Contact Time Research Articles

Development of a wet digestion method for the analysis of metal soap in fat, oil, and grease deposits using the Taguchi method

Conventional methods for evaluating lipid-based metal salts in fats, oils and grease (FOG) deposits often fall short in assessing the efficiency of grease interceptors for food service establishment wastewater, primarily due to their inadequate specificity for fatty acid (FA) metal soaps. To address this issue, this study introduces a wet acid digestion method developed for the accurate analysis of metal soap content in FOG samples. The Taguchi experimental design method was used to determine the optimal conditions for digestion including temperature, contact time, solid/liquid ratio and type of acid mixture with the aim of more accurately quantifying metal salt concentrations. This work focused on identifying the most effective acid combinations for digesting FOG to enable analysis of commonly found metals. Extensive comparisons revealed that HNO3:H2SO4:H2O2 (1:2:1) and HNO3:H2O2 (1:3) were particularly effective at 180°C for 16h due to their significant oxidation potential. The HNO3:H2O2 (1:3) mixture yielded the highest concentrations of Ca, Mg, Na, and K of 296.38±0.66, 54.95±1.01, 247.65±2.27, and 46.09±3.44mg/g, respectively, aligning with the stringent optimisation principles of the Taguchi method. A one-way ANOVA test validated significant variances in metal contents (p < 0.005), and a t-test indicated a notably higher concentration of Ca compared to other metals. The study presents a sophisticated approach to evaluating the FA metal soap content of FOG ensuring enhanced accuracy and precision compared to established methods.

Development of the recording device to reduce an overlook of a defect for the impact acoustic method

Several concrete structures in Japan built during a period of high economic growth—including bridges (40%) and tunnels (25%)—are now at least 40 years old and are withering. Recent years have witnessed several accidents caused by falling concrete debris from these structures. To ensure safety, these buildings are regularly inspected with non-destructive tests such as the impact acoustic method (IAM). In this method, the surface of the concrete structure under inspection is impacted by a hammer and the resulting sound vibrations are used to detect defects. According to the current inspection standard, inspection records only contain information of detectable defects, because the method relies on the physical capabilities and expertise of the professional. Consequently, there are no records of imperceptible defects. In this study, we developed a recording device that consists of an accelerometer and a microphone and connected it to an impact hammer. The device saves the output from the two components in a single file. A set of concrete specimens were then tested using the IAM with the new device and hammer. Furthermore, the contact time and striking power of the hammer were estimated using a load sensor.

Patented Formulations, Nanotherapeutics and Herbal Compound Applications for Dry Eye : A Review

Background: The defining features of dry eye syndrome, a frequent tear and ocular surface multifactorial disorder, are changes in the ocular surface epithelia linked with less tear production and elevated sensitivity of the ocular surface, which trigger an inflammatory response. Aqueous deficit dry eye and evaporated dry eye are the two common types of dry eye. A few of the testing methods used to detect Dry Eye Disease are the Schirmer’s test, Tear Meniscus Volume, Tear Break-up Time, Tear Film Thickness, Meibomian Gland Infrared Meibography, Lissamine Green Staining, and Rose Bengal Staining. Hyperosmolarity and instability are the main pathogenic processes of dry eye disease. These systems are intricately linked to one another and create a "vicious circle" that never ends. Objective: The objective of this review was to describe patented formulations, novel drug delivery systems and herbal drugs for Dry Eye Disease. Results: Following a thorough assessment, the current study has elaborated a number of patented formulations in the form of contact lenses, biomarkers, novel approaches, and emulsions (traditional dosage forms) as well as natural medicines. In comparison to standard dosage forms, contact lenses and novel approaches have longer contact times and higher bioavailability. Conclusion: In this paper, the diagnostic methods of dry eye disease, the outcomes of pathophysiology, herbal treatments, nanotherapeutics, and current patented medicine formulations are described.

Efficient Removal of Pb(II) Ion Using Tio2/Zno/Sio2 Nanocomposite from Aqueous Solutions Via Adsorption-Photocatalysis Process

This research aims to investigate the usage of a TiO2/ZnO/SiO2 (TZS) composite prepared via a 24-h hydrothermal process at 180° C to remove Pb(II) through adsorption-photocatalysis. Pb(II) exposure has known health risks, making this study significant. The research explores the impact of pH, the nanocomposite quantity, and contact time in the process. Adsorption-photocatalysis was carried out in the dark for 60 min, followed by irradiation with a 160-watt mercury lamp. The adsorption process of Pb(II) ion removal adhered to the pseudo-second-order model regarding kinetics, while the adsorption isotherm corresponded to the Freundlich isotherm. Additionally, the assessment of photocatalysis kinetics showed that the removal of Pb(II) ions followed a pseudo-first-order model, resulting in a 99.58% elimination of Pb(II) ions. Post-adsorption-photocatalytic treatment, a yellowish precipitate was observed. The XRD pattern result of the yellowish precipitate confirmed the presence of PbO as the formed Pb phase. The study concludes that the TiO2/ZnO/SiO2 nanocomposite as adsorbent-photocatalyst is a highly effective, efficient, and promising method to remove Pb(II) contamination from aqueous solutions.

Adsorption of Heavy Metal from Wastewater by Bioabsorbent Modified Azolla microphylla and Lemna minor

Environmental toxicity from rapid industrialization raises concerns about water pollution caused by industrial waste and urban sewage. Aquatic macrophytes, such as the Azolla species, have shown promise in absorbing heavy metals and nutrients from water. This study introduces a novel approach by evaluating Azolla Microphylla and lemna minor as an economical adsorbent for copper removal from rivers. Moreover, this study stands out by conducting thorough characterization analyses. The adsorbent material underwent XRD, SEM, BET, and FTIR analyses after being crushed and sieved to 1-2 mm. Copper was extracted from river water using UV-Vis detection at 285 nm. Optimal conditions for adsorption were determined at pH 4, 30 minutes of contact time, and 0.4 g of adsorbent. Copper concentrations in the Sungai Petani, Sungai Selangor, and Sungai Langat ranged from 2 mgL-1 to 5 mgL-1. Azolla proves effective as a copper adsorbent due to its simplicity in sample preparation, time-saving benefits, cost-effectiveness compared to conventional systems, and high copper recovery rate. By successfully removing copper, a prevalent heavy metal contaminant in industrial waste and urban sewage, this research contributes to achieving Sustainable Development Goal 6 for clean and safe water supplies.

Evaluating the effectiveness of heavy metals removal from mine wastewater using agricultural waste materials

Polluted water bodies pose a danger to both aquatic and terrestrial lives, and recent development in the mining centre has escalated this pollution through the disposal of its industrial wastes. The objective was to investigate the potential of four different agricultural waste materials in eliminating the heavy metals from mine wastewater. The results show that the best performance in terms of adsorption capacity and removal efficiency was observed with coconut husk-activated carbon. The Arsenic (As) concentration decreased from 3.185 mg/kg to 1.570 mg/kg, and the Mercury (Hg) content decreased from 0.0307 mg/kg to 0.0064 mg/kg. The corresponding removal efficiencies were 51% for Arsenic and 79% for Mercury after 120 minutes of contact time at a speed of 250 rpm. The results suggest that coconut husk-activated carbon exhibited superior adsorption capacity and removal efficiency compared to the other agricultural waste materials (maize cob, rice husk, and sawdust). This indicates that the natural properties of coconut husk are more effective in removing heavy metals from mine wastewater.

Chitosan/Graphene oxide/SiO2 Nanoadsorbents for the Removal of Cr(VI) from Wastewaters

The swift industrialization and urbanisation have led to the discharge of significant amounts of hazardous heavy metals into water environments. Heavy metal pollution is currently one of the most significant environmental challenges being addressed, attracting researchers due to its biotoxicity, and non-biodegradability even at minimal concentrations [1]. Chromium (Cr) is among the most prevalent heavy metal contaminants. Its oxidation state, Cr(VI), harms the environment yet has catastrophic consequences for human health [2]. It is removed by physical and chemical procedures such as ion exchange, chemical precipitation and electrochemical treatment. Yet, most of these procedures have downsides, such as the formation of hazardous sludge, causing disposal issues and the need for costly tools and monitoring systems [3]. Adsorption is regarded an appealing and favourable technology because to its ease of design, simplicity, and high efficiency. Carbon-based nanomaterials have been investigated as superior adsorbents in aqueous solutions for the separation of organic and inorganic contaminants. The current study recommends the usage of adsorbents based on graphene oxide (GO). GO is an oxygen-rich material that is produced during the oxidation of graphite. It features hydrophobic areas due to aromatic groups in the nanosheets' centres, along with a large number of hydrophilic functional groups such as hydroxy, aldehyde, epoxy, and carboxyl groups [4]. The latter allow GO to swell and perform electrostatic functions. Chitosan (Cs) is a great adsorbent since it is inexpensive, is biocompatible, and causes no secondary pollution. Its molecular chains include -NH2 and -OH groups, which can interact with heavy metal ions and give significant adsorption capacity [5]. Silicon dioxide (SiO2) nanoparticles with graphene oxide have better physical and chemical characteristics than graphene oxide-like surface area. Similar research has revealed that the presence of SiO2 increases the adsorbent's adsorption capacity for Cr(VI) [6]. The effect of the pH value, contact time and initial chromium concentration was examined in order to determine the feasibility of Cs/GO@SiO2. Its structure and the morphology were studied in detail by the application of BET, XRD, FTIR and SEM techniques. According to the results, the modification of Cs with GO@SiO2 enhanced the percentage removal of chromium ions, especially, in acidic conditions by using 0.5 g/L of the adsorbent. Experimental data of equilibrium were used to calculate adsorption isotherms. According to thermodynamics the spontaneous nature of their adsorption was confirmed. Overall, the results indicate that Cs/GO@SiO2 can be effectively employed for removal of chromium from aqueous solutions.

Azine Based Oligoesteric Chemosensors for Cu2+ Ion Detection: Synthesis, Structural Characterization, and Theoretical Investigations.

Synthesized monomer and its three oligoesters were characterized by techniques such as 1H, 13C{1H}, IR, UV, GPC and applied to chemosensor applications. A series of metal ions was studied with fluorophores to evaluate the sensitivity towards Cu2+ ion. The fluorophores results exhibit the selective and sensitive "Turn off" fluorescence response with Cu2+ ion in DMF/H2O (1:1, pH: 7.4, fluorophore: 5µM) solution. Binding stoichiometry and binding constant of fluorophores were calculated using Stern-Volmer equation and Benesi-Hildebrand plots, respectively. Structure of fluorophores were studied using DFT, B3LYP/6-311 + + G(d,p) level basis set. Quenching mechanisms and electrical properties of fluorophores were explained with theoretical outcomes. Iodine doped and undoped oligoesters electrical conductivity were studied in solid-state and the conductivity was gradually increased with increase the contact time of iodine with oligoesters. At different frequencies and temperatures, the dielectric measurement was calculated using the two-probe method. Among all oligoesters, DMDAP exhibited high electrical conductivity and DMDMP has a higher dielectric constant value than other oligoesters.

Response surface methodology directed modeling of the biosorption of progesterone onto acid activated Moringa oleifera seed biomass: Parameters and mechanisms

In this study, chemically activated fat-free powdered Moringa oleifera seed biomass (MOSB) was synthesized, characterized, and utilized as a cost-effective biosorbent for the abstraction of progesterone (PGT) hormone from synthetic wastewater. Natural PGT is a human steroid hormone from the progestogen family. Synthetic PGT is approved for the regulation of the menstrual cycle, aiding contraception, and is administered as a hormone replacement therapy in menopausal and post-menopausal women. PGT is an endocrine disrupting chemical (EDC) with negative health impacts on biota. The X-ray diffractogram (XRD), Scanning electron microscopy-Energy-dispersive X-ray spectroscopy (SEM-EDS), and Brunauer–Emmet–Teller (BET) analyses displayed a porous, amorphous biosorbent with an elemental composition of 72.5% carbon and 22.5% oxygen and a specific surface area of 210.0 m2 g−1. The process variables including temperature (298–338 K), pH (2–10), contact time (10–180 min), adsorbate concentration (20–500 μg L−1), and adsorbent dosage (0.1–2.0 g) were optimized using response surface methodology (RSM) to obtain the greatest efficacy of MOSB during biosorption of PGT. The optimum parameters for PGT biosorption onto MOSB were: 86.8 min, 500 μg L−1 adsorbate concentration, 298 K, and 0.1 g adsorbent dosage. PGT removal from aqueous solutions was pH-independent. The Langmuir isotherm best fitted the equilibrium data with maximal monolayer biosorption capacity of 135.8 μg g−1. The biosorption rate followed the pseudo-first-order (PFO) kinetic law. The thermodynamic functions (ΔG < 0, ΔH = −9.258 kJ mol−1 and ΔS = +44.16 J mol−1) confirmed that the biosorption of PGT onto MOSB is a spontaneous and exothermic process with increased randomness at the adsorbent surface. The biosorption mechanism was physisorption and was devoid of electrostatic interactions. The findings from this study indicate that MOSB is an inexpensive, low-carbon, and environmentally friendly biosorbent that can effectively scavenge PGT from aqueous solutions.

Nickel−manganese−cobalt tetragonal spinel ternary oxide nanocomposite as an effective adsorbent for dispersive solid phase micro-extraction of cadmium in food and water samples

Nickel−manganese−cobalt tetragonal spinel ternary oxide nanocomposite (NMC-TSO) was synthesized. It was utilized as an efficient sorbent for the dispersive solid phase microextraction (D-SPμE) without vortexing of cadmium. The analysis of the cadmium was carried out by FAAS. The effective analytical parameters including pH (6) contact times (no vortexing), sample volume (70 mL), eluent volume (3 mL of 2 mol L−1 HCl), linear dynamic ranges (1.07–85.7 μg L−1), and re-useability (33) on the D-SPμE efficiency were investigated. The PF, RSD% and LOD of the D-SPμE for cadmium were 23.3, ≤ 2.8% and 0.49 μg L−1, respectively. The tolerable concentrations of Ca2+, Mg2+, K+ and Na+ on Cd(II) were 50,000 mg L−1, 50,000 mg L−1, 25,000 mg L−1 and 7500 mg L−1, respectively. The method was accurated by analysis of food and water certificate reference materials (NW-TMDA-54.6 Lake water, SPS-WW1 121 Batch wastewater, 1573a Tomato Leaves and TORT-3 Lobster Hepatopancreas) and - recovery experiments. The D-SPμE-FAAS method was applied for the cadmium determination in dam water, wastewater, river water, well water, sea water, tea, cacao, nut, bitter chocolate, rice, leek, cinnamon and parsley.

Optimization of batch process parameters for chromium (VI) removal from synthetic wastewater using eggshell–clay composite

In this study, a biodegradable spherical adsorbent bead was developed from eggshell (ES) and Bijoypur clay (BC) for the removal of hexavalent chromium from synthetic tannery wastewater. This Eggshell–Clay polymer composite (ES–BC) was made by incorporating them with PVA and alginate. To analyze the morphology and chemical composition of the adsorbent before and after the chromium adsorption, SEM, FTIR, XRD, and EDX were used. The impact of adsorption parameters such as adsorbent dosage (0.67–2.23 g/L), pH of the solution (1.5–9), contact time (10–240 min), initial Cr (VI) concentration (25–100 ppm), and solution temperature (25–65 °C), percentage clay in ES-BC adsorbent (0–40%) for Cr (VI) adsorption were investigated. The optimum value for adsorbent dosage, pH, contact time, initial Cr concentration, temperature, and clay to eggshell ratio was found 1.17 g/L, 1.5, 150 min, 58.2 ppm, 25 °C, and 80/20% respectively. The isotherm model was well-fitted to the Freundlich isotherm suggesting heterogeneous adsorption in multilayer on surface. The adsorption kinetics followed pseudo-second-order kinetics supporting the chemisorption process. Moreover, a decrease in enthalpy (H°) and negative Gibbs free energy (G°) with increased temperature indicated exothermic and spontaneous reaction. Therefore, this research investigated that the composite may serve as a viable option for treating Cr (VI) containing tannery effluent.

Modelling and optimising the performance of graphene oxide-Cu2SnS3-polyaniline nanocomposite as an adsorbent for mercury ion removal.

Finding a cost-effective, efficient, and environmentally friendly technique for the removal of mercury ion (Hg2+) in water and wastewater can be a challenging task. This paper presents a novel and efficient adsorbent known as the graphene oxide-Cu2SnS3-polyaniline (GO-CTS-PANI) nanocomposite, which was synthesised and utilised to eliminate Hg2+ from water samples. The soft-soft interaction between Hg2+ and sulphur atoms besides chelating interaction between -N and Hg2+ is the main mechanism for Hg2+ adsorption onto the GO-CTS-PANI adsorbent. Various characterisation techniques, including Fourier transform infrared spectrophotometry (FT-IR), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), elemental mapping analysis, and X-ray diffraction analysis (XRD), were employed to analyse the adsorbent. The Box-Behnken method, utilising Design Expert Version 7.0.0, was employed to optimise the crucial factors influencing the adsorption process, such as pH, adsorbent quantity, and contact time. The results indicated that the most efficient adsorption occurred at pH 6.5, with 12mg of GO-CTS-PANI adsorbent, and 30-min contact time that results in a maximum removal rate of 95% for 50mg/L Hg2+ ions. The study also investigated the isotherm and kinetics of the adsorption process that the adsorption of Hg2+ onto the adsorbent happened in sequential layers (Freundlich isotherm) and followed by the pseudo-second-order kinetic model. Furthermore, response surface methodology (RSM) analysis indicates that pH is the most influential parameter in enhancing adsorption efficiency. In addition to traditional models, this study employed some artificial intelligence (AI) methods including the Random Forest algorithm to enhance the prediction of adsorption process efficiency. The findings demonstrated that the Random Forest algorithm exhibited high accuracy with a correlation coefficient of 0.98 between actual and predicted adsorption rates. This study highlights the potential of the GO-CTS-PANI nanocomposite for effectively removing of Hg2+ ions from water resources.

Carboxymethyl-imidazolium O-vanillin Schiff base grafted into NH2-tagged MIL-101 (Cr) for effective removal of cupric ions from aqueous effluents.

A novel adsorbent (MIL-CMIVSB) was fabricated by modification of H2N-MIL-101(Cr) with carboxymethyl-imidazolium O-vanillin Schiff base. The MIL-CMIVSB's physicochemical characteristics were examined using the pertinent characterization methods. NH2-MIL-101(Cr) has a BET surface area of 1492.4 m2g-1, while MIL-CMIVSB adsorbent had 1278.7 m2g-1. Batch adsorption experiments examined the MIL-CMIVSB's cupric ion adsorption capacity from aqueous solutions at different adsorbent doses (0.1-3mg), pH (2.0-10.0), contact times (0-240min), metal ion initial concentrations (10-300mg/L), and temperatures (298-308K). The optimum conditions were 1mg/mL of MIL-CMIVSB adsorbent, 46min adsorption time, pH 7, 100ppm initial cupric ion concentration, and 303K temperature. MIL-CMIVSB effectively and selectively removes cupric ions with an adsorption capability of 359.05 ± 12.06mg/g. The nonlinear Liu isotherm governed Cu(II) sorption performance on MIL-CMIVSB (KL = 0.257 ± 0.01mg/g, R2 = 0.99892) and pseudo-2nd-order kinetically (k2 = 0.00116 × 10-4g/mg min, R2 = 0.99721).

Aerosol trace element solubility determined using ultrapure water batch leaching: an intercomparison study of four different leaching protocols

Abstract. Solubility of aerosol trace elements, which determines their bioavailability and reactivity, is operationally defined and strongly depends on the leaching protocol used. Ultrapure water batch leaching is one of the most widely used leaching protocols, while the specific leaching protocols used in different labs can still differ in agitation methods, contact time, and filter pore size. It is yet unclear to which extent the difference in these experimental parameters would affect the aerosol trace element solubility reported. This work examined the effects of agitation methods, filter pore size, and contact time on the solubility of nine aerosol trace elements and found that the difference in agitation methods (shaking vs. sonication), filter pore size (0.22 vs. 0.45 µm), and contact time (1 vs. 2 h) only led to small and sometimes insignificant difference in the reported solubility. We further compared aerosol trace element solubility determined using four ultrapure water leaching protocols, which are adopted by four different labs and vary in agitation methods, filter pore size, and/or contact time, and observed good agreement in the reported solubility. Therefore, our work suggests that although ultrapure water batch leaching protocols used by different labs vary in specific experimental parameters, the determined aerosol trace element solubility is comparable. We recommend that ultrapure water batch leaching be one of the reference leaching schemes and emphasize that additional consensus in the community on agitation methods, contact time, and filter pore size is needed to formulate a standard operating procedure for ultrapure water batch leaching.

Recycling of sludge residue as a coagulant for phosphorus removal from aqueous solutions.

Phosphorus pollution poses a significant challenge in addressing water contamination. The coagulant is one of the effective methods to remove phosphorus from wastewater. Abundant Al and Fe oxides in sludge residue make it have great potential to synthesize water treatment coagulants. However, the utilization of sludge residue for preparation of coagulant was seldom investigated. In this study, we fabricated a novel coagulant, polyaluminum ferric chloride (SM-PAC), using sludge residue as a raw material through acid leaching and polymerization processes. Characterization results confirm that the parameters of SM-PAC meet the specifications outlined in the national standard (GB/T 22627-2022). We investigated the effects of pH, dosage, initial phosphorus concentration, and contact time on the removal efficiency of SM-PAC. As anticipated, the prepared SM-PAC exhibited a significant efficacy in removing phosphorus, meeting the discharge standards set for municipal sewage. Furthermore, the adsorption kinetics analysis suggests that the predominant mode of phosphorus adsorption on SM-PAC is chemical adsorption. Furthermore, the SM-PAC was employed in the actual wastewater treatment plant and exhibited excellent efficiency in phosphorus removal. The utilization of SM-PAC can not only effectively address the issue of sludge disposal but also achieve the goal of "treating waste with waste." It is expected that the proposed method of reusing sludge residue as a resource can provide a sustainable way to synthesize a coagulant for phosphorus removal.

Poly(aniline‐co‐pyrrole) as Adsorbent for Removal of Pharmaceuticals: Preparation, Characterization, Kinetics, Isotherms and Application on Sample Preparation

AbstractHerein, poly(aniline‐co‐pyrrole) has been synthetized and investigated to adsorb phenylbutazone (PBZ), ceftiofur (CEF) and prednisolone (PRD) in aqueous medium as proof of concept. After proper adsorbent characterization, some studies were carried out in batch process, i. e., contact time, pH, and concentration. The adsorption mechanism has been conducted using kinetic and isothermal models. It was found that the reaction equilibrium was reached in 20 min for all analytes. The best fit for the experimental data were obtained employing the models of dual‐site Langmuir–Freundlich, Fritz–Schlunder and Langmuir, with R2=0.999, 0.952 and 0.974, for PBZ, CEF and PRD, respectively. For PBZ, CEF and PRD, poly(aniline‐co‐pyrrole) provided a Qmax=238.8 mg g−1 and Kmax=0.086 L g−1, Q=0.028 mg g−1 and Kmax=3.258 L g−1, Q=13.66 mg g−1 and KL=0.005 L g−1, respectively. Finally, the copolymer was evaluated in solid phase extraction, which showed recovery around 70 % for PBZ, offering also exciting opportunities for further application in the separation process.

Adsorption of Pb, Cu, and Ni Ions on Activated Carbon Prepared from Oak Cupules: Kinetics and Thermodynamics Studies

Agricultural residue-activated carbon and biochar, inexpensive and environmentally friendly adsorbent materials, have recently received significant research attention. This study investigated the potential use of oak cupules in activated carbon form to remove widespread heavy metals (Pb2+, Cu2+, and Ni2+) from wastewater. The oak-activated carbon was prepared from oak cupules and activated with phosphoric acid. Oak-activated carbon was characterized using FTIR, BET analysis, energy-dispersive X-ray spectrometry (EDS), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The Freundlich, Langmuir, and Temkin isotherm models were used to assess the equilibrium data. The impact of various parameters, including pH effect, temperature, adsorbent dose, and contact time, was estimated. The Freundlich model was the most agreeable with Pb2+ adsorption by oak-based activated carbon, and Langmuir was more compatible with Cu+2 and Ni+2. Under optimum conditions, the average maximum removal was 63% Pb2+, 60% Cu2+, and 54% Ni2+ when every ion was alone in the aqueous solution. The removal was enhanced to 98% Pb2+, 72% Cu2+, and 60% Ni2+ when found as a mixture. The thermodynamic model revealed that the adsorption of ions by oak-based activated carbon is endothermic. The pseudo-second-order kinetic best describes the adsorption mechanism in this study; it verifies chemical sorption as the rate-limiting step in adsorption mechanisms. The oak-activated carbon was effective in removing Pb2+, Cu2+, and Ni2+ from wastewater and aqueous solutions.

Physiologist-led management of heart failure patients using cardiac implantable electronic device diagnostics during COVID-19: a 2-year UK perspective

Abstract Background/ Introduction The COVID-19 pandemic prompted greater use of remote monitoring capabilities of cardiac implantable electronic devices (CIED). The HeartLogic Index incorporated within certain Boston Scientific CIEDs uses device-derived physiological parameters to generate a score which may be predictive of worsening heart failure (HF). We aimed to define the utility of a novel service, led by cardiac physiologists acting autonomously upon HeartLogic Index alerts, to guide HF patient care during the pandemic. Purpose To assess the utility of a physiologist-led HF service, using CIED diagnostics combined with clinical assessment, to improve HF management. Methods In a single-centre prospective study, 153 Boston Scientific CRT/ICD patients were reviewed over a 2-year period using the integrated HeartLogic algorithm. In response to a HeartLogic alert indicating worsening HF, the patient was contacted by a cardiac physiologist using a structured telephone triage to assess HF symptoms. In those deemed as being at risk of decompensated HF based on clinical assessment, an intervention was made e.g. face-to-face physiologist-led clinical assessment, consultant review, medication optimisation. Results During the 2-year audit, 748 alerts were received from 60 patients, the majority of which had a HF implant indication (n=42). Twenty-one patients within the study population required an intervention due to worsening HF. Following intervention, there were no further hospitalisations within this group. Five hospitalisations were documented during the audit, only 3 of which were HF related. Of these HF hospitalisations, one patient denied HF symptoms at the time of telephone contact, one had a HF decompensation due to deteriorating renal failure and the final patient had a disconnected remote monitor. During the 2-year audit, there were a total of 13 deaths, 3 of which were classified as caused by HF. Conclusion A physiologist-led service may be of clinical utility within this complex patient population, with the audit results demonstrating favourable outcomes with a low rate of mortality and HF hospitalisations. The addition of this service can act to streamline the time from patient presentation to HF review, and therefore improve patient care.

CuFeS2/MXene-Modified Polyvinylidene Fluoride Membrane for Antibiotics Removal through Peroxymonosulfate Activation

In this research, the CuFeS2/MXene-modified polyvinylidene fluoride (PVDF) membrane was prepared to activate peroxymonosulfate (PMS) to remove moxifloxacin (MOX) and its morphology; surface functional groups and hydrophilicity were also studied. The parameters of the catalytic membrane/PMS system were optimized, with an optimal loading of 4 mg/cm2 and a PMS dosage of 0.20 mM. High filtration pressure, alkaline conditions, and impurities in water could inhibit MOX removal. After continuous filtration, the removal efficiency of MOX using the catalytic membrane/PMS system and PVDF membrane was 68.2% and 9.9%, respectively. Batch filtration could remove 87.8% MOX by the extra 10 min contact time between the catalytic membrane and solution. During the filtration process, CuFeS2/MXene on the surface of the catalytic membrane activated PMS to produce SO4•−, HO•, and 1O2, and MOX was removed through adsorption and degradation. Taking humic acid (HA) as the model foulant, reversible fouling resistance in the catalytic membrane/PMS system was 22.8% of the PVDF membrane. The catalytic membrane/PMS system weakened the formation of the cake layer by oxidizing HA into smaller pollutants and followed the intermediate blocking cake filtration model. The novelty of this research was to develop a CuFeS2/MXene–PVDF membrane-activated PMS system and explore its application in antibiotics removal.

Removal of carcinogenic chromium(VI) from effluent of electroplating industry using adsorptive separation

AbstractThe wastewater from an electroplating industry contains chromium VI which is highly carcinogenic at a typical level of 21.5 to 47 mg L−1 which should be reduced to acceptable value of 0.05 mg L−1 for the water to be suitable for drinking purpose. In this study, Tulsion A23 resin was applied as an adsorbent for successful removal of Cr(VI), also dealing with understanding the effect of various parameters on extent of removal of the contaminant. It was elucidated that contact time of 120 min is required for the equilibrium and the optimum pH value was 5 and the optimum resin loading was 4 g L−1 at which 97% Cr(VI) removal was observed. Different adsorption isotherm models were applied and it was elucidated that Langmuir model was the best fit with R2 as 0.99. In the case of kinetic study, pseudo‐second order model was best fitted with higher R2 value. The regeneration of the resin was performed using 3 M NaOH and it was shown that after the three cycles of regeneration, the resin showed 82% Cr(VI) removal. Overall, successful application of Tulsion A23 resin was demonstrated for the removal of Cr(VI) from real effluent for the first time.