This study prepared fresh ferric hydroxide ( FeOxHy) by the enhanced hydrolysis of Fe ions, and investigates its adsorptive behaviors toward Sb(III) and Sb(V) through laboratory and pilot-scale studies. A contact time of 120-min was enough to achieve adsorption equilibrium for Sb(III) and Sb(V) on the FeOxHy, and the Elovich model was best to describe the adsorption kinetics of Sb(III) and Sb(V). The Freundlich model was better than Langmuir model to describe the adsorption of Sb(III) and Sb(V) on the FeOxHy, and the maximum adsorption capacity of Sb(III) and Sb(V) was determined to be 12.77 and 10.21 mmol/g the FeOxHy as Fe, respectively. Adsorption of Sb(V) decreased whereas that of Sb(III) increased with elevated pH over pH 3-10, owing to the different electrical properties of Sb(III) and Sb(V). Adsorption of Sb(III) and Sb(V) was slightly affected by ionic strength, and thus indicated the formation of inner sphere complexes between Sb and the adsorbent. Sulfate and carbonate showed little effect on the adsorption of Sb(III) and Sb(V). Phosphate significantly inhibited the adsorption of Sb(V), whereas slightly effected that of Sb(III) due to its similar chemical structure to Sb(V). Pilot-scale continuous experiment indicated the feasibility of using FeOxHy to remove Sb(V), and equilibrium adsorption capacity at the equilibrium Sb(V) concentration of 10 μg/L was determined to be 0.11, 0.07, 0.07, 0.11, and 0.12 mg/g the FeOxHy as Fe at equilibrium pH of 7.5-7.7, 6.9-7.0, 6.3-6.6, 5.9-6.4, and 5.2-5.9, respectively.
h i g h l i g h t s• Fe-Mn binary oxide achieves the simultaneous removal of Cd(II) and Sb(V).• Cd(II) at above 0.25 mmol/L improves Sb(V) adsorption onto FMBO.• Cd(II) improves more significant Sb(V) adsorption than Ca 2+ and Mn 2+ .• Sb(V) adsorption decreases whereas Cd(II) adsorption increases with elevated pH.• The increased -potential and The coexistence of cadmium ion (Cd(II)) and antimonate (Sb(V)) creates the need for their simultaneous removal. This study aims to investigate the effects of positively-charged Cd(II) on the removal of negative Sb(V) ions by Fe-Mn binary oxide (FMBO) and associated mechanisms. The maximum Sb(V) adsorption density (Q max,Sb(V) ) increased from 1.02 to 1.32 and 2.01 mmol/g in the presence of Cd(II) at 0.25 and 0.50 mmol/L. Cd 2+ exhibited a more significant positive effect than both calcium ion (Ca 2+ ) and manganese ion (Mn 2+ ). Cd 2+ showed higher affinity towards FMBO and increased its -potential more significantly compared to Ca 2+ and Mn 2+ . The simultaneous adsorption of Sb(V) and Cd(II) onto FMBO can be achieved over a wide initial pH (pH i ) range from 2 to 9, and Q Sb(V) decreases whereas Q Cd(II) increases with elevated pH i . Their combined values, as expressed by Q Sb(V)+Cd(II) , amount to about 2 mmol/g and vary slightly in the pH i range 4-9. FTIR and XPS spectra indicate the significant synergistic effect of Cd(II) on Sb(V) adsorption onto FMBO, and that little chemical valence transformation occurs. These results may be valuable for the treatment of wastewater with coexisting heavy metals such as Cd(II) and Sb(V).
a b s t r a c tThis study investigates the effects of aluminum (Al) and F interactions on the coagulation behaviors of Al salts, i.e., AlCl 3 and polymer aluminum chloride (PACl) at different basicity (B) towards fluoride. These coagulants achieve the optimum fluoride removal over pH 6-7, and PACl exhibits higher removal efficiency than AlCl 3 does over pH 4-9. The removal of fluoride is positively correlated with the content of either Al 13 or Al b in Al-based coagulants over pH 4-9 and increases in the order: PACl 2 > PACl 1 > AlCl 3 . As for PACl, the increased B from 0 to 2.4 improves fluoride removal owing to the elevated ratios of Al b . However, at further increased B to 2.8, the formation of colloidal Al species
a b s t r a c tThe species transformation of Al and fluoride in fluoride removal by Al-based coagulation and adsorption is far from being well-characterized. This study used batch-and pilot-scale experiments to compare the fluoride removal efficiency and species transformation of Al and fluoride in Al coagulation with that in Al precipitate (AlOxHy) adsorption. Al coagulation showed superior removal of fluoride compared to AlOxHy adsorption. In the coagulation process, the formation of complexed fluoride (Com-F) occurred, and Com-F concentrations increased with elevated Al dose, i.e., lowered pH. At initial pH of 8.6, free fluoride (Free-F) dominated in the adsorption system even at the high AlOxHy dose of 200 mg Al/L whereas at pH < 7.0, Com-F was the dominant species in both systems. Fluoride had an influence on Al 3+ hydrolysis and favored the transformation of Al 3+ and Al-F complexes to Al-F precipitates, and the removal of fluoride by coagulation was improved thereafter. Fluoride also promoted the dissolution of AlOxHy, the extent of which was more significant at lowered pH from 7.0 to 4.0 and at elevated ratios of fluoride to Al from 0.15 to 2.45. The formation of Al-F complexes impaired fluoride removal by adsorption. A pilot-scale field study also indicated that coagulation showed higher efficiency than adsorption in the removal of fluoride. The average ratios of Com-F to total fluoride were 0.14:1 and 0.04:1, respectively, in coagulation and adsorption processes.
Acral melanoma (AM) exhibits a high incidence in Asian patients with melanoma, and it is not well treated with immunotherapy. However, little attention has been paid to the characteristics of the immune microenvironment in AM. Therefore, in this study, we collected clinical samples from Chinese patients with AM and conducted single-cell RNA sequencing to analyze the heterogeneity of its tumour microenvironments (TMEs) and the molecular regulatory network . Our analysis revealed that genes, such as TWIST1, EREG, TNFRSF9, and CTGF could drive the deregulation of various TME components. The molecular interaction relationships between TME cells, such as MIF-CD44 and TNFSF9-TNFRSF9, might be an attractive target for developing novel immunotherapeutic agents.
This study aims to investigate the feasibility of utilizing Al-F hydroxide precipitates generated in Al hydroxide [Al(OH) 3 ] adsorption [Al(OH) 3 -F ads ] and aluminum (Al) coagulation [Al(OH) 3 -F coag ] for adsorptive removal of As(III) and As(V). Al(OH) 3 -F ads , Al(OH) 3 -F coag , and pristine Al(OH) 3 were characterized by nitrogen sorption, X-ray photoelectron spectroscopy, and fourier transform infrared spectroscopy (FTIR) before and after arsenic adsorption. The kinetic study indicated that As(III) and As(V) adsorption on these Al-based solid wastes followed the pseudo-second-order model. The calculated adsorption capacity of Al(OH) 3 -F ads and Al(OH) 3 -F coag for As(III) was 48.0 and 31.0 mg/g, while it was 84.0 and 56.3 mg/g for As(V), respectively. These adsorption capacities were 25-50% lower compared with pristine Al(OH) 3 . Anion exchange of fluoride by H 2 AsO 4 -and HAsO 4 2 -dominated in As(V) removal by Al(OH) 3 -F ads, while formation of an As-O complex played a more important role in As(V) removal by Al(OH) 3 -F coag . The maximum concentration of released fluoride after the adsorption of As(III) and As(V) by Al(OH) 3 -F ads and Al(OH) 3 -F coag was below the Chinese Class-II industrial discharge standard for fluoride (<20 mg/L). Results from this study indicated that the aluminum hydroxides generated in the fluoride removal process could be reclaimed as an adsorbent for As(III)/As(V) removal from industrial wastewater.
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