Fabrication of porosity-enhanced MgO/biochar for removal of phosphate from aqueous solution: Application of a novel combined electrochemical modification method

Bioresour Technol. 2016 Jan:200:1029-32. doi: 10.1016/j.biortech.2015.10.008. Epub 2015 Oct 10.

Abstract

A novel combined electrochemical modification (CEM) method, using a graphite electrode-based electric field and MgCl2 as electrolyte, was newly developed to prepare porosity-enhanced biochar containing periclase (MgO) nanocomposites (PE-MgO/biochar). During the CEM method, the dried marine macroalgae was immersed in the MgCl2 solution, and a voltage of 20V was then applied for 10min prior to pyrolysis. Morphological and chemical analyses results showed that nano-sized MgO particles with a highly crystalline structure were dispersed and enriched on the surface of the PE-MgO/biochar, which enabled higher phosphate adsorption capability. In an adsorption equilibrium test, among various biochars, PE-MgO/biochar exhibited the highest phosphate adsorption capacity from aqueous solution with a Langmuir-Freundlich maximum adsorption capacity as high as 620mg-Pg(-1). It can be concluded that the newly introduced CEM method is a potent additional technique to effectively prepare modified-biochar in terms of a simple and time-saving modification method.

Keywords: Adsorption isotherm; Biochar; Marine macroalgae; MgO; Phosphate.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adsorption
  • Charcoal*
  • Electrochemical Techniques*
  • Electrodes
  • Magnesium Chloride / chemistry
  • Magnesium Oxide / chemistry*
  • Phosphates / isolation & purification*
  • Porosity
  • Seaweed / chemistry*
  • Solutions / chemistry
  • Water Pollutants, Chemical / isolation & purification

Substances

  • Phosphates
  • Solutions
  • Water Pollutants, Chemical
  • biochar
  • Magnesium Chloride
  • Charcoal
  • Magnesium Oxide