Adsorption Rate Research Articles

Adsorption and evolution of N2 molecules over ZnO monolayer: a combined DFT and kinetic Monte-Carlo insight

A large surface area, wide band gap, and unique bonding property between Zn and O atoms make the hexagonal ZnO monolayer attractive as a gas sensor. In the present work, the adsorption and evolution of nitrogen (N2) molecules over a ZnO monolayer have been studied using two different theoretical methods: van der Waals density functional theory (vdW-DFT) and kinetic Monte-Carlo (kMC) simulation. The adsorption and diffusion (hopping over the surface) energy of a N2 gas molecule has been calculated considering the different sites over the ZnO substrate using the revPBE-vdW functional. Bader charge, electron localization function analysis, density of states and band structure plotting have been used to understand the adsorption mechanism. Lateral repulsive interaction between two N2 molecules limits the maximum packing number of gas molecules within one hexagonal ring. The output of the vdW-DFT calculation has been fed to the kMC code to predict the rate of adsorption, desorption, and diffusion, along with the overall surface coverage at different temperatures and pressures. Finally, the change in the N2 adsorption energy has been predicted with the increase of the ZnO layer number.

Investigation of the biological removal of nickel and copper ions from aqueous solutions using mixed microalgae

AbstractThe use of mixed microalgae offers an effective solution for the management of contamination risks in cultivation while enhancing economic viability. In this study, mixed microalgae were used for the first time for the removal of copper (Cu) and nickel (Ni) from aqueous solutions. The characteristics of the adsorbents were examined thoroughly, and the adsorption process was assessed using isotherms, kinetics, and thermodynamics. Particle size, concentration, contact time, temperature, and pH were among the variables assessed. The findings demonstrated that, at an initial concentration of 100 mg L–1 and a pH of 6, the maximum adsorption of Cu with a particle size of 1 mm (90.20%) took place in 60 min. The highest adsorption rate (78.25%) was found for Ni. Microalgae performed best over 180 min at room temperature and at pH values that promoted metal dissolution. The removal percentages of wet and dried microalgae were comparable, and the wet adsorbent was more economical. It was feasible to remove both metals at the same time. Up to three cycles of adsorbent reuse were possible, with sodium hydroxide treatment offering superior removal to hydrochloric acid. Thermodynamic analysis demonstrated that this process, which results in a disordered state, is exothermic and spontaneous.

Graphene aerogel with double pore structure for marine oil spill emergency response

Due to its high porosity, large specific surface area, and strong photothermal conversion performance, graphene aerogel has unique advantages in the field of pollution treatment, especially in the field of recovering highly viscous oils. However, for the treatment of highly viscous oils, the high adsorption capacity and high adsorption rate of graphene aerogel often cannot be combined, which is one of the important reasons limiting its development in this field. A double-step templating strategy for graphene aerogels preparation was used in this work, i.e., Pickering emulsion soft templating and unidirectional freeze casting. Specifically, the dense Pickering emulsion droplets can be stabilized in a short period of time, so that they can be cured quickly. After that, graphene aerogels (DGA-0.8-25) with dual pore structure were prepared by unidirectional freeze casting technology to further form aligned pores based on the pores formed by the Pickering emulsion droplet soft template. The dense presence of Pickering emulsion droplets gives DGA-0.8-25 an ultra-high porosity (96.8 %), which can adsorb 184.53 times its own mass of crude oil. Due to the unidirectional pore structure, the adsorption rate of DGA-0.8-25 on crude oil is as high as 8.39 g·g−1·min−1, which realizes dual improvement of the adsorption capacity and rate of graphene aerogel on crude oil and shows a good application prospect in the treatment of high viscosity crude oil. In addition, DGA-0.8-25 has unique advantages in the field of oil–water separation, with a separation efficiency of 99.04 % for water-in-oil emulsions and 97.63 % for oil-in-water emulsions. When repeated used in photothermal adsorption of highly viscous oil, DGA-0.8-25 can still maintain more than 90.61 % of its initial adsorption capacity after ten cycles of use-regeneration. Because of its unique advantages such as high efficiency and low cost, DGA shows promising in its future large-scale use.

Effect of Water Content on Light Nonaqueous Phase Fluid Migration in Sandy Soil

Contamination from light nonaqueous phase fluids (LNAPLs) and their derivatives during mining, production, and transportation has become a concern. Scholars have extensively studied LNAPL contamination, but the role of water content variation on its migration process in the unsaturated zone has not been sufficiently researched. The specific issue addressed in this study is the impact of water content on the migration of light nonaqueous phase liquids (LNAPLs) in sandy soils, a critical yet under-researched aspect of subsurface contamination. To tackle this, we employed indoor simulated vertical, one-dimensional, multiphase flow soil column experiments, utilizing the orthogonal experimental method to systematically evaluate the effects of varying water contents on the occurrence state and migration rate of LNAPLs. The experimental results indicate the following: (1) The migration rate of LNAPL exhibits an L-shaped trend during subsurface imbibition and a nonlinear relationship with migration time. The migration rate and migration time of surface infiltration have a linear growth relationship. (2) The residual rate of LNAPL is negatively correlated with water content and positively correlated with oil content in the homogeneous non-saturated state. With the increase in the amount of leaked oil, 40% of the leaked LNAPL is sorbed within the soil. (3) When the water content of the test medium is below 14%, and the oil content is below 11%, LNAPL appears in the unsaturated zone in a solid phase. As the water content increases, the adsorption rate of the oil phase gradually decreases and eventually reaches the oil saturation point. (4) When the water content of the medium exceeds 8%, over time, LNAPL will be subject to oil–water interfacial tension, and the rate of LNAPL movement first decreases and then increases, displaying nonlinear growth. The innovation of this work lies in the comprehensive analysis of LNAPL migration under controlled laboratory conditions, providing results that enhance the understanding of LNAPL behavior in sandy soils. These quantitative insights are crucial for developing targeted remediation strategies for LNAPL-induced pollution in the unsaturated zone.

The fate of Cd in Soils with Various Particle Sizes: Characteristics, Speciation Distribution and Influencing Factors.

This study investigated the distribution of Cd in soil water-stable aggregate particles of varying sizes, revealing that smaller particles have higher total Cd content as well as different forms of Cd content, with the clay particle showing a greater tendency to accumulate Cd. However, the proportion of high activity Cd is lower in clay particles, posing a lower environmental risk of Cd transformation compared to silt particles. Adsorption experiments indicated that the clay particle exhibits the strongest adsorption capacity and highest adsorption rate. Additionally, correlation and principal component analyses identified Fe-Mn oxides and organic matter as the primary influencing factors on Cd distribution characteristics, with pH playing a secondary role. These findings provide valuable insights for the remediation of heavy metal-contaminated soil.

Study on the Gas Desorption Regularity of Coal Lumps of Different Sizes under Different Water Inundation Conditions

Coal mining can create a large number of abandoned areas, which contain rich coalbed methane resources. The adsorption principle of the residual gas left in the abandoned coal seam is an important part of the coalbed methane resources. The adsorption principle is of great significance for the evaluation of coalbed methane resources in abandoned coal seams. However, due to the complex environment in abandoned coal seams, the factors affecting the adsorption of residual gas in abandoned coal seams are also complex. Among them, water is an important factor that affects the adsorption of residual gas in abandoned coal seams. The study on the adsorption of residual gas in abandoned coal seams with different water infiltration conditions is less. Therefore, a block coal water-flooding gas adsorption device was developed for the study of block coal gas adsorption, and the adsorption rate of block coal gas under different water infiltration conditions was determined experimentally.

Metal-organic-framework and walnut shell biochar composites for lead and hexavalent chromium removal from aqueous environments.

Extensive research in recent years has explored the realm of porous carbon composites for various applications, including electrochemistry, structural materials, environmental remediation, and more. In particular, the fabrication of porous carbon composites using a metal-organic framework (MOF) and biochar (BC) for aqueous remediation is a fairly new avenue of research. In this study, a MOF-BC composite was synthesized with unmodified and chemically modified BCs using solvothermal synthesis. The composites were used as adsorbents to remediate heavy metals, such as lead (II) and chromium (VI), from aqueous environments. It was verified that the MOF was homogeneously deposited onto the BC's surface using various material characterization techniques. Lead and chromium adsorption studies revealed a high adsorption capacity with greater than 99% removal for lead and ∼65% for chromium, respectively. Impressively, for lead, the highest observed experimental adsorption capacity of the MOF-chemically modified BC composite was 535 mg/g, compared to 240 mg/g for pristine BC. Meanwhile, the adsorption capacity of the same MOF-BC composite for chromium ions was low at 18 mg/g, compared to 80 mg/g for the chemically modified BC. The MOF-BC had a rapid adsorption rate, achieving equilibrium at only 150 min of reaction time for lead ions. MOF-BCs have higher adsorption for cationic lead through physisorption and ion-exchange mechanisms, whereas, for anionic chromium, removal is dominated only by physisorption mechanisms. The outcomes and methodological developments attained in this study offer a novel and compelling approach for synthesizing MOF-BC composites for aqueous remediation applications.

Growth stage-related capsular polysaccharide translocon Wza in Vibrio splendidus modifies phage vB_VspM_VS2 susceptibility

Bacteria at different growth stages usually coordinate capsular polysaccharide (CPS) formation and may affect their susceptibility to phage. In this study, we evaluated the infection efficacy of phage vB_VspM_VS2 in V. splendidus AJ01 at different growth stages and explored the role of growth stage-related CPS translocon Wza in the susceptibility of V. splendidus to phage vB_VspM_VS2. The results showed that V. splendidus locked in the stationary growth stage (SGS) or early exponential stage (EES) infected with phage (EES-P) has a low susceptibility to phage vB_VspM_VS and exhibit a pronounced reduction in phage adsorption rate as compared to the EES bacteria. The expression of wza of CPS transport gene was significantly increased in EES bacteria compared to that bacteria locked in the SGS or EES-P. Bacteria with deleted wza (Δwza mutant) escaped phage adsorption due to absence of Wza mediated down-regulation of CPS expression, otherwise. Our results reveal that the Wza of V. splendidus can promotes phage to infect these bacteria via increasing the phage absorption, which provides important implications for using phages therapeutically target pathogenic bacteria in dynamics communities.

In-Situ construction of Bulge-like microstructures in sugarcane-based superhydrophobic membranes for efficient separation of water-in-oil emulsions

The separation of oil/water pollution is of great importance to environmental protection. However, the development of superwetting materials for efficient separation of surfactant-stabilized oil/water emulsions still faces challenges. As agricultural waste, sugarcane straw contains many hydrophilic groups and multilayered pore structures, making it suitable for purifying oil/water emulsions by simple chemical modification treatments. Herein, sugarcane-based superhydrophobic membranes (SSMs) were prepared by a facile vacuum impregnation method in hexadecyltrimethoxysilane (HDTMS) solution. The unique bulge-like microstructures were constructed in the intrinsic pores of sugarcane, which significantly increased the roughness and resulted in superhydrophobicity with the water contact angle of 153.5°. More importantly, the bulge-like structure is easy to break the emulsion and thus SSMs offer excellent separation efficiency (> 99 %), suitable fluxes (368 L•m−2•h−1) and strong cycling stability for surfactant-stabilized water-in-oil emulsions. In addition, SSMs can separate oil/water mixtures and directly adsorb oil from water with adsorption rates exceeding 99 %. SSMs have good durability and anti-mold adherence properties, and they do not lose their unique wetting properties even in harsh environments. More importantly, SSMs can be degraded in soil at the end of their life cycle, avoiding secondary pollution for the environment. This simple, in-situ impregnation technique offers a novel way to create green, inexpensive and stable biomass membranes for effective water-in-oil emulsion separation, showing great promise for use in oily wastewater treatment.

Exploiting RSM and ANN modeling methods to optimize phosphate ions removal using LDH/alginate composite beads

In the present work, layered double hydroxide (MgAl) and alginate composite beads (LDH/alginate) were developed and used as low-cost and environmentally friendly adsorbent for phosphate ions removal. The successful incorporation of sodium alginate into the LDH structure was confirmed through SEM analysis. The dried beads exhibited a notably rough surface, which promotes molecular movement and potentially enhances pollutant adsorption. The pH of zero charge point (pHPZC) of the composite was found to be 7.41. This result implies that negative ions have a tendency to draw positive charges on the adsorbent surface via electrostatic interaction forces when the pH is lower than the pHPZC. On the other hand, a surface that has a pH higher than pHPZC mostly has a negative charge. The percentage removal and adsorption capacity were investigated as a function of contact time.Experiments were carried out by simultaneously varying three factors, in order to evaluate and compare the predictive capabilities of the response surface methodology (RSM) and the artificial neural network approach (ANN) for the adsorption process. Both methods demonstrated a strong ability to accurately predict the adsorption process. However, the response surface methodology exhibited a lower prediction error compared to the artificial neural network approach.The central composite design within response surface methodology (CCD-RSM) was employed to optimize the experimental conditions for the adsorption process. The model, which considers three factors: adsorbent dose (A), initial concentration (B), and contact time (C), proved to be significant. Among these, the quadratic term (B2) had the most substantial impact on the phosphate ion adsorption rate. The analysis yielded an R2 value of 0.94, indicating an excellent fit to the data. The findings suggest that increasing contact time and reducing the initial concentration improve phosphate ion removal efficiency, while the adsorbent dose has little to no effect. The Artificial Neural Network (ANN) model effectively predicted the adsorptive remediation of phosphate ions onto LDH/alginate composite beads, achieving a high coefficient of determination (R2 = 0.984) between the model outputs and the experimental data. The study highlights the significant potential of LDH/alginate composite beads as a natural adsorbent for the removal of phosphate ions from aqueous solutions. These results underscore the environmental friendliness and efficiency of the adsorbent used for phosphate adsorption.

Preparation and adsorption application of PLA/GO/PDA nanofiber membrane

Abstract In this study, PLA(polylactic acid)/GO(graphene oxide)/DA(Dopamine) porous nanofiber membrane was prepared by electrospinning. L16(43) orthogonal experiment was designed to investigate the effects of reaction temperature, reaction time, and DA concentration on the adsorption performance of DA oxidized and self-polymerized on the fiber. Based on the characterization of scanning electron microscopy and the determination of the adsorption performance of the fiber membrane to MB(methylene blue dye), data visualization analysis, variance analysis, and F-test were conducted to determine the optimal process parameters: reaction temperature of 45 ℃, reaction time of 30 h, and DA concentration of 2 mg/ml. PLA/GO/PDA(Polydopamine) nanofiber was prepared and characterized under the optimal process parameters. The results showed that the average diameter of the PDA-loaded nanofiber increased from 737 nm to 996 nm, and a layer of PDA with a thickness of about 129 nm was loaded on the outer surface of the fiber, making the contact angle of the fiber membrane with 0° and becoming a hydrophilic material. In adsorption performance testing of MB, the PLA/GO/PDA nanofiber membrane prepared based on the PLA/GO/DA fiber membrane with an adsorption rate of 98.81 % in 24 h was superior to the PLA/GO/PDA nanofiber membrane prepared based on the PLA/GO fiber membrane.

Removal of cefuroxime from aqueous solution by biochars derived from antibiotic mycelial residue.

In China, antibiotic mycelial residue is categorized as hazardous waste. To achieve the harmless and resourceful disposal of cephalosporin, three types of biochars from cephalosporin mycelia residues, namely non-activated carbon (BC1), ZnCl2-activated carbon (BC2), and KOH-activated carbon (BC3), were respectively fabricated by high-temperature pyrolysis carbonization technology. These three kinds of biochars were characterized via iodine value, FTIR, and SEM, and the adsorption performance of the prepared biochars was investigated using cefuroxime (CXM) as the adsorption target. The results indicated that BC3 biochar possesses the most well-developed pores and the highest iodine value of 1367.41 mg/g; The most suitable dosage is 1.6 g/L, and the lower the pH, the more favorable the adsorption effect. The investigation of adsorption kinetics revealed that it conformed to the kinetic model of pseudo-second order, as well as the process of adsorption was governed by the chemical adsorption mechanism, the rate of adsorption was affected by the collective impact of the quantity of active sites present and the interaction strength between the CXM molecules and the biochar. The exploration of adsorption thermodynamics revealed that it aligned with the Langmuir model, the surface of biochar was relatively uniform, and the adsorption was mainly of low coverage; The calculation of thermodynamic parameters demonstrated that the adsorption was exothermic and spontaneous.

A multifunctional superhydrophobic phase‐change photothermal coating for concrete anti‐icing

AbstractSuperhydrophobic coatings meet the urgent need for anti‐icing infrastructure in low‐temperature environments but suffer limited functionality and easy failure. Carbon nanotubes (CNTs) with highly efficient photothermal conversion properties can address these issues when endowed with superhydrophobicity. However, CNTs face challenges in modification and functional failure without light. This study proposes a simple strategy to endow CNTs with superhydrophobic and phase‐change properties, affording CNTs with superhydrophobic photothermal phase‐change functions. The phase‐change superhydrophobic photothermal CNT (PSC) particle size distribution was optimized to 4–6 μm, effectively reducing CNT agglomeration tendency. The PSC exhibited good phase‐change enthalpy, with a 53% phase‐change material adsorption rate. Superhydrophobic coatings based on PSC were prepared via a two‐step method. The primer performed best with a 10% silicon carbide to epoxy resin mass ratio. Considering performance and economy, optimal coating performance occurred with 100 mg of PSC in the topcoat. The PSC coating achieved a 156.7° contact angle and a rolling angle of only 3.4°. It can rapidly warm from −10 to 50 °C under one solar intensity. The coating exhibits excellent robustness across extreme environments, extending droplet freezing time by 10‐fold at −10 °C and quickly melting under one sun intensity. This research will further advance the development of CNT‐based superhydrophobic photothermal coatings and promote their application in infrastructure sectors, particularly for cement concrete. © 2024 Society of Chemical Industry.

Kinetic study of paraquat adsorption on alginate beads loaded with montmorillonite using shrinking core model

Water contamination by pesticides threatens clean water availability, highlighting the need for advanced sustainable sanitation systems. Adsorption using biopolymers and minerals is prominent. Understanding process kinetics and influencing parameters is crucial for optimizing contaminant-adsorbent contact time for safe water disposal. The adsorption kinetics of Paraquat (PQ) at three initial concentrations (C0 = 19, 38, and 50 ppm) were studied using alginate-montmorillonite (Alg-Mt) beads with varying clay contents and a 30-min gelation time. The beads were characterized by elemental analysis, TG/DTG, FTIR, XRD, SEM, and EDX. The Shrinking Core Model (SCM) was applied to the experimental data to determine if the diffusion of PQ within the beads depended on clay content. The effective diffusion coefficient (Dp) in the adsorbent increased from 7 × 10−12 to 1 × 10−10 m2 s−1 with increasing clay content, suggesting that diffusion into the interior depended on interaction with the mineral.This investigation also demonstrated that the synthesis of beads at different gelation times does not impact either the adsorption capacity or the adsorption rate of the herbicide on the materials. These results indicate that diffusion depends solely on the interaction of the cationic herbicide with the clay encapsulated within the bead hydrogel.

A Sustainable Solution for the Adsorption of C.I. Direct Black 80, an Azoic Textile Dye with Plant Stems: Zygophyllum gaetulum in an Aqueous Solution.

The presence of pollutants in water sources, particularly dyes coming by way of the textile industry, represents a major challenge with far-reaching environmental consequences, including increased scarcity. This phenomenon endangers the health of living organisms and the natural system. Numerous biosorbents have been utilized for the removal of dyes from the textile industry. The aim of this study was to optimize discarded Zygophyllum gaetulum stems as constituting an untreated natural biosorbent for the efficient removal of C.I. Direct Black 80, an azo textile dye, from an aqueous solution, thus offering an ecological and low-cost alternative while recovering the waste for reuse. The biosorbent was subjected to a series of characterization analyses: scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET) method, X-ray diffraction (XRD), and infrared spectroscopy (IR) were employed to characterize the biosorbent. Additionally, the moisture and ash content of the plant stem were also examined. The absorption phenomenon was studied for several different parameters including the effect of the absorption time (0 to 360 min), the sorbent mass (3 to 40 g/L), the pH of the solution (3 to 11), the dye concentration (5 to 300 mg/L), and the pH of the zero-charge point (2-12). Thermodynamic studies and desorption studies were also carried out. The results showed that an increase in plant mass from 3 to 40 g/L resulted in a notable enhancement in dye adsorption rates, with an observed rise from 63.96% to 97.08%. The pH at the zero-charge point (pHpzc) was determined to be 7.12. The percentage of dye removal was found to be highest for pH values ≤ 7, with a subsequent decline in removal efficiency as the pH increased. Following an initial increase in the amount of adsorbed dye, equilibrium was reached within 2 h of contact. The kinetic parameters of adsorption were investigated using the pseudo-first-order, pseudo-second-order and Elovich models. The results indicated that the pseudo-first-order kinetic model was the most appropriate for the plant adsorbent. The isotherm parameters were determined using the Langmuir, Frendlich, Temkin, and Dubinin-Radushkevich models. The experimental data were more satisfactory and better fitted using the Langmuir model for the adsorption of dye on the plant. This study demonstrated that Zygophyllum gaetulum stems could be employed as an effective adsorbent for the removal of our organic dye from an aqueous solution.

Application of a Discrete AlGaN/GaN HEMT Sensor for in‐situ Regenerative Soot Particulate Detection

AbstractAn in‐situ regenerative soot particulate matter sensor for automotive exhaust systems based on a discrete AlGaN/GaN high electron mobility transistor (HEMT) was developed and tested, where charge‐sensitive AlGaN/GaN HEMT was utilized to detect the signal variations caused by the presence of soot particulate matters, and the micro‐hotplate serves as soot deposition, while the self‐heating unit was used for sensing and in‐situ regeneration. The two parts were connected for electrical signal transmission. Soot particulate were generated by a laminar diesel flame with an adsorption rate of 23.29 μg cm−2 min−1 on the sensor surface, resulting in 1.32% sensing response after 20 s deposition and reached saturation after a 12 minute deposition of soot. After soot deposition, the sensor was successfully regenerated when a voltage of 2 V was applied to the micro‐hot plate, causing in‐situ heat‐up to reach 600°C for 30 seconds. Moreover, benefiting from the advantage of discrete structure, the sensor exhibited consistent and stable response characteristics even after undergoing more than 10 consecutive regeneration cycles, and the replaceable micro‐hotplate could further extend the service life of the sensor. These results show that the discrete AlGaN/GaN HEMT sensor can be a promising soot particulate sensing platform for automotive exhaust systems.

Small scale model for predicting transportation-induced particle formation in biotherapeutics

Understanding protein adsorption and aggregation at the air-liquid interfaces of protein solutions is an important open challenge in biopharmaceutical, medical, and biotechnological applications, among others. Proteins, being amphiphilic, adsorb at the surface, partially unfold, and form a viscoelastic film through non-covalent interactions. Mechanical agitation of the surface can break this film up, releasing insoluble protein particles into the solution. These aggregates are usually highly undesirable and even toxic in cases, such as for biopharmaceutical application. Therefore, it is imperative to be able to predict the behavior of such solutions undergoing surface agitation during handling, usually transport or mixing. We apply the findings on the viscoelastic protein film, formed at the air-liquid interface, to the prediction of surface mediated aggregation in selected protein solutions of direct biopharmaceutical relevance. Our broad study of Brewster angle microscopy and aggregation monitoring across multiple size ranges by micro-flow imaging, light scattering, and size exclusion chromatography shows that formation of protein particles is driven by the adsorption rate as compared to the rate of surface turnover and that surface film dynamics in the quiescent phase directly affect aggregation. We demonstrate how these learnings can be directly applied to the design of a novel small scale biopharmaceutical stability study, simulating relevant transport conditions. More generally, we show the impact of adsorption dynamics at the air-liquid interface on the stability of a distinct protein solution, as a general contribution to understanding different colloidal and biological interfacial systems.

Porosity Regulation of Surfactant‐Assisted Glycerol Organosolv Lignin Modified Hyper‐Cross‐Linked Polymers and Their Efficient Adsorption for Dyes From Water

ABSTRACTHere, we tried to use the natural biomass resources (lignin) to modify porous organic polymers (POPs) and expected to reduce the preparation cost and enhance the adsorption performance. Specifically, the surfactant‐assisted glycerol organosolv lignin (saGO lignin) was used as the modified agents to prepare lignin modified hyper‐cross‐linked polymers (LHCPs) by the copolymerization and Friedel‐Crafts reaction. We investigated the effect of synthesis conditions (the types and dosages of crosslinkers, the feeding amount of lignin, and so on) on the structure and adsorption performance of LHCPs. The results showed that divinyl benzene (DVB) crosslinked LHCP‐D (1041.3 m2/g) showed higher specific areas (SBET) than N,N′‐methylene diacrylamide (MBA) crosslinked LHCP‐M (183.1 m2/g), and the SBET had a certain increase with increasing the amount of DVB. Intriguingly, the SBET and micropore volume (Vmicro) of LHCPs appeared a linear decrease with the increase of lignin dosage, meanwhile, their morphology had a change from irregular block to agglomerated spherical particles, indicated their porosity and morphology can be well controlled. The Rhodamine B (RhB) adsorption experiments indicated that these LHCPs possessed fast adsorption rate (equilibrium time < 240 min) and good recycling performance, especially, LHCP‐D (lignin of 0.5 g, DVB of 1.0 g, catalyst of 3.0 g, reaction time of 10 h) showed the ultrahigh adsorption capacity, up to 743.7 mg/g. The adsorption mechanism was preliminarily investigated by X‐ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and adsorption models analysis, we found that the physical adsorption played the dominated roles by the π–π interaction, hydrogen bonding, and electrostatic interaction. This work not only offered an important reference for the high‐value utilization of lignin, but also provided an effective sustainable adsorbent for environmental remediation.

Microscopic Phage Adsorption Assay: High-throughput quantification of virus particle attachment to host bacterial cells.

Phages, viruses of bacteria, play a pivotal role in Earth's biosphere and hold great promise as therapeutic and diagnostic tools in combating infectious diseases. Attachment of phages to bacterial cells is a crucial initial step of the interaction. The classic assay to quantify the dynamics of phage attachment involves co-culturing and enumeration of bacteria and phages, which is laborious, lengthy, hence low-throughput, and only provides ensemble estimates of model-based adsorption rate constants. Here, we utilized fluorescence microscopy and particle tracking to obtain trajectories of individual virus particles interacting with cells. The trajectory durations quantified the heterogeneity in dwell time, the time that each phage spends interacting with a bacterium. The average dwell time strongly correlated with the classically-measured adsorption rate constant. We successfully applied this technique to quantify host-attachment dynamics of several phages including those targeting key bacterial pathogens. This approach should benefit the field of phage biology by providing highly quantitative, model-free readouts at single-virus resolution, helping to uncover single-virus phenomena missed by traditional measurements. Owing to significant reduction in manual effort, our method should enable rapid, high-throughput screening of a phage library against a target bacterial strain for applications such as therapy or diagnosis.

Effect of conditioners used for sludge dewatering on the adsorption performance of sludge-derived adsorbent

Converting waste activated sludge into adsorbent is a promising alternative for sludge valorization. While various conditioners are widely employed in sludge conditioning and dewatering processes, the influence of these conditioners on the properties of sludge derived adsorbents remains largely unexplored. Four conditioners, including FeCl3, CaO, polyacrylamide, FeSO4·7 H2O/Na2S2O8, were used for sludge conditioning, and the sludge dewaterability and the adsorption performance of the resultant adsorbents were evaluated. The sludge dewaterability was markedly improved by the conditioners in a descending order as polyacrylamide, FeCl3, FeSO4·7 H2O/Na2S2O8, and CaO. The type of conditioner highly influenced the adsorption ability of the sludge adsorbent: FeSO4·7 H2O/Na2S2O8 enhanced the adsorption ability, while others deteriorated it. Infrared spectra, pore size distribution, and micromorphology analysis of the adsorbents suggest that: FeCl3 reduced mesopores through strong electrostatic interactions; CaO acted as a physical barrier for adsorption; polyacrylamide reduced the adsorbent surface area through hydrogen bond-driven bridging and potentially forming polymeric barrier; FeSO4·7 H2O/Na2S2O8 disrupted the sludge flocs and exposed abundant adsorption sites, promoting the adsorbent performance markedly. FeSO4·7 H2O/Na2S2O8 conditioning was thus beneficial to both sludge dewatering and adsorption. Adsorption of methylene blue by FeSO4·7 H2O/Na2S2O8-conditioned sludge adsorbent was best described by the pseudo-second-order model and Langmuir model, indicating the dominance of monolayer chemisorption. The adsorption mainly occurred in the mesopores of the adsorbent, with hydroxyl group and carbonyl in carboxyl group as the main binding sites. Both film and pore diffusion contributed to the adsorption rate, with pore diffusion serving as the main rate limiting step. Results highlight the beneficial effect of destructive conditioning method on sludge adsorbent performance.