the remediation processes' sustainability and cost-effectiveness. At the end, we have identified some prospective research directions for future work on this topic, while presenting some recommendations that can promote sustainability and economic feasibility of the existing treatment technologies.

Hydrogen-Bonded Framework of a Cobalt(II) Complex Showing Superior Stability and Field-Induced Slow Magnetic Relaxation

A unique hydrogen-bonded organic-inorganic framework (HOIF) constructed from a mononuclear cobalt(II) complex, [Co(MCA)₂·(H₂O)₂] (HMCA = 4-imidazolecarboxylic acid), via multiple hydrogen-bonding interactions was synthesized and structurally characterized. The Co(II) center in the HOIF features a highly distorted octahedral coordination environment. Remarkably, the Co^II HOIF showed permanent porosity with superior stability as established by combined thermogravimetric analysis (TGA), variable-temperature infrared spectra (IR), variable-temperature powder X-ray diffraction data (PXRD), and a CO₂ isotherm. Structural studies reveal that short multiple hydrogen bonds should be responsible for the superior thermal and chemical stability of a HIOF. Magnetic investigations reveal the large easy-plane magnetic anisotropy of the Co²⁺ ions with the fitted D values being 22.1 (magnetic susceptibility and magnetization data) and 29.1 cm^-1 (reduced magnetization data). In addition, the HOIF exhibits field-induced slow magnetic relaxation at low temperature with an effective energy barrier of U_eff = 45.2 cm^-1, indicative of a hydrogen-bonded framework single-ion magnet of the compound. The origin of the significant magnetic anisotropy of the complex was also understood from computational studies. In addition, BS-DFT calculations indicate that the superexchange interactions between the neighboring Co^II ions are non-negligible antiferromagnetism with J_Co-Co = -0.5 cm^-1. The foregoing results provide not only a carboxylate-imidazole ligand approach toward a stable HOIF but also a promising way to build a robust single-ion magnet via hydrogen-bond interactions.

Organogel-assisted porous organic polymer embedding Cu NPs for selectivity control in the semi hydrogenation of alkynes

Heteroatom-rich porous-organic-polymers (POPs) comprising highly cross-linked robust skeletons with high physical and thermal stability, high surface area, and tunable pore size distribution have garnered significant research interest owing to their versatile functionalities in a wide range of applications. Here, we report a newly developed organogel-assisted porous-organic-polymer (POP) supported Cu catalyst (Cu@TpRb-POP). The organogel was synthesized via a temperature induced gelation strategy, employing Schiff-base coupling between 2,4,6-triformylphloroglucinol aldehyde (Tp) and pararosaniline base (Rb). The gel is subsequently transformed to hierarchical porous organic structures without the use of any additive, thereby offering advantageous features including extremely low density, high surface area, a highly cross-linked framework, and a heteroatom-enriched backbone of the polymer. During the semi-hydrogenation of terminal and internal alkynes, the Cu@TpRb-POP-B catalyst with Cu embedded in the TpRb-POP structure consistently demonstrated improved selectivity towards alkenes compared to Cu@TpRb-POP-A, which contains Cu NPs exposed at the exterior surfaces of the POP support. Additionally, Cu@TpRb-POP-B showed higher stability and reusability than Cu@TpRb-POP-A. The superior performance of the Cu@TpRb-POP-B catalyst is attributed to the steric hindrance effect, which controls the product selectivity, as well as the synergistic interaction between the heteroatom-rich POP framework and the embedded Cu NPs. Both the effects are corroborated by experimental characterization of the catalysts and density functional theory (DFT) calculations.

Macroporous chitin microspheres prepared by surfactant micelle swelling strategy for rapid capture of lead (II) from wastewater

Heavy metal pollution of water source continues to be one of the most serious environmental problems which have attracted major global concern. Here, a macroporous chitin microsphere is prepared by surfactant micelle swelling strategy followed by modification with tetraethylenepentamine for Pb²⁺ removal from wastewater. The resultant adsorbent not only exhibits fast adsorption kinetic (>80% of its equilibrium uptake within 20 min) but also has high adsorption capacity of 218.4 ± 6.59 mg/g and excellent reusability (>75% of its initial adsorption capacity after five adsorption/desorption cycles). More importantly, under the continuous operating mode, the adsorbent can treat about 39,000 kg water/kg adsorbent, and the Pb²⁺ concentration decreases from 2000 μg/L to smaller than 10 μg/L, meeting the drinking water standard recommended by the World Health Organization (10 μg/L). All results indicate that the tetraethylenepentamine-modified macroporous chitin microspheres have great potential in the treatment of heavy metal contamination.

Synthesis and Characterization of Polyethylenimine-Silica Nanocomposite Microparticles

A novel procedure for the synthesis of polyethylenimine (PEI)-silica nanocomposite particles with high adsorption capacities has been developed based on an emulsion templating concept. The exceptional chelating properties of PEI as the parent polymer for the particle core promote the binding abilities of the resulting composite for charged species. Further, the subsequent introduction of silica via the self-catalyzed hydrolysis of tetraethoxysilane facilitates production of robust composite particles with smooth surfaces, enabling potential use in multiphase environments. To enable tailored application in solid/liquid porous environments, the production of particles with reduced sizes was attempted by modulating the shear rates and surfactant concentrations during emulsification. The use of high-speed homogenization resulted in a substantial decrease in average particle size, while increasing surfactant loading only had a limited effect. All types of nanocomposites produced demonstrated excellent binding capacities for copper ions as a test solute. The maximum binding capacities of the PEI-silica nanocomposites of 210-250 mg/g are comparable to or exceed those of other copper binding materials, opening up great application potential in resources, chemical processing, and remediation industries.

Hydrogen Bonding with Polonium

Hydrogen bonding (H-bonding) with heavier chalcogens such as polonium and tellurium is almost unexplored owing to their lower electronegativities, providing us an opportunity to delve into the uncharted territory of...

Coordination-bond-directed synthesis of hydrogen-bonded organic frameworks from metal-organic frameworks as templates

Controlled synthesis of hydrogen-bonded organic frameworks (HOFs) remains challenging, because the self-assembly of ligands is not only directed by weak hydrogen bonds, but also affected by other competing van der Waals forces. Herein, we demonstrate the coordination-bond-directed synthesis of HOFs using a preformed metal-organic framework (MOF) as the template. A MOF (CuI-TTFTB) based on two-coordinated CuI centers and tetrathiafulvalene-tetrabenzoate (TTFTB) ligands was initially synthesized. CuI-TTFTB was subsequently oxidized to the intermediate (CuII-TTFTB) and hydrated to the HOF product (TTFTB-HOF). Single-crystal-to-single-crystal (SC-SC) transformation was realized throughout the MOF-to-HOF transformation so that the evolution of structures was directly observed by single-crystal X-ray diffraction. The oxidation and hydration of the CuI center are critical to breaking the Cu-carboxylate bonds, while the synergic corbelled S⋯S and π⋯π interactions in the framework ensured stability of materials during post-synthetic modification. This work not only provided a strategy to guide the design and discovery of new HOFs, but also linked the research of MOFs and HOFs.

Husbandry waste derived coralline-like composite biomass material for efficient heavy metal ions removal

The resource utilization of biological solid waste is crucial for practical environmental remediation. By comprehensively utilizing LiBr treatment and dopamine chemistry, herein the cow dung waste was successfully converted into the composite biomass material for efficient heavy metal ions removal. A selective etching mechanism of cellulose was discovered in the LiBr treatment process, achieving the large-scale preparation of coralline-like porous biomass material with hundred times increased specific surface. Benefiting from the co-deposition of polyethyleneimine and Fe₃O₄, the fabricated material showed significantly higher adsorption capacity (183.82 and 231.48 mg·g^-1 for Cu²⁺ and Cd²⁺) than that of raw cow dung (0.95 and 1.25 mg·g^-1 for Cu²⁺ and Cd²⁺). Furthermore, this composite biomass adsorbent also exhibited rapid adsorption equilibrium, magnetic separation capability, monolayer chemisorption feature and feasible recycling use. Collectively, this work contributes to both the resource utilization of husbandry solid waste and the development of advanced biomass adsorbent.

Self-Assembly of Nitrogen-Rich Heterocyclic Compounds with Oxidants for the Development of High-Energy Materials

The development of energetic materials with high energy and low sensitivity has attracted immense interests due to their widespread applications in aerospace technology and national defense. In this work, a promising self-assembly strategy was developed to prepare three high-energy materials (1-3) through the introduction of oxidant molecules into the crystal voids of the parent materials. The structures of these new materials were comprehensively examined by infrared spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and single-crystal X-ray diffraction. In these materials, three unique layer structures with hcb, sql, and interrupted sql topologies were observed, which were formed by the fused-ring-based energetic components. Windows with hexagonal, square, and rectangular structures were observed within these layer structures, which were occupied by H₂O₂, NO₃^-, and ClO₄^-, respectively. Oxidant molecules interacted with parent molecules via hydrogen bonds to form crystal structures of these materials. Moreover, the energetic property of these materials was estimated by computing methods. The calculation results revealed that these self-assembly materials exhibit excellent energetic properties. The highest energetic performance was observed for compound 3. The detonation velocity, detonation pressure, and specific impulse values were up to 9339 m·s^-1, 42.5 GPa, and 308 s, respectively, which were greater than those of HMX. Furthermore, these materials exhibited good sensitivity, which was closely related to their unique crystal structures. The high performance of these materials indicated that the self-assembly strategy should be a promising method for the development of novel energetic materials.

Equilibrium and thermodynamic investigation of biosorption of nickel from water by activated carbon made from palm kernel chaff

Novel biosorbents were derived from a waste product of palm kernel oil extraction known as palm kernel chaff (PKC). One portion of the PKC was carbonized in a furnace and then activated chemically, while the other half was activated without carbonization. Both were designated as CPKC and UPKC, respectively. The two biosorbents so produced were then used to conduct batch equilibrium and kinetic sorption studies at 30 °C, 35 °C and 40 °C and pH 3.0 and 9.0 for an agitation period of 5, 10, 20, 40, 60, 90, and 120 min. The Koble-Corrigan, Dubinin-Radushkevich, and the Freundlich isotherms fitted the experimental data very well with R² values of 0.97 to 1.0, 0.95 to 1.0, and 0.96 to 1.0, respectively. The linear type II Langmuir isotherm performed much better (0.96 ≤ R² ≤ 1.0) than the nonlinear isotherm. The maximum sorption capacity was obtained as 120.6 mg/g using CPKC at pH 9.0 and 35 °C. The Langmuir separation coefficient values (0.022 ≤ R_L ≤ 0.926) show that the sorption of nickel to PKC is favorable. The most favorable sorption condition was found for CPKC at pH 9 and temperature of 40 °C. The values of sorption energy (8.21 ≤ E ≤ 14.27) and the isosteric heat of sorption (-133.09 ≤ ∆H_x ≤ -17.92) indicate that the mode of sorption is mostly ion exchange. Thermodynamic parameters also show that the process is exothermic and entropy-driven. The pseudo-second-order kinetic model shows the best correlation compared to the other kinetic models. The coefficient of correlation for the pseudo-second-order model was mostly within the range of 0.999-1.000 for 90% of all kinetic studies carried out.