Removing phosphorus from aqueous solutions by using iron-modified corn straw biochar

Abstract

Iron-modified corn straw biochar was used as an adsorbent to remove phosphorus from agricultural runoff. When agricultural runoffs with a total phosphorus (TP) concentration of 1.86 mg·L⁻¹ to 2.47 mg·L⁻¹ were filtered at a hydraulic retention time of 2 h through a filtration column packed with the modified biochar, a TP removal efficiency of over 99% and an effluent TP concentration of less than 0.02 mg·L⁻¹ were achieved. The isotherms of the phosphorus adsorption by the modified biochar fitted the Freundlich equation better than the Langmuir equation. The mechanism of the phosphorus adsorbed by the modified biochar was analyzed by using various technologies, i.e. scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis, X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR). The results indicated that the surface of the modified biochar was covered by small iron granules, which were identified as Fe₃O₄. The results also showed that new iron oxides were formed on the surface of the modified biochar after the adsorption of phosphorus. Moreover, new bonds of Fe-O-P and P-C were found, which suggested that the new iron oxides tend to be Fe₅(PO₄)₄(OH)₃. Aside from removing phosphorus, adding the modified biochar into soil also improved soil productivity. When the modified biochar-to-soil rate was 5%, the stem, root, and bean of broad bean plants demonstrated increased growth rates of 91%, 64%, and 165%, respectively.

Keywords

iron-modified biochar / phosphorus removal / agricultural waste / agricultural runoff

References

[1] Wu Y, Hu Z, Yang L, Graham B, Kerr P G. The removal of nutrients from non-point source wastewater by a hybrid bioreactor. Bioresource Technology, 2011, 102(3): 2419–2426

[2] Wang X D, Zhang S S, Liu S L, Chen J W. A two-dimensional numerical model for eutrophication in Baiyangdian Lake. Frontiers of Environmental Science & Engineering, 2012, 6 (6): 815–824

[3] Li L, Li Y, Biswas D K, Nian Y, Jiang G. Potential of constructed wetlands in treating the eutrophic water: evidence from Taihu Lake of China. Bioresource Technology, 2008, 99(6): 1656–1663

[4] Gan L, Zuo J, Xie B, Li P, Huang X. Zeolite (Na) modified by nano-Fe particles adsorbing phosphate in rainwater runoff. Journal of Environmental Sciences-China, 2012, 24(11): 1929–1933

[5] Xie J, Zhang X Y, Xu Z W, Yuan G F, Tang X Z, Sun X M, Ballantine D J. Total phosphorus concentrations in surface water of typical agro- and forest ecosystems in China, 2004–2010. Frontiers of Environmental Science & Engineering, 2014, 8 (4): 561–569

[6] Correll D L. The role of phosphorus in the eutrophication of receiving waters: A review. Journal of Environmental Quality, 1998, 27(2): 261–266

[7] Schauser I, Chorus I, Heinzmann B. Strategy and current status of combating eutrophication in two Berlin lakes for safeguarding drinking water resources. Water science and technology, 2006, 54(11): 93–100

[8] de-Bashan L E, Bashan Y. Recent advances in removing phosphorus from wastewater and its future use as fertilizer (1997–2003). Water Research, 2004, 38(19): 4222–4246

[9] Jaffer Y, Clark T A, Pearce P, Parsons S A. Potential phosphorus recovery by struvite formation. Water Research, 2002, 36(7): 1834–1842

[10] Shanableh A M, Elsergany M M. Removal of phosphate from water using six Al-, Fe-, and Al-Fe-modified bentonite adsorbents. Journal of Environmental Science and Health, Part a—Toxic/Hazardous Substances & Environmental Engineering, 2013, 48(2): 223–231

[11] Posadas E, García-Encina P A, Soltau A, Domínguez A, Díaz I, Muñoz R. Carbon and nutrient removal from centrates and domestic wastewater using algal-bacterial biofilm bioreactors. Bioresource Technology, 2013, 139: 50–58

[12] Li N, Ren N Q, Wang X H, Kang H. Effect of temperature on intracellular phosphorus absorption and extra-cellular phosphorus removal in EBPR process. Bioresource Technology, 2010, 101(15): 6265–6268

[13] Manyà J J. Pyrolysis for biochar purposes: a review to establish current knowledge gaps and research needs. Environmental Science & Technology, 2012, 46(15): 7939–7954

[14] Zhang A, Bian R, Hussain Q, Li L, Pan G, Zheng J, Zhang X, Zheng J. Change in net global warming potential of a rice-wheat cropping system with biochar soil amendment in a rice paddy from China. Agriculture, Ecosystems & Environment, 2013, 173: 37–45

[15] Lehmann J. Bio-energy in the black. Frontiers in Ecology and the Environment, 2007, 5(7): 381–387

[16] Lehmann J. A handful of carbon. Nature, 2007, 447(7141): 143–144

[17] Inyang M, Gao B, Pullammanappallil P, Ding W, Zimmerman A R. Biochar from anaerobically digested sugarcane bagasse. Bioresource Technology, 2010, 101(22): 8868–8872

[18] Laird D A. The charcoal vision: A win-win-win scenario for simultaneously producing bioenergy, permanently sequestering carbon, while improving soil and water quality. Agronomy Journal, 2008, 100(1): 178–181

[19] Glaser B, Lehmann J, Zech W. Ameliorating physical and chemical properties of highly weathered soils in the tropics with charcoal- a review. Biology and Fertility of Soils, 2002, 35(4): 219–230

[20] Zhang M, Gao B, Varnoosfaderani S, Hebard A, Yao Y, Inyang M. Preparation and characterization of a novel magnetic biochar for arsenic removal. Bioresource Technology, 2013, 130: 457–462

[21] Hawn D D, Dekoven B M. Deconvolution as a correction for photoelectron inelastic energy losses in the core level XPS spectra of iron oxides. Surface and Interface Analysis, 1987, 10(2–3): 63– 74

[22] Muhler M, Schlogl R, Ertl G. The nature of the iron oxide-based catalyst for dehydrogenation of ethylbenzene to styrene. Journal of Catalysis, 1992, 138(2): 413–444

[23] Yamashita T, Hayes P. Analysis of XPS spectra of Fe²⁺ and Fe³⁺ ions in oxide materials. Applied Surface Science, 2008, 254(8): 2441–2449

[24] Sun Y P, Li X Q, Cao J, Zhang W X, Wang H P. Characterization of zero-valent iron nanoparticles. Advances in Colloid and Interface Science, 2006, 120(1–3): 47–56

[25] Xie B M, Zuo J N, Gan L L, Liu F L, Wang K J. Cation exchange resin supported nanoscale zero-valent ironfor removal of phosphorus in rainwater runoff. Frontiers of Environmental Science & Engineering, 2014, 8 (3): 463–470

[26] Ismail H M, Cadenhead D A, Zaki M I. Surface reactivity of iron oxide pigmentary powders toward atmospheric components: XPS and gravimetry of oxygen and water vapor adsorption. Journal of Colloid and Interface Science, 1996, 183(2): 320–328

RIGHTS & PERMISSIONS

Higher Education Press and Springer-Verlag Berlin Heidelberg