5 years ago

Synergistic immobilization of UO22+ by novel graphitic carbon nitride @ layered double hydroxide nanocomposites from wastewater

Synergistic immobilization of UO22+ by novel graphitic carbon nitride @ layered double hydroxide nanocomposites from wastewater
Cotton-like graphitic carbon nitride @ layered double hydroxides nanocomposites (g-C3N4@Ni-Mg-Al-LDH) was fabricated using lamellar g-C3N4 and rod-like Ni-Mg-Al-LDH as monomer molecules by one-step hydrothermal synthesis strategy, and it exhibited superior adsorption performance to U(VI) from wastewater based on strong synergistic effects among metal–oxygen functional groups (MgO, AlO and NiO) and free-metal functional groups (OCO, COC, CO, CC and NH2/NH/=N). The adsorption of U(VI) on g-C3N4@Ni-Mg-Al-LDH was controlled by outer-sphere surface complexation or ion exchange, which was evidenced with batch adsorption experiments and SEM, EDS, elemental mapping, FT-IR, XRD and XPS characterizations. Moreover, the maximum adsorption capacity of U(VI) on g-C3N4@Ni-Mg-Al-LDH (99.7mg·g−1) was approximately 1.5 times higher than that of U(VI) on Ni-Mg-Al-LDH (59.8mg·g−1) and approximately 3.0 times higher than that of U(VI) on g-C3N4 (31.1mg·g−1) at 298.15K, and a multilayer adsorption was existed in a low concentration of UO2 2+, while a monolayer adsorption was appeared in a high concentration of UO2 2+. The results also showed that the adsorption reaction of U(VI) was a typical endothermic and spontaneous process because of ΔHθ >0, ΔSθ >0 and ΔGθ <0. Thus, it can provide new highlights to improve the physicochemical properties of low-efficiency adsorbents based on synergistic effect through polymerization reaction, and it can be selected as superior synthetic route for the synthesis of excellent adsorbents in environmental remediation.

Publisher URL: www.sciencedirect.com/science

DOI: S1385894717312822

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.