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Abstract: In view of the low reactivity of phenol with formaldehyde under acidic condition in the synthesis of ordered mesoporous carbons, a strategy to accelerate the polymerization of phenol and formaldehyde by using designed aqueous basic/acidic conditions (first weakly basic condition then highly acidic condition) is developed. The first weakly basic condition benefits the formation of hydroxymethyl phenols at 313K. The latter highly acidic condition mainly induces the condensation reaction between the formed hydroxymethyl phenols, as well as the self-assembly of phenol–formaldehyde and block copolymer template. After removal of the template, the obtained carbon exhibits highly ordered hexagonal mesostructure with a surface area of 760m2 g−1, large pore volume (0.64cm3 g−1) and uniform pore size (3.32nm). This developed strategy affords a simple and highly reproducible approach for the synthesis of ordered mesoporous carbon from the less expensive phenol under strong acidic condition, which also provides a wide and easily accessed synthesis condition for the further functionalization, such as the in situ introducing of metal ions. [Copyright &y& Elsevier]

Nanocomposites composed of nanoparticles of iron oxide and aluminium oxide (Fe2O3–Al2O3) with a unique structure show a remarkable catalytic performance in Fischer–Tropsch synthesis (FTS), compared with the traditional iron-based catalyst. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) have been widely employed for metal ion adsorption owing to their inherent advantages, encompassing low crystal density, well-organized organic unit structures, adjustable pore size, and remarkable structural stability. However, it is still a great challenge to design excellent COFs with high adsorption and advanced purification capabilities for Pb2+ and Cd2+ ions. Herein, hydrazine-linked COFs (COF-TCH) were prepared for effective adsorption and advanced purification of metal ions. The adsorption capacity of COF-TCH for Pb2+ and Cd2+ ions are 395.3 and 153.5 mg/g, respectively. Moreover, the Pb2+ and Cd2+ ions in water can be treated from 75 and 30 mg L−1 to less than 0.01 and 0.003 mg L−1, respectively, indicating the excellent adsorption and advanced purification capability of COF-TCH. This is a rare example of COFs adsorbent that deeply purify water to meet the guideline values in drinking water for the World Health Organization. FT-IR, XPS and quantum mechanics calculation were performed to understand the adsorption mechanism. The remarkable adsorption and advanced purification capability of COF-TCH for Pb2+ and Cd2+ ions can be attributed to the synergistic interaction between the amine and thione groups, which can easily complex with Pb2+ and Cd2+ ions to form stable five-membered ring structure in COF-TCH. In addition, COF-TCH still remains an adsorption capacity of over 90% after ten adsorption-desorption cycles, indicating its excellent reusability and stability. COF-TCH with high adsorption and advanced purification capability, high stability, low cost and reusability has enormous practical application potential in high-performance remediation of Pb2+ and Cd2+ contaminated water. [Display omitted] [ABSTRACT FROM AUTHOR]

• Facile room-temperature synthesis of urchin-like magnetic COFs. • Thiol and thioether functionalized magnetic COFs with excellent adsorption capacity for mercury species (> 550 mg g−1). • Rapid MSPE process for inorganic mercury, monomethylmercury and ethylmercury. • Figures of merit: LOD (0.17-0.96 ng L−1), Linearity range (0.55-1000 ng L−1), RSD (<5.4 %). • The proposed method can be applied in the samples with complex matrix, such as seawater and biological samples. A simple and practical magnetic solid-phase extraction high-performance liquid chromatography-inductively coupled plasma mass spectrometry (MSPE-HPLC-ICP-MS) method for extraction and determination of trace mercury species, including inorganic mercury (IHg), monomethylmercury (MeHg) and ethylmercury (EtHg), was developed. The MSPE adsorbent, urchin-like thiol and thioether-functionalized magnetic covalent organic frameworks (Fe 3 O 4 @COF-S-SH), was synthesized by coating covalent organic frameworks (COFs) on the surface of Fe 3 O 4 nanoparticles at room temperature and then easily grafting 1,2-Ethanedithiol on the COFs. The as-prepared Fe 3 O 4 @COF-S-SH has strong adsorption capacity for IHg, MeHg and EtHg, with excellent static adsorption capacity: 571, 559 and 564 mg g−1, respectively. The parameters influencing the extraction and enrichment had been optimized, including pH, adsorption and desorption time, composition and amount of the eluent, co-existing ions and dissolved organic materials etc. Under the optimized condition, the limit of detection (3δ) of the proposed method were 0.96, 0.17 and 0.47 ng L−1 for IHg, MeHg and EtHg, and the developed method has high actual enrichment factors of 370, 395, 365-fold for IHg, MeHg and EtHg based on 200 mL samples, respectively. The high accuracy and reproducibility has been proved by the spiked recoveries (96.0‒108 %) in real water samples and determination of the certified reference material. Both the adsorption and desorption process can be completed within 5 min. The proposed method with simple operation, short pre-concentration time and high sensitivity has been successfully applied to mercury speciation at trace levels in the samples with complicated matrices, including underground water, surface water, sea water and fish samples. [ABSTRACT FROM AUTHOR]