Pb2+ removal from aqueous synthetic solutions by calcium alginate and chitosan coated calcium alginate

Jin

J of Chemical Tech & Biotech

et al. 2018

BACKGROUND In this study, a low‐cost and environment‐friendly alginate–chitosan hybrid adsorbent (depicted as Alg‐Chi) was developed for the removal of Pb2+ from water. RESULTS Experimental results showed that the Alg‐Chi exhibits high selectivity and affinity for Pb2+. The selectivity coefficients of the Alg‐Chi for Pb2+/Cr3+, Pb2+/Co2+ Pb2+/Cd2+, Pb2+/Zn2+, and Pb2+/Cu2+ are all >5. It can uptake 96.8% of Pb2+ from Pb2+‐containing solutions (1.5 mmol L−1), and the maximum adsorption capacity for Pb2+ reaches 468.5 mg g−1, which is higher than that of most reported adsorbents for Pb2+. Moreover, the Alg‐Chi can also be regenerated via simple acid elution and used repeatedly without loss in adsorption ability. CONCLUSIONS Analysis of the adsorption mechanism indicated that the Alg‐Chi adsorbed Pb2+ mainly through ion exchange and chemical coordination. Green and low‐cost raw materials, simple preparation process, efficient removal efficiency and recyclable, these characteristics give the synthetic Alg‐Chi broad application prospects in the field of Pb2+‐containing wastewater treatment. © 2018 Society of Chemical Industry

Section: Resultsmentioning

confidence: 66%

Section: Maximum Adsorption Capacity For Pb 2+mentioning

confidence: 99%

Highly efficient removal of toxic Pb²⁺ from wastewater by an alginate–chitosan hybrid adsorbent

Jin

J of Chemical Tech & Biotech

et al. 2018

“…For CAS, as displayed in Figure 3a, closed cellular structures with pore sizes of 1-2 μm were observed and were well distributed on the surface, indicating a successful foaming procedure designed for the sponge preparation, which was responsible for its high toughness and elasticity. Comparatively, as seen in Figure 3b, CA showed a typical polymer-like structure, with a moderate rough surface slightly paved by cracks, while no porosity existed [30,31]. X-ray diffractograms of the prepared samples are shown in Figure 4a.…”

Section: Characterization Of the Spongementioning

confidence: 88%

An Alginate Hybrid Sponge with High Thermal Stability: Its Flame Retardant Properties and Mechanism

et al. 2019

The worldwide applications of polyurethane (PU) and polystyrene (PS) sponge materials have been causing massive non-renewable resource consumption and huge loss of property and life due to its high flammability. Finding a biodegradable and regenerative sponge material with desirable thermal and flame retardant properties remains challenging to date. In this study, bio-based, renewable calcium alginate hybrid sponge materials (CAS) with high thermal stability and flame retardancy were fabricated through a simple, eco-friendly, in situ, chemical-foaming process at room temperature, followed by a facile and economical post-cross-linking method to obtain the organic-inorganic (CaCO 3 ) hybrid materials. The microstructure of CAS showed desirable porous networks with a porosity rate of 70.3%, indicating that a great amount of raw materials can be saved to achieve remarkable cost control. The sponge materials reached a limiting oxygen index (LOI) of 39, which was greatly improved compared with common sponge. Moreover, with only 5% calcium carbonate content, the initial thermal degradation temperature of CAS was increased by 70 • C (from 150 to 220 • C), compared to that of calcium alginate, which met the requirements of high-temperature resistant and nonflammable materials. The thermal degradation mechanism of CAS was supposed based on the experimental data. The combined results suggest promising prospects for the application of CAS in a range of fields and the sponge materials provide an alternative for the commonly used PU and PS sponge materials.

“…A number of adsorbents based on biomass resources have been researched. [11][12][13][14] Among these, the SA-based adsorbent is particularly interesting. SA was derived from brown algae and bacterial biosynthesis.…”

Section: Introductionmentioning

confidence: 99%

Preparation and adsorption behaviors of sodium alginate-based adsorbent-immobilized β-cyclodextrin and graphene oxide

Shi

et al. 2017

RSC Adv.