Access to natural green spaces and their associations with psychological wellbeing for South Asian people in the UK: A systematic literature review.

Use of natural green spaces (NGS) is associated with improved psychological well-being (PWB). Ethnic minorities, particularly South Asian (SA) communities in the UK, face unequal access to NGS and experience a greater prevalence of health challenges than the general population. Improving access to green space can contribute to addressing current health inequalities. Following PRISMA guidelines, this systematic literature review aimed to synthesise existing research on NGS access barriers experienced by SAs and associations between NGS use and PWB. A comprehensive search was conducted through SAGE, Science Direct, and SCOPUS in August 2022; we included qualitative, quantitative and mixed-methods studies with findings on NGS access and/or associations between NGS use and PWB for SAs in the UK. We employed deductive thematic analysis to explore inhibitors and enablers of access which were then conceptualised through a multidimensional framework. Associations between NGS and PWB were coded inductively and mapped separately. This review is registered on PROSPERO: CRD42022353711. Twenty-six studies were included in the review which varied substantially in their aims, methods, context, and participants. Included studies on NGS grouped SAs within broader demographic categories such as minority ethnic communities or Muslims. Our findings indicate that SAs are disadvantaged in their access to NGS due to numerous intersecting factors including unequal distribution, inadequate transport, racialisation of NGS, and safety concerns. Whilst these findings generally aligned with broader literature on NGS access, certain access barriers and enablers are particularly significant to SA communities. We also identified several dimensions of PWB that are enhanced for SAs through interacting with NGS including overall mental health outcomes, physical wellbeing, and social relatedness. This review highlights opportunities to improve access to NGS and thereby enhance PWB outcomes for SA people. It also identifies the lack of primary research exploring NGS access and PWB associations for SA communities, specifically in rural contexts.

A new strategy to construct MOF-on-MOF derivatives for the removal of tetracycline hydrochloride from water by activation of peroxymonosulfate.

A MOF-on-MOF composite derivative material named ZIF-67@Ce-MOF-600 was designed and synthesized. The preparation of ZIF-67@Ce-MOF-600 was optimized from the aspects of the ratio of metal and ligand, heat-treatment temperature. It was demonstrated by XRD, FT-IR, SEM-EDS and TEM. The optimum conditions for the activation of PMS by ZIF-67@Ce-MOF-600 for the degradation of tetracycline (TC) were investigated by adjusting the catalyst dosage, TC, pH, peoxymonosulfate (PMS) concentration, and different kinds of water, co-existing anions and pollution. Under optimal conditions (20 mg catalysts and 50 mg PMS added) in 100 mL of tetracyclines (TC) solvent (20 mg TC/L), the removal rate could reach up to 99.2% and after five cycles was 70.5%. The EPR results indicated the presence of free radicals and non-free radical, among which free radicals intended to play a major role in the degradation process. Its possible degradation pathways and attack sites were analyzed by liquid-phase mass spectrometry and DFT analysis.

Study of the Adsorption and Separation Behavior of Scandium and Zirconium by Trialkyl Phosphine Oxide-Modified Resins in Sulfuric and Hydrochloric Acid Media.

Zirconium is recognized as one of the main impurities of the rare earth element scandium during purification. It presents significant challenges due to its similar chemical properties, making separating it difficult. This study used trialkyl phosphine oxide (TRPO) as a functional ligand, and the effects of carrier type and acidity on adsorption performance were first investigated. Among these, the novel extraction resin SiO2-P as a carrier for TRPO demonstrated more prominent separation performance in 0.2 M H2SO4 and 5 M HCl solutions. The kinetic and isotherm data were consistent with the pseudo-secondary kinetics and Langmuir model, respectively, and the adsorption process could be regarded as homogeneous monolayer adsorption subject to the dual effects of chemisorption and internal diffusion. In addition, thermodynamic analysis showed that the adsorption process of zirconium under the experimental conditions was a spontaneous endothermic process. Combined with the results of SEM-EDS, FT-IR, and XPS analyses, scandium and zirconium were successfully adsorbed by the resin and uniformly distributed on its surface, and the greater affinity of the P=O groups on the resin for zirconium was the critical factor contributing to the separation of scandium and zirconium. Finally, scandium and zirconium in sulfuric acid and hydrochloric acid media were extracted and separated by column experiments, and the purity of scandium could reach 99.8% and 99.99%, respectively.

Exploring the Antimicrobial, Antioxidant, and Antiviral Potential of Eco-Friendly Synthesized Silver Nanoparticles Using Leaf Aqueous Extract of Portulaca oleracea L.

Herein, the prospective applications of green fabricated silver nanoparticles (Ag-NPs) within the biomedical field were investigated. The leaf aqueous extract of Portulaca oleracea L., a safe, cheap, and green method, was used to fabricate Ag-NPs. The maximum plasmon resonance of synthesized NPs has appeared at 420 nm. The various biomolecules present in the plant extract to assemble spherical Ag-NPs with sizes of 5-40 nm were analyzed using Fourier transform infrared and transmission electron microscopy. The Ag was the major content of the formed Ag-NPs with an atomic percent of 54.95% and weight percent of 65.86%, as indicated by EDX. The crystallographic structure of synthesized NPs was confirmed by the diffraction of the X-ray. The dynamic light scattering exhibits the homogeneity and mono-dispersity nature with a polydispersity index of 0.37 in the colloidal fluid and a zeta potential value of -36 mV. The synthesized Ag-NPs exhibited promising antimicrobial efficacy toward various prokaryotic and eukaryotic pathogenic microorganisms with low MIC values of 12.5 µg mL-1 and 6.25 µg mL-1, respectively. Additionally, the P. oleracea-formed Ag-NPs showed optimistic antioxidant activity assessed by DPPH and H2O2 assay methods with the highest scavenging percentages of 88.5 ± 2.3% and 76.5 ± 1.7%, respectively, at a concentration of 200 µg mL-1. Finally, the biosynthesized Ag-NPs showed high antiviral properties toward the hepatitis A virus and Cox-B4 with inhibition percentages of 79.16 ± 0.5% and 73.59 ± 0.8%, respectively. Overall, additional research is essential to explore the Ag-NP-based aqueous extract of P. oleracea for human health. In the current investigation the use of synthesized Ag-NPs as antimicrobial, antioxidant, and antiviral agents to protect against pathogenic microbes, degenerative diseases caused by various oxidative stresses, and deadly viruses is recommended.

Novel phosphate functionalized sodium alginate hydrogel for efficient adsorption and separation of Nd and Dy from Co.

The recovery of rare earth elements (REEs) including neodymium (Nd) and dysprosium (Dy) from NdFeB permanent magnets has become one of the main ways to solve the increased demand for rare earth. Herein, n-dodecyl phosphate (DPPA) was used for the first time as the adsorption functional group donor, sodium alginate as the substrate, and calcium chloride solution as the reactive solvent, a hybrid hydrogel adsorbent DPPA/CaALG was synthesized by sol-gel method for application in the adsorption and separation of Nd and Dy from the Co-Nd-Dy ternary system. SEM-EDS, and N2 adsorption-desorption analysis showed the successful preparation of DDPA/CaALG with mesoporous structure. Batch experiments showed the superiority of the hybrid hydrogel for the good selective adsorption of Nd and Dy, such as large adsorption capacity (Nd: 162.5 mg/g, Dy: 183.5 mg/g), and no adsorption for Co. FT-IR, XPS showed that PO and P-O groups are involved in the adsorption process of Nd and Dy as electron acceptors, where the ion exchange of P-OH is dominant. Furthermore, the chemical properties of ligands and complexes were analyzed by Density Functional Theory (DFT) calculations and revealed their adsorption behaviors as well as the competition between different metal ions.

Phosphination of amino-modified mesoporous silica for the selective separation of strontium.

Radioactive strontium (90Sr) is considered as one of the most dangerous radionuclides due to its high biochemical toxicity. For the efficient and selective separation of Sr from acidic environments, a novel functional adsorbent CEPA@SBA-15-APTES was prepared in this work through the phosphorylation of amino-modified mesoporous silica with organic content of approximately 20 wt%. CEPA@SBA-15-APTES was characterized by TEM, SEM, EDS, TG-DSC, BET, FTIR, and XPS techniques, revealing its characteristics of an ordered hexagonal lattice-like structure and rich functional groups. The experimental results demonstrated that the adsorbent exhibited good adsorption capacity for Sr over a wide acidity range (i.e., from 10-10 M to 4 M HNO3). The adsorption equilibriums of Sr by CEPA@SBA-15-APTES in 10-6 M and 3 M HNO3 solutions were reached within 30 and 5 min, respectively, and the adsorption capacities at 318 K were 112.6 and 71.8 mg/g, respectively. Furthermore, by combining the experimental and characterization results, we found that the adsorption mechanism consisted of ion exchange between Sr(II) and H+ (in P-OH) in the 10-6 M HNO3 solution and coordination between the Sr(II) and oxygen-containing (CO and P = O) functional groups in the 3 M HNO3 solution.

Precise stepwise recovery of platinum group metals from high-level liquid wastes based on SDB polymer-modified SiO2.

Accurate separation and efficient recovery of platinum group metals (PGMs, mainly Ru, Rh and Pd) from high level liquid waste (HLLW) is a good choice for clean production and sustainable development of nuclear energy. Herein a novel SDB polymer modified silica-based amine-functionalized composite (dNbpy/SiO2-P) was synthesized for the separation and recovery of PGMs. Laser particle size analysis and BET results clarified the regular spherical and highly interconnected mesoporous structure of dNbpy/SiO2-P which is critical for the separation of PGMs. The removal percent of PGMs were over 99% on the optimized conditions. In addition, dNbpy/SiO2-P showed excellent selectivity (SFPd/M > 3805, SFRu/M > 1705, SFRh/M > 336) and repeatability (≥5). Interestingly, based on the different adsorption and desorption kinetics of PGMs, a double-column strategy is designed to solve the challenge of separating and recovering PGMs from HLLW. The enrichment factors of Pd(II), Ru(III) and Rh(III) reached 36.7, 8.2, and 1.2. The adsorption of PGMs was coordination mechanism and required the involvement of NO3- to maintain charge balance. The specific distribution of elements within the adsorbents and the changes in valence state were analyzed using depth-profiling XPS. Both depth-profiling XPS results and slope analysis revealed that the complex of dNbpy and PGMs is a 1 : 1 coordination structure. Overall, this work fills the gap that PGMs cannot be effectively separated and enriched from HLLW.

Precise recognition and efficient recovery of Pd(II) from high-level liquid waste by a novel aminothiazole-functionalized silica-based adsorbent.

Efficient recognition, separation and recovery of palladium from high-level liquid waste (HLLW) not only helps the safe, green and environmentally friendly disposal of nuclear waste, but also is an essential important supplement to overcome the growing shortage of natural palladium resources. Herein, a novel silica-based functional adsorbent named 2AT-SiAaC was prepared by a two-step method, i.e., grafting of 2-aminothiazole (2AT) via the amidated reaction after in-situ polymerization of acrylic monomers on porous silica. SEM, EDS, TG-DSC, BET and PXRD all proved the successful preparation of 2AT-SiAaC, and it exhibited ultrahigh adsorption selectivity for Pd(II) (Kd (distribution coefficient) ≥ 10,344.2 mL/g, SFPd/M (separation factor) ≥ 613.7), fast adsorption kinetics with short equilibrium time (t ≤ 1 h) and good adsorption capacity (Q ≥ 62.1 mg Pd/g). The dynamic column experiments shows that 2AT-SiAaC achieved efficiently separation of Pd(II) from simulated HLLW, and the enrichment coefficients (C/C0) of Pd(II) was as high as about 14 with the recovery rate nearly 99.9% and basically kept the same performance in three adsorption-desorption column cycle experiments. The adsorption mechanism was analyzed by FT-IR, XPS and DFT calculations, and the ultrahigh selectivity of 2AT-SiAaC was attributed to the preferred affinity of the soft N-donor atoms in 2AT for Pd(II). NO3- ions participated in the adsorption reaction to keep charge balance, and the frontier orbital electron density distribution diagram shows the charge transfer in the process of material preparation and adsorption. To sum up, 2AT-SiAaC adsorbent provided a new insight for precise recognition and efficient separation of Pd(II) from HLLW.

Robust memory humoral immune response to SARS-CoV-2 in the tonsils of adults and children.

Background: Adaptive humoral immunity against SARS-CoV-2 has mainly been evaluated in peripheral blood. Human secondary lymphoid tissues (such as tonsils) contain large numbers of plasma cells that secrete immunoglobulins at mucosal sites. Yet, the role of mucosal memory immunity induced by vaccines or natural infection against SARS-CoV-2 and its variants is not fully understood. Methods: Tonsillar mononuclear cells (TMNCs) from adults (n=10) and children (n=11) were isolated and stimulated using positive SARS-CoV-2 nasal swabs. We used endpoint enzyme-linked immunosorbent assays (ELISAs) for the measurement of anti-S1, -RBD, and -N IgG antibody levels and a pseudovirus microneutralization assay to assess neutralizing antibodies (nAbs) in paired serum and supernatants from stimulated TMNCs. Results: Strong systemic humoral response in previously SARS-CoV-2 infected and vaccinated adults and children was observed in accordance with the reported history of the participants. Interestingly, we found a significant increase in anti-RBD IgG (305 and 834 folds) and anti-S1 IgG (475 and 443 folds) in the stimulated TMNCs from adults and children, respectively, compared to unstimulated cells. Consistently, the stimulated TMNCs secreted higher levels of nAbs against the ancestral Wuhan strain and the Omicron BA.1 variant compared to unstimulated cells by several folds. This increase was seen in all participants including children with no known history of infection, suggesting that these participants might have been previously exposed to SARS-CoV-2 and that not all asymptomatic cases necessarily could be detected by serum antibodies. Furthermore, nAb levels against both strains were significantly correlated in adults (r=0.8788; p = 0.0008) and children (r = 0.7521; p = 0.0076), and they strongly correlated with S1 and RBD-specific IgG antibodies. Conclusion: Our results provide evidence for persistent mucosal humoral memory in tonsils from previously infected and/or vaccinated adults and children against recent and old variants upon re-exposure. They also highlight the importance of targeting mucosal sites with vaccines to help control infection at the primary sites and prevent potential breakthrough infections.

Visualization of Subcutaneous Blood Vessels Based on Hyperspectral Imaging and Three-Wavelength Index Images.

Blood vessel visualization technology allows nursing staff to transition from traditional palpation or touch to locate the subcutaneous blood vessels to visualized localization by providing a clear visual aid for performing various medical procedures accurately and efficiently involving blood vessels; this can further improve the first-attempt puncture success rate for nursing staff and reduce the pain of patients. We propose a novel technique for hyperspectral visualization of blood vessels in human skin. An experiment with six participants with different skin types, race, and nationality backgrounds is described. A mere separation of spectral layers for different skin types is shown to be insufficient. The use of three-wavelength indices in imaging has shown a significant improvement in the quality of results compared to using only two-wavelength indices. This improvement can be attributed to an increase in the contrast ratio, which can be as high as 25%. We propose and implement a technique for finding new index formulae based on an exhaustive search and a binary blood-vessel image obtained through an expert assessment. As a result of the search, a novel index formula was deduced, allowing high-contrast blood vessel images to be generated for any skin type.

Effect of the magnetic core in alginate/gum composite on adsorption of divalent copper, cadmium, and lead ions in the aqueous system.

The change of composition of an adsorbent material has been widely used as a method to increase its adsorption capacity, particularly concerning adsorbents made of polysaccharides. Introducing magnetic adsorbents into contaminated water treatment systems is a highly promising strategy, as it promotes the metal ions removal from water. Considering this, gum Arabic (GA) was associated with alginate (Alg), when magnetite nanoparticles were present or absent, to produce beads that were utilised to take up Cu(II), Cd(II), and Pb(II) from aqueous solution. After a complete characterisation (for which Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and swelling were used), the adsorption properties were established using batch and column tests. The magnetic beads (MAlg/GA) demonstrated improved adsorption in comparison with the beads made without magnetite (Alg/GA) under the same conditions. In normal adsorption conditions (pH 6.0, 25 °C, 2.5 g L-1 of adsorbent dosage), the highest uptake capacities recorded for the MAlg/GA beads were: for Cu(II), 1.33 mmol g-1; Cd(II), 1.59 mmol g-1; and for Pb(II), 1.43 mmol g-1. The pseudo-second-order kinetics and Langmuir isotherm models provided good fits for the adsorption of these metals. Overall, ion exchange and physical forces led to the uptake of these metals by both Alg/GA and MAlg/GA; moreover, the functional groups on the beads played crucial roles as binding sites. Additionally, it was observed that flow rates of >2 mL min-1 did not produce noticeable changes in uptake levels over the same flow period. It was found that the efficient eluting agent was HNO3 (0.2 M). In some cases, the metals were not removed fully from the used beads during the first five cycles of regeneration and reuse. The results of this investigation show that these beads are efficient adsorbents for the removal of metal ions from spiked well water samples.

Green Synthesis of Zinc Oxide Nanoparticles Using an Aqueous Extract of Punica granatum for Antimicrobial and Catalytic Activity.

The peel aqueous extract of Punica granatum was utilized to fabricate zinc oxide nanoparticles (ZnO-NPs) as a green approach. The synthesized NPs were characterized by UV-Vis spectroscopy, Fourier transform infrared (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy, which was attached to an energy dispersive X-ray (SEM-EDX). Spherical, well arranged, and crystallographic structures of ZnO-NPs were formed with sizes of 10-45 nm. The biological activities of ZnO-NPs, including antimicrobial and catalytic activity for methylene blue dye, were assessed. Data analysis showed that the antimicrobial activity against pathogenic Gram-positive and Gram-negative bacteria, as well as unicellular fungi, was observed to occur in a dose-dependent manner, displaying varied inhibition zones and low minimum inhibitory concentration (MIC) values in the ranges of 6.25-12.5 µg mL-1. The degradation efficacy of methylene blue (MB) using ZnO-NPs is dependent on nano-catalyst concentration, contact time, and incubation condition (UV-light emission). The maximum MB degradation percentages of 93.4 ± 0.2% was attained at 20 µg mL-1 after 210 min in presence of UV-light. Data analysis showed that there is no significant difference between the degradation percentages after 210, 1440, and 1800 min. Moreover, the nano-catalyst showed high stability and efficacy to degrade MB for five cycles with decreasing values of 4%. Overall, P. granatum-based ZnO-NPs are promising tools to inhibit the growth of pathogenic microbes and degradation of MB in the presence of UV-light emission.

Phosphonation of Alginate-Polyethyleneimine Beads for the Enhanced Removal of Cs(I) and Sr(II) from Aqueous Solutions.

Although Cs(I) and Sr(II) are not strategic and hazardous metal ions, their recovery from aqueous solutions is of great concern for the nuclear industry. The objective of this work consists of designing a new sorbent for the simultaneous recovery of these metals with selectivity against other metals. The strategy is based on the functionalization of algal/polyethyleneimine hydrogel beads by phosphonation. The materials are characterized by textural, thermo-degradation, FTIR, elemental, titration, and SEM-EDX analyses to confirm the chemical modification. To evaluate the validity of this modification, the sorption of Cs(I) and Sr(II) is compared with pristine support under different operating conditions: the pH effect, kinetics, and isotherms are investigated in mono-component and binary solutions, before investigating the selectivity (against competitor metals) and the possibility to reuse the sorbent. The functionalized sorbent shows a preference for Sr(II), enhanced sorption capacities, a higher stability at recycling, and greater selectivity against alkali, alkaline-earth, and heavy metal ions. Finally, the sorption properties are compared for Cs(I) and Sr(II) removal in a complex solution (seawater sample). The combination of these results confirms the superiority of phosphonated sorbent over pristine support with promising performances to be further evaluated with effluents containing radionuclides.

The pattern of neurological manifestations of tuberculosis among adult patients attending multineurological centres and hospitals in Sudan: A hospital-based cross-sectional study.

Background: Tuberculosis (TB) can involve almost any organ of the body. In the central nervous system (CNS), it can cause Pott's disease, meningitis, tuberculoma, abscess, or other manifestations. Tuberculosis is rampant in the developing world and has become a significant public health menace with the human immunodeficiency virus (HIV) dissemination. This study aimed to determine the frequency of neurological manifestations of tuberculosis among adult Sudanese patients. Methodology: A hospital-based cross-sectional study carried out in the period from September to December 2020 at multineurological centers and hospitals in Khartoum State, including Ibrahim Malik Teaching Hospital, Alshaab Teaching Hospital, Bashier, Abu Anga, Omdurman Teaching Hospitals, included adult patients diagnosed with tuberculosis-associated neurological manifestations. The data were collected by predesigned questionnaire, and then analyzed by computer using SPSS-version 25. Results: A total of 43 patients were evaluated, male patients were 24 (55.8%) and female patients were 19 (44.2%). About 31 (72.1%) of the participants had extra-pulmonary TB and 12 (27.9%) had pulmonary and extrapulmonary TB. The neurological manifestations of tuberculosis include Pott's disease in 29 (67.4%) patients (with thoracic spine most affected part), tuberculoma was second-most, occurring in 8 (18.7%) patients (with a single lesion in most of the patients), whereas tuberculous meningitis was found in 6 (13.9%). Clinical presentation was headache in 14 (32.6%) patients, convulsions in 10 (23.3%), loss of consciousness in 9 (20.9%), hemiparesis in 7 (16.3%) patients, and paraparesis in 23 (53.5%). Cranial nerve affected in 5 (11.6%) patients. All patients received antituberculosis medication and steroids, and 10 (23.2%) received anticonvulsants. Conclusions: Neurological tuberculosis should be ruled out in any young male from an endemic area who exhibits abnormalities in motor, sensory, special sense, or higher mental function. To avoid potentially fatal complications, diagnoses and treatments should be initiated as soon as possible.

Data Collection in IoT Using UAV Based on Multi-Objective Spotted Hyena Optimizer.

Today, the use of information and communication technology is very important in making the internet of things (IoT) elements distributable around the earth. With the development of IoT topics, today unmanned aerial vehicles (UAV) are utilized as a platform for gathering data from various IoT devices located worldwide. Determining the number and optimal locations of drones can minimize energy consumption in this data-collection system in the IoT. Using a promising multi-objective optimization algorithm (MOA) can achieve this goal. In this research, a bio-inspired MOA, termed the multi-objective spotted hyena optimizer (MOSHO), is employed on the data-collection platform for a group of IoT devices in a geographical area. The results of this method have been compared with other evolutionary MOAs. The analysis of the results shows that the MOSHO has a noteworthy consequence on the process of optimal energy consumption in this system, in addition to a high convergence associated with better diversity and robustness. The results of this research can be used to identify the optimization parameters in this system.

Adopting effective hierarchal IoMTs computing with K-efficient clustering to control and forecast COVID-19 cases.

The Internet of Medical Things (IoMTs) based on fog/cloud computing has been effectively proven to improve the controlling, monitoring, and care quality of Coronavirus disease 2019 (COVID-19) patients. One of the convenient approaches to assess symptomatic patients is to group patients with comparable symptoms and provide an overview of the required level of care to patients with similar conditions. Therefore, this study adopts an effective hierarchal IoMTs computing with K-Efficient clustering to control and forecast COVID-19 cases. The proposed system integrates the K-Means and K-Medoids clusterings to monitor the health status of patients, early detection of COVID-19 cases, and process data in real-time with ultra-low latency. In addition, the data analysis takes into account the primary requirements of the network to assist in understanding the nature of COVID-19. Based on the findings, the K-Efficient clustering with fog computing is a more effective approach to analyse the status of patients compared to that of K-Means and K-Medoids in terms of intra-class, inter-class, running time, the latency of network, and RAM consumption. In summary, the outcome of this study provides a novel approach for remote monitoring and handling of infected COVID-19 patients through real-time personalised treatment services.

Enhancement of Cerium Sorption onto Urea-Functionalized Magnetite Chitosan Microparticles by Sorbent Sulfonation-Application to Ore Leachate.

The recovery of strategic metals such as rare earth elements (REEs) requires the development of new sorbents with high sorption capacities and selectivity. The bi-functionality of sorbents showed a remarkable capacity for the enhancement of binding properties. This work compares the sorption properties of magnetic chitosan (MC, prepared by dispersion of hydrothermally precipitated magnetite microparticles (synthesized through Fe(II)/Fe(III) precursors) into chitosan solution and crosslinking with glutaraldehyde) with those of the urea derivative (MC-UR) and its sulfonated derivative (MC-UR/S) for cerium (as an example of REEs). The sorbents were characterized by FTIR, TGA, elemental analysis, SEM-EDX, TEM, VSM, and titration. In a second step, the effect of pH (optimum at pH 5), the uptake kinetics (fitted by the pseudo-first-order rate equation), the sorption isotherms (modeled by the Langmuir equation) are investigated. The successive modifications of magnetic chitosan increases the maximum sorption capacity from 0.28 to 0.845 and 1.25 mmol Ce g-1 (MC, MC-UR, and MC-UR/S, respectively). The bi-functionalization strongly increases the selectivity of the sorbent for Ce(III) through multi-component equimolar solutions (especially at pH 4). The functionalization notably increases the stability at recycling (for at least 5 cycles), using 0.2 M HCl for the complete desorption of cerium from the loaded sorbent. The bi-functionalized sorbent was successfully tested for the recovery of cerium from pre-treated acidic leachates, recovered from low-grade cerium-bearing Egyptian ore.

New Process for the Sulfonation of Algal/PEI Biosorbent for Enhancing Sr(II) Removal from Aqueous Solutions-Application to Seawater.

Sulfonic resins are highly efficient cation exchangers widely used for metal removal from aqueous solutions. Herein, a new sulfonation process is designed for the sulfonation of algal/PEI composite (A*PEI, by reaction with 2-propylene-1-sulfonic acid and hydroxylamine-O-sulfonic acid). The new sulfonated functionalized sorbent (SA*PEI) is successfully tested in batch systems for strontium recovery first in synthetic solutions before investigating with multi-component solutions and final validation with seawater samples. The chemical modification of A*PEI triples the sorption capacity for Sr(II) at pH 4 with a removal rate of up to 7% and 58% for A*PEI and SA*PEI, respectively (with SD: 0.67 g L-1). FTIR shows the strong contribution of sulfonate groups for the functionalized sorbent (in addition to amine and carboxylic groups from the support). The sorption is endothermic (increase in sorption with temperature). The sulfonation improves thermal stability and slightly enhances textural properties. This may explain the fast kinetics (which are controlled by the pseudo-first-order rate equation). The sulfonated sorbent shows a remarkable preference for Sr(II) over competitor mono-, di-, and tri-valent metal cations. Sorption properties are weakly influenced by the excess of NaCl; this can explain the outstanding sorption properties in the treatment of seawater samples. In addition, the sulfonated sorbent shows excellent stability at recycling (for at least 5 cycles), with a loss in capacity of around 2.2%. These preliminary results show the remarkable efficiency of the sorbent for Sr(II) removal from complex solutions (this could open perspectives for the treatment of contaminated seawater samples).