Selective adsorption of anionic and cationic dyes on mesoporous UiO-66 synthesized using a template-free sonochemistry method: kinetic, isotherm and thermodynamic studies

Abstract

In this study, template-free mesoporous UiO-66(U) has been successfully synthesized in shortened time by sonochemical methods and provided energy savings.

Post-Synthetic Generation of Amino-Acid-Functionalized UiO-66-NH2 Metal–Organic Framework Nanostructures as an Amphoteric Catalyst for Organic Reactions

“…Moreover, the analysis of pore size distributions for UiO-66-NH 2 and UiO-66@Serine reveals the presence of mesopores with diameters of 73.36 and 66.87 Å, respectively (Figure S7). According to the IUPAC classification, these characteristics categorize the samples as mesoporous materials. , The distinct mesoporous nature (open cavities) and Zr–O clusters within the structures enable precise control over the adsorption of organic substrates in catalytic processes . Notably, the influence of serine functionalization on UiO-66 is apparent in the substantial reduction of the pore diameters.…”

ZnO@ activated carbon derived from wood sawdust as adsorbent for removal of methyl red and methyl orange from aqueous solutions

“…The pH values of the prepared materials at the point of zero charge (pH PZC ) were determined using the solid addition method, which is analogous to the drift method 21 . Briefly, the pH pzc experiments were performed in the absence of dye in 50 mL flasks wrapped with aluminum foil that contained 20 mL of 0.1 M NaCl solutions.…”

“…Therefore, pH PZC is used to show the attraction and repulsion forces between the absorbent and adsorbate during the adsorption process. Here, we determine the pH PZC by the pH drift method based on the previous literature 21 . As shown in Fig.…”

“…It indicates that the repulsion between the anionic dyes and the positively charged surface occurs in the basic conditions, which reduce the attraction and thus overall adsorption. In the other words, the electrostatic interactions between the negatively charged anionic dyes and positively charged surface adsorbents will occur in acidic conditions 21 . Hydrogen bonding between the hydrogen of the hydroxyl groups (H-donor) on the surface of adsorbent materials with oxygen or nitrogen in dye molecules (H-acceptor) can occur.…”