Eco-friendly engineering of micro composite-based hydroxyapatite bio crystal and polyaniline for high removal of OG dye from wastewater: Adsorption mechanism and RSM@BBD optimization.

The presence of harmful substances such as dyes in water systems poses a direct threat to the quality of people's lives and other organisms living in the ecosystem. Orange G (OG) is considered a hazardous dye. The existing paper attempts to evaluate a low-cost adsorbent for the effective removal of OG dye. The developed adsorbent Polyaniline@Hydroxyapatite extracted from Cilus Gilberti fish Scale (PANI@FHAP) was elaborated through the application of the in situ chemical polymerization method to incorporate PANI on the surface of naturally extracted hydroxyapatite FHAP. The good synthesis of PANI@FHAP was evaluated through multiple techniques including X-ray diffraction (XRD), Scanning electron microscopy coupled with energy dispersive X-ray spectrometry (SEM/EDS), Fourier Transforms Infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA) coupled with thermal differential analysis (DTA) analysis. The results reveal a highly ordered disposition of PANI chains on FHAP, resulting in a well-coated FHAP in the PANI matrix. Furthermore, the presence of functional groups on the surface of PANI such as amine (-NH2) and imine (=NH) groups would facilitate the removal of OG dye from contaminated water. The adsorption of OG onto PANI@FHAP was conducted in batch mode and optimized through response surface methodology coupled with box-Behnken design (RSM/BBD) to investigate the effect of time, adsorbent dose, and initial concentration. The outcomes proved that OG adsorption follows a quadratic model (R2 = 0.989). The kinetic study revealed that the adsorption of OG fits the pseudo-second-order model. On the other hand, the isotherm study declared that the Freundlich model is best suited to the description of OG adsorption. For thermodynamic study, the adsorption of OG is spontaneous in nature and exothermic. Furthermore, the regeneration-reusability study indicates that PANI@FHAP could be regenerated and reused up to five successive cycles. Based on the FTIR spectrum of PANI@FHAP after OG adsorption, the mechanism governing OG adsorption is predominantly driven by π-π interaction, electrostatic interaction, and hydrogen bonding interactions. The obtained results suppose that PANI@FHAP adsorbent can be a competitive material in large-scale applications.

Flexible Synthesis of Bio-Hydroxyapatite/Chitosan Hydrogel Beads for Highly Efficient Orange G Dye Removal: Batch and Recirculating Fixed-Bed Column Study.

The use of fish waste as a source material for the development of functional beads has significant potential applications in the fields of materials science and environmental sustainability. In this study, a biomaterial bead of chitosan was cross-linked with bio-hydroxyapatite (Bio-Hap/Cs) through the encapsulation process to create a stable and durable material. The beads are characterized using scanning electron microscopy combined with energy dispersive X-ray spectrometry, Fourier transform infrared spectroscopy, and X-ray diffraction techniques. The adsorption efficiency of Bio-Hap/Cs hydrogel beads was evaluated by using Orange G (OG) dye in both batch and recirculating column systems, and the effect of various parameters on the adsorption capacity was investigated. In the batch study, it was found that OG removal increased with an increasing pH and adsorbent dose. However, in the recirculating column system, a higher bed height and lower flow rate led to increased removal of the OG dye. The kinetic study indicated that the pseudo-second-order model provided a good description of OG adsorption onto Bio-Hap/Cs beads in both batch and recirculating processes, with a high coefficient correlation. The maximum adsorbed amounts are found to be 19.944 mg g-1 and 9.472 mg g-1 in batch and recirculating processes, respectively. Therefore, Bio-Hap/Cs hydrogel beads have demonstrated an effective and reusable material for OG dye remediation from aqueous solutions using recirculating adsorption processes.

Fermentative optimization and characterization of exopolysaccharides from Enterococcus faecium F58 isolated from traditional fresh goat cheese.

This study focused on optimizing the fermentation-based production of Exopolysaccharides (EPS) from Enterococcus faecium F58 initially isolated from traditional Moroccan Jben, a fresh goat cheese. Using the central composite design, yeast extract, MnSO4, and time affect EPS concentration. The highest experimental and predicted EPS production yields were 2.46 g/L ± 0.38 and 2.86 g/L, respectively. Optimal concentrations of yeast extract (4.46 g/L) and MnSO4 (0.011 g/L) were identified after 26 h at 30 °C. Characterization of EPS was conducted using SEM with EDX, XRD, and FTIR analyses. These tests revealed a specific morphology and an amorphous structure. Additionally, thermogravimetric analysis indicated adequate EPS stability up to 200 °C with anti-adhesion properties against different pathogens. This study offers valuable insights into the optimized production of EPS from Enterococcus faecium F58, which exhibits significant structural and functional properties for various applications in the food and biotechnology industries. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01424-9.

The reliability of evaporation ponds as a final basin for industrial effluent: Demonstration of an environmental risk management methodology.

Recognizing and assessing environmental risk are key components of every industry management strategy. Projects need to make sure that a detailed environmental risk management strategy is applied by methodically recognizing and addressing threats from internal and external influences to comply with regulatory standards for environmental preservation and safeguarding. This study's goal is to use a novel technique to assess the impact of environmental risks related to the use of evaporation ponds as final basins for industrial effluents. It employs qualitative and statistical methodologies to identify areas where engineering and managerial safeguards' structure, functioning, and lines of defense have flaws that might result in an ecologically hazardous occurrence. Additionally, it will offer a risk evaluation based on the gravity of the impact and the likelihood that the environmental occurrence would happen by using evaporation ponds to store industrial effluents. While the environmental threat would be entirely removed, it must be capable of reducing it to ALARP. The environmental risk assessment matrix will serve as a key factor in determining whether the environmental risk level linked with an evaporation pond is acceptable, as determined by the likelihood and impacts. The result of this research allows industrial units to recognize and control potential environmental risks associated with effluents by practically implementing a new environmental risk matrix based on several environmental and ecological effects with probability factors.•This study aims to assist industrial operators, especially power plants, manage environmental risk by combining ALARP concepts with other factors to evaluate risk acceptance and tolerance levels.•The Physico-chemical characteristics of effluent collected in the evaporation pond reveal that evaporation has a deleterious impact on such industrial effluent, as evidenced by a large increase in various effluent properties, some of which exceed the limit values.•A risk evaluation found that effluent collected in the evaporation pond has a detrimental negative impact on industrial effluents. This was evidenced by a significant rise in associated activities. This could increase the expense of operating and managing evaporation ponds, which could harm the ecosystem.

Low-cost materials as vehicles for pesticides in aquatic media: a review of the current status of different biosorbents employed, optimization by RSM approach.

Water contamination by pesticides is increasing dramatically due to population growth and the extensive use of pesticides in agriculture, leading to grave environmental and health concerns. Thus, efficient processes and the design and development of effective treatment technologies are required due to the enormous demand for fresh water. The adsorption approach has been widely used to remove organic contaminants such as pesticides because of its performance, less expense, high selectivity, and simplicity of operation compared to other treatment technologies. Among alternative adsorbents, biomaterials abundantly available for pesticide sorption from water resources have attracted the attention of researchers worldwide. The main objective of this review article is to (i) present studies on a wide range of raw or chemically modified biomaterials potentially effective in removing pesticides from aqueous media; (ii) indicating the effectiveness of biosorbents as green and low-cost materials for removing pesticides from wastewater; and (iii) furthermore, report the application of response surface methodology (RSM) for modeling and optimizing adsorption.

A novel hydrogel beads based copper-doped Cerastoderma edule shells@Alginate biocomposite for highly fungicide sorption from aqueous medium.

The engineering of a novel biocomposite based on Cerastoderma edule shells doped with copper and alginate (Ce-Cu@Alg) forming hydrogel beads was used for batch and dynamic adsorption thiabendazole (TBZ) pesticide from water. The prepared biosorbent was analyzed by various characterization techniques such as scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), Brunauer-Emmett-Teller analysis (BET), and energy dispersive spectroscopy (EDS), thermogravimetric and differential analysis (TGA-DTA). The results of the TBZ batch biosorption by Ce-Cu@Alg composite showed that the Langmuir model was the most adequate to describe the adsorption process, with a maximum adsorption capacity value of 21.98 mg/g. Moreover, the adsorption kinetics were adjusted by the pseudo-second-order model. The optimal conditions determined by the RSM approach coupled with the CCD design were 100 ppm of initial TBZ concentration, a Ce-Cu@Alg beads dose of 6 g/L and a contact time of 180 min for maximum removal of 83.42%. On the other hand, the TBZ sorption on a fixed bed of Ce-Cu@Alg beads was effective at high column height, low effluent flow and low solution concentration. The Thomas model was best fitted to the kinetic data. This study shows the possibility of using this new hybrid biocomposite in the industrial sector to treat large effluent volumes.

An Overall Validation Approach Based on ß-Content, γ-Confidence Tolerance Interval, and Uncertainty Profile: Application to LC-MS/MS Quantification of Carbendazim in Drinking Water.

BACKGROUND: Carbendazim is a fungicide which can seep into the water supply, presenting a public health risk, and therefore the accurate trace determination of this substance is very important. OBJECTIVE: The purpose of the study is to take a top-down analytical validation approach in order to determine the amount of carbendazim in drinking water by using an SPE-LC-MS/MS technique. METHODS: Quantification of carbendazim using solid-phase extraction coupled with LC-MS/MS was used in order to ensure the accuracy of the analytical method and to control the risk of its routine application. An overall validation methodology based on two-sided tolerance interval type ß-content, γ-confidence has been applied for the validation and estimation of uncertainty by building a decision graphical tool called the "uncertainty profile" by using the statistical process known as the Satterthwaite approximation with no recourse to additional data by satisfying intermediate precision condition for each concentration level within the acceptance limits fixed in advance. RESULTS: The process of validation is based on the selection of a linear weighted 1/X model enabling validation of the carbendazim dosage using LC-MS/MS in the range of working concentrations as the ßγ-CCTI fell inside acceptable limits of ±10%, and the relative expanded uncertainty did not surpass 7% regardless of the ß values (66.7, 80, and 90%) and the 1- γ = risk (10 and 5%). CONCLUSION: The application of the uncertainty profile approach for full validation of a SPE-LC-MS/MS assay for the quantification of carbendazim has been successfully achieved. HIGHLIGHTS: Implementation of a full validation strategy based on validation and measurement uncertainty with no additional effort using data from analytical validation under intermediate precision conditions at each level of concentration for carbendazim quantification in drinking water using SPE-LC-MS/MS. So we have shown the flexibility of this approach for carbendazim assay by LC-MS/MS. Indeed, It provides an efficient decision-making tool that allows selection and modification of ß-content and γ-confidence values.

High thiabendazole fungicide uptake using Cellana tramoserica shells modified by copper: characterization, adsorption mechanism, and optimization using CCD-RSM approach.

In this paper, Cellana tramoserica (CT) shells were modified by copper and used as an adsorbent to remove thiabendazole (TBZ) from aqueous media. The removal efficiency of TBZ onto CT shells and modified Cellana tramoserica (CT-Cu) shells was investigated by considering the following parameters: initial pesticide concentration, solution pH, agitation time, temperature, and adsorbent mass. The experimental results show that the pseudo-first-order and Langmuir models well describe the adsorption process. The maximum adsorption amount for CT and CT-Cu is 319.68 mg/g and 376.12 mg/g, respectively. CT-Cu showed higher TBZ removal efficiency than CT, explained by the ligand exchange between the water and the pesticide molecules in the metal coordination sphere. Response surface methodology combined with central composite design (RSM-CCD) was used to optimize the adsorption conditions. Optimized values were obtained at 5 for pH, 50 ppm, 120 min, and 20 mg of CT-Cu adsorbent. Under these optimal conditions, 91% of TBZ was removed by adsorption onto CT-Cu. Graphical abstract.

Composites with alginate beads: A novel design of nano-adsorbents impregnation for large-scale continuous flow wastewater treatment pilots.

The sorption capacity of cadmium (Cd (II)) on three new generated nanocomposite beads sodium alginate (SA) based; SA-Clay (SA-C) beads, SA-Phosphate (SA-P) beads, and SA- Activated Charcoal (SA-Ch) beads was investigated in a batch scale, then a continuous flow reactor. The highest adsorption capacity (137 mg/g) was obtained for SA-Ch using 1000 mg/L of initial Cd (II). The isotherm results showed that the adsorption equilibrium is compatible with the Langmuir isotherm and the sorption capacity of SA-Nano-adsorbent beads is very high. The models used for representing kinetic data was given that the removal of Cd (II) be well-fitted by second-order reaction kinetics. For the fixed bed column treatment, the maximum breakthrough times were 30, 38, and 48  h respectively for the SA-C, SA-P, and SA-Ch. According to the obtained results, it was concluded that SA-Nano-adsorbent bead is an excellent designed material as a nanocomposite for cadmium elimination from wastewater in a continuous treatment process.

Strategy to identify the causes and to solve a sludge granulation problem in methanogenic reactors: application to a full-scale plant treating cheese wastewater.

Granulation of biomass is at the basis of the operation of the most successful anaerobic systems (UASB, EGSB and IC reactors) applied worldwide for wastewater treatment. Despite of decades of studies of the biomass granulation process, it is still not fully understood and controlled. "Degranulation/lack of granulation" is a problem that occurs sometimes in anaerobic systems resulting often in heavy loss of biomass and poor treatment efficiencies or even complete reactor failure. Such a problem occurred in Mexico in two full-scale UASB reactors treating cheese wastewater. A close follow-up of the plant was performed to try to identify the factors responsible for the phenomenon. Basically, the list of possible causes to a granulation problem that were investigated can be classified amongst nutritional, i.e. related to wastewater composition (e.g. deficiency or excess of macronutrients or micronutrients, too high COD proportion due to proteins or volatile fatty acids, high ammonium, sulphate or fat concentrations), operational (excessive loading rate, sub- or over-optimal water upflow velocity) and structural (poor hydraulic design of the plant). Despite of an intensive search, the causes of the granulation problems could not be identified. The present case remains however an example of the strategy that must be followed to identify these causes and could be used as a guide for plant operators or consultants who are confronted with a similar situation independently of the type of wastewater. According to a large literature based on successful experiments at lab scale, an attempt to artificially granulate the industrial reactor biomass through the dosage of a cationic polymer was also tested but equally failed. Instead of promoting granulation, the dosage caused a heavy sludge flotation. This shows that the scaling of such a procedure from lab to real scale cannot be advised right away unless its operability at such a scale can be demonstrated.

New eco-friendly animal bone meal catalysts for preparation of chalcones and aza-Michael adducts.

UNLABELLED: Two efficient reactions were successfully carried out using Animal Bone Meal (ABM) and potassium fluoride or sodium nitrate doped ABMs as new heterogeneous catalysts under very mild conditions. After preparation and characterization of the catalysts, we first report their use in a simple and convenient synthesis of various chalcones by Claisen-Schmidt condensation and then in an aza-Michael addition involving several synthesized chalcones with aromatic amines. All the reactions were carried out at room temperature in methanol; the chalcone synthesis was also achieved in water environment under microwave irradiation. Doping ABM enhances the rate and yield at each reaction. Catalytic activities are discussed and the ability to re-use the ABM is demonstrated. RESULTS: For Claisen-Schmidt the use of ABM alone, yields never exceeded 17%. In each entry, KF/ABM and NaNO3/ABM (79-97%) gave higher yields than using ABM alone under thermic condition. Also the reaction proceeded under microwave irradiation in good yields (72-94% for KF/ABM and 81-97% for NaNO3/ABM) and high purity. For aza-Michael addition the use of ABM doped with KF or NaNO3 increased the catalytic activity remarkably. The very high yields could be noted (84-95% for KF/ABM and 81-94% for NaNO3/ABM). CONCLUSION: The present method is an efficient and selective procedure for the synthesis of chalcones an aza-Michael adducts. The ABM and doped ABMs are a new, inexpensive and attractive solid supports which can contribute to the development of catalytic processes and reduced environmental problems.

Dehalogenation of chlorinated ethenes and immobilization of nickel in anaerobic sediment columns under sulfidogenic conditions.

A sediment column study was carried out to demonstrate the bioremediation of chloroethene- and nickel-contaminated sediment in a single anaerobic step under sulfate-reducing conditions. Four columns (one untreated control column and three experimental columns) with sediment from a chloroethene- and nickel-contaminated site were investigated for 1 year applying different treatments. By stimulating the activity of sulfate-reducing bacteria by the addition of sulfate as supplementary electron acceptor, complex anaerobic communities were maintained with lactate as electron donor (with or without methanol), which achieved complete dehalogenation of tetra- and trichloroethenes (PCE and TCE) to ethene and ethane. A few weeks after sulfate addition, production of sulfide increased, indicating an increasing activity of sulfate-reducing bacteria. The nickel concentration in the effluent of one nickel-spiked column was greatly reduced, likely due to the enhanced sulfide production, causing precipitation of nickel sulfide. At the end of the study, 94% of the initial amount of nickel added to that column was recovered in the sediment As compared to the untreated (nonspiked) control column, all chloroethene-spiked columns ladditions of PCE and TCE) showed a permanent release of small chloride ion quantities (approximately 0.5-0.7 mM chloride), which were detected in the effluents a few weeks after sulfide production was observed for the first time. The formation of ethene and ethane as final products after dechlorination of PCE and TCE was detected in some effluents and in some gas phases of the columns. Other metabolites or intermediates (such as DCE isomers) were only detected sporadically in negligible quantities. The results of this study demonstrated thatmicrobial activity stimulated under sulfate-reducing conditions can have a beneficial effect on both the precipitation of heavy metals and the complete dechlorination of organochlorines. The strongly negative redox potential created by the activity of sulfate-reducing bacteria may be one factor responsible for stimulating the activity of the dehalogenating bacteria in the test columns.

Combining photolysis and bioprocesses for mineralization of high molecular weight polyacrylamides.

The influence of ultraviolet photolysis as a pretreatment to the aerobic and anaerobic biological mineralization of a 14C-polyacrylamide was assessed using a series of radiorespirometry bioassays. The polyacrylamide studied was non-ionic with molecular weights ranging between 100,000 and 1 million. Aerobic and anaerobic biomineralization of the unphotolysed (raw) polyacrylamide was found to be only 0.60% and 0.70%, respectively, after 6 weeks of incubation, and hence indicative of the natural recalcitrance of polyacrylamide to microbial degradation. The effectiveness of UV irradiation in the physical breakdown of the polyacrylamide chain into oligomers was demonstrated by the shift in the molecular weight distribution and the positive correlation between the time of irradiation and the degree of its biological mineralization. The molecular weight fraction below 3 kD, which represents only 2% of the raw polyacrylamide, was increased to 41, 60 and 80% after 12, 24 and 48 hours of photolysis, respectively. This in turn, yielded, after 6 weeks of incubation, an aerobic mineralization of 5, 17 and 29% of 150 mg/L polyacrylamide, respectively, and an anaerobic mineralization of 3, 5 and 17%, respectively. Biomass acclimation substantially improved the specific initial rate of biomineralization of the photolysed polyacrylamides, but not the overall percentage of polyacrylamides mineralized.