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In response to environmental concerns at the global level, there is considerable momentum in the exploration of materials derived from waste that are both sustainable and eco-friendly. In this study, CS-Fe (carbon, silica, and iron) composite was synthesized from coal gasification slag (CGS) and innovatively applied as a catalyst to activate PS (persulfate) for the degradation of trichloroethylene (TCE) in water. Scanning electron microscope (SEM), fourier transmission infrared spectroscopy (FTIR), energy dispersive x-ray spectroscopy (EDS), brunauer, emmet, and teller (BET) technique, and x-ray diffractometer (XRD) spectra were employed to investigate the surface morphology and physicochemical composition of the CS-Fe composite. CS-Fe catalyst showed a dual nature by adsorption and degradation of TCE simultaneously, displaying 86.1% TCE removal in 3 h. The synthesized CS-Fe had better adsorption (62.1%) than base material CGS (36.4%) due to a larger BET surface area (770.8 m2 g−1), while 24.0% TCE degradation was recorded upon the activation of PS by CS-Fe. FTIR spectra confirmed the adsorption and degradation of TCE by investigating the used and fresh samples of CS-Fe catalyst. Scavengers and Electron paramagnetic resonance (EPR) analysis confirmed the availability of surface radicals and free radicals facilitated the degradation process. The acidic nature of the solution favored the degradation while the presence of bicarbonate ion (HCO 3 −) hindered this process. In conclusion, these results for real groundwater, surfactant-added solution, and degradation of other TCE-like pollutants propose that the CS-Fe composite offers an economically viable and favorable catalyst in the remediation of organic contaminants within aqueous solutions. Further investigation into the catalytic potential of coal gasification slag-based carbon materials and their application in Fenton reactions is warranted to effectively address a range of environmental challenges. [Display omitted] • CGS is used to synthesize CS-Fe composite to activate persulfate for TCE degradation. • CS-Fe composite exhibited significant absorbance capacity. • ROS played a dominant role in the degradation of TCE in the PS/CS-Fe system. • PS/CS-Fe system favors acidic solution for efficient degradation of TCE. • The existence of HCO 3 ˉ hindered TCE degradation. [ABSTRACT FROM AUTHOR]

In the age of the information-based economy and the rapid advancements of data schemes, business management has been faced with extraordinary difficulties and has entered into a reasonable period where the board's conventional enterprise execution assessment centers around the interests of investors. Speculators accept money-related information as their basis and focus on the investigation of material fascination, and in the event of the off chance that they do not, they cannot confirm the next economy period. In this way, enterprise execution reflects the interests of investors and business strategists for the needs of partners, which is significant for the forthcoming rivalry. Given that, the collection of data is a significant research tool that has lately been considered by researchers for data examination. In this paper, we have established multi-criteria decision-making methods for the assessment of business execution with spherical fuzzy information. We have applied Hamacher aggregation operators such as the spherical cubic fuzzy Hamacher weighted averaging (SCFHWA) operator, the spherical cubic fuzzy Hamacher ordered weighted averaging (SCFHOWA) operator, the spherical cubic fuzzy Hamacher hybrid averaging (SCFHHA) operator, the spherical cubic fuzzy Hamacher weighted geometric (SCFHWG) operator, the spherical cubic fuzzy Hamacher ordered weighted geometric (SCFHOWG) operator, and the spherical cubic fuzzy Hamacher hybrid geometric (SCFHHG) operator for the appraisal of the best choice of enterprise. We ultimately defend the proposed approach with the existing strategies for possibility and adequacy. [ABSTRACT FROM AUTHOR]

Remediation and management of industrial wastewater (IWW) using hydrophytes act as one of the cost effective and environmentally friendly technologies. The present study was conducted to assess the role and efficiency of selected four hydrophyte species through constructed wetland (CW) for the removal of heavy metals (HMs) from IWW. Samples of wastewater (WW) were collected from the main drain of Hayatabad Industrial Estate (Peshawar, Pakistan) and analysed for HMs like cadmium (Cd), copper (Cu) and lead (Pb) along with basic physicochemical parameters like pH, electric conductivity (EC), total suspended solids (TSS), total dissolved solids (TDS), dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), dissolved organic carbon (DOC) through standard analytical methods. Four hydrophytes species such as Typha latifolia (cattail), Eichhornia crassipes (water hyacinth), Lemna gibba (duck weed) and Pistia stratiotes (water cabbage) were transplanted into CW (mix cultivation). Each selected species was also cultivated in individual pots for investigating their efficiency to remove HMs. The Cd, Cu and Pb removal efficiency of CW was recorded as 39.5%, 80.3% and 85.5%, respectively. The removal efficacy of hydrophyte species including cattail, water hyacinth, duck weed and water cabbage was 96.2%, 72.2%, 60.4% and 93.3%, respectively for Cd, while 83.6%, 82.3%, 90.0% and 81.7% for Cu and 95.9%, 78.0%, 91.3% and 97.1% for Pb, respectively. Findings of T-Test and One-Way ANOVA showed that the concentrations of Cd, Cu and Pb in IWW were significantly (P ≤ 0.01) reduced by the treatment of hydrophytes revealing the higher efficiency of CW and selected species used in this study. The HMs were removed in order of Pb > Cu > Cd. Most efficient removal for Cd was found by water cabbage, Cu by duck weed and Pb by water hyacinth. It was concluded that CW is one of the environmentally friendly and cost-effective technologies that can be used for the treatment of IWW due to the efficiency of hydrophytes species in terms of HMs removal. Image 1 • Removal efficacy of four hydrophytes were assessed for wastewater toxic metals. • Cd, Cu and Pb were significantly reduced (P ≤ 0.01) by Constructed Wetland. • Hydrophytes significantly (P ≤ 0.01) reduced Cd, Cu, Pb concentrations in wastewater. • Constructed wetland efficiently removed 39.5% Cd, 80.3% Cu and 85.5% Pb. • Cd was efficiently removed by P. stratiotes, Cu by L. gibba and Pb by E. crassipes. [ABSTRACT FROM AUTHOR]

Directive, acid and reactive dyes are the carcinogenic dyes which have complex structures and difficult to remove from the industrial wastewater. In this study, coal fly ash (CFA) was modified with HCl and NaOH solution and used for the removal of direct fast scarlet 4BS, direct sky blue 5B, acid navy blue R, and reactive turquoise blue KN-G dyes. Laboratory experiments were carried out to analyze the performance of modified coal fly ash (MCFA) to check the removal efficiency and adsorption capacity of dyes. The maximum removal efficiency of direct fast scarlet 4BS and direct sky blue 5B were recorded 96.03% and 93.820%, respectively using 0.05 g adsorbent dosage at 100 mg/L initial concentration. The results of MCFA were compared with carbon black, chitosan, starch, zeolite and unmodified coal fly ash (UMCFA) at lower dosage 0.05 g and higher dosage 0.4 g. Adsorption isotherm were analyzed by Langmuir and Freundlich model by different dyes concentrations, the result stated that Freundlich and Langmuir model (±0.9918, ±0.9974) was fitted by chemisorption and physisorption methods for all four dyes. Adsorption kinetic were also determined by Pseudo-first-order and Pseudo-second-order at different contact times with dye molecules and adsorbent active sites, and the results showed that the adsorption behaviors of all four dyes were described better by pseudo-second-order kinetics than pseudo-first-order kinetics. Recommended dosage of modified fly ash is between 10 ‱ to 20 ‱ for simulated textile industrial waste water and regeneration temperature is 300 ℃. [Display omitted] • Coal fly ash was modified by HCl and NaOH for the dye adsorption. • After modification the surface area and porosity of CFA were increased. • Modified coal fly ash was used for the removal of directive, acid and reactive dyes. • Maximum removal efficiency of directive dye was recorded up to 98% by using modified CFA. • The results of MCFA were compared with carbon black, chitosan, starch, zeolite and unmodified coal fly ash. [ABSTRACT FROM AUTHOR]

Environmentally friendly and cost-effective techniques are required to reclaim land degraded during mining activities. Bioaccumulation of heavy metals (HMs) in vegetables grown on contaminated soils can increase human health risks. The potential effects of hardwood biochar (HWB) was assessed for chromium (Cr), zinc (Zn), copper (Cu), manganese (Mn) and lead (Pb) bioavailability in mine-contaminated soils and their subsequently bioaccumulation in crops and associated health risk. HWB was applied to chromium-manganese mine contaminated soils at the rate of 3% to investigate the efficiency of HWB for the second crop in crop rotation technique. Cilantro (Coriandrum sativum) and spinach (Spinaccia oleracea) were grown as second crop in the same pots which were already used for rice cultivation as first crop (without adding further amendments). Application of HWB decreased the concentrations of Cr, Zn, Cu, Mn, and Pb in cilantro by 25.5%, 37.1%, 42.5%, 34.3%, and 36.2%, respectively as compared to control. In spinach, the reduction in concentrations of Cr was 75.0%, Zn 24.1%, Cu 70.1%, Mn 78.0%, and Pb 50.5% as compared to control. HWB significantly (P < 0.01) reduced the HMs uptake in spinach cultivated in the amended soils as compared to the spinach in control. Bioaccumulation factor results also indicate that HWB decreased the bioaccumulation of selected HMs in cilantro and spinach, thus reducing health risks. Results of the study clearly demonstrate that the use of HWB can significantly reduce HMs in vegetables, associated health risk and improve food quality, therefore can be used as soil amendment for reclamation of mine-degraded soils. • Mine (chromium-manganese) contaminated soils were used in these experiments. • Hardwood Biochar (HWB) was added to the contaminated soils at 3% application rate. • HWB significantly (P ≤ 0.05) reduced heavy metals uptake by cilantro and spinach. • HWB reduced ADI and HQ values for Cr, Cu, Pb, Zn and Mn. • ILTCR for Pb significantly (P ≤ 0.01) decreased (cilantro 36% and spinach 50%) by HWB. [ABSTRACT FROM AUTHOR]