Abstract

Reducing input of phosphorus is the key step for control of eutrophication and algal blooming in freshwater lakes. Adsorption technology is a cost-effective technology for phosphate removal in water for the purpose. Thus, in this study, a novel Fe–Mn–La tri-metal composite sorbent was developed, and then evaluated for phosphate removal. The results showed that the maximum adsorption capacity could be approached to 61.80 mg g−1 at 25°C under pH of 6.03. Adsorption of phosphate by Fe–Mn–La tri-metal composite adsorbent fitted better by pseudo-second-order kinetic equation and Langmuir model, which suggested that the adsorption process was surface chemical reactions and mainly in a monolayer coverage manner. The thermodynamic study indicated that the adsorption reaction was an endothermic process. The phosphate removal gradually decreased with the increasing of pH from 3.02 to 11.00. The sequence of coexisting anions competing with phosphates was that CO32− > Cl− > SO42− > NO3−. Dissolved organic matter, fulvic acid as a representative, would also decrease adsorption capacities of phosphate by Fe–Mn–La tri-metal composite adsorbents. Adsorption capacity would be decreased with increasing addition of adsorbents, while removal efficiency would be increased in this process. The Fe–Mn–La tri-metal composite adsorbent showed a good reusability when applied to removal of dissolved phosphate from aqueous solutions. The Fourier transform infrared spectrometer and X-ray photoelectron spectroscopy analyses indicated that some hydroxyl groups (–OH) on the surface of adsorbent were replaced by the adsorbed PO43−, HPO42−, or H2PO4−. Aggregative results showed that the novel Fe–Mn–La tri-mental composite sorbent is a very promising adsorbent for the removal of phosphate from aqueous solutions.

Highlights

  • Phosphorus (P) is an important nutrient that restricts life such as microbial production in many freshwater and marine environments (Hudson et al, 2000)

  • Based on the correlation coefficients (R2), the pseudo-second-order kinetic equation was the best model for description of adsorption of phosphate by the Fe–Mn–La tri-metal material (FML) absorbent.These results suggest that surface chemical reaction between adsorbent active sites and phosphates is likely a dominant process for adsorption of phosphates by FML adsorbent (Lp et al, 2013)

  • A novel Fe–Mn–La tri-mental composite sorbent was developed for phosphate removal by co-precipitation

Read more

Summary

Introduction

Phosphorus (P) is an important nutrient that restricts life such as microbial production in many freshwater and marine environments (Hudson et al, 2000). Excessive discharge of phosphorus into water bodies such rivers, lakes, and inland seas has resulted in eutrophication and degradation of water quality (Correll, 1998; Smith et al, 2014; Smith and Schindler, 2009).Cultural eutrophication even has become the primary water quality issue for most of the freshwater and coastal marine in recent decades (Smith and Schindler, 2009). Emission standards of total phosphorus (TP) is generally controlled to 1.0 mg lÀ1 (Class I A emission standard) for waste water in China. It is important to reduce P from water bodies directly to control algal blooming

Methods
Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.