Surfactant-modified zeolite as a slow release fertilizer for phosphorus

J Agric Food Chem. 2006 Jun 28;54(13):4773-9. doi: 10.1021/jf060034b.

Abstract

The feasibility of using surfactant-modified zeolite (SMZ) as a carrier for fertilizer and for slow release of phosphorus (P) was investigated. Zeolite-A was modified by using hexadecyltrimethylammonium bromide, a cationic surfactant, to modify its surface to increase its capacity to retain anion, namely, phosphate (PO4(3-)). SMZ was thoroughly characterized using X-ray diffraction, Fourier transform infrared, and scanning electron microscopy to study the effect of surfactant modification. Zeolite-A and SMZ were then subjected to P loading by treating them with fertilizer (KH2PO4). It was observed that the P loading on SMZ increased by a factor of 4.9 as compared to the unmodified zeolite-A. A comparative study of the release of P from fertilizer-loaded unmodified zeolite-A and SMZ and from solid KH2PO4 was performed using the constant flow percolation reactor. The results show that the P supply from fertilizer-loaded SMZ was available even after 1080 h of continuous percolation, whereas P from KH2PO4 was exhausted within 264 h. The results indicate that SMZ is a good sorbent for PO4(3-), and a slow release of P was achievable. These properties suggest that SMZ has a great potential as the fertilizer carrier for slow release of P.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adsorption
  • Cetrimonium
  • Cetrimonium Compounds / chemistry
  • Fertilizers*
  • Microscopy, Electron, Scanning
  • Phosphorus / administration & dosage*
  • Spectroscopy, Fourier Transform Infrared
  • Surface-Active Agents / chemistry*
  • X-Ray Diffraction
  • Zeolites / administration & dosage
  • Zeolites / chemistry*

Substances

  • Cetrimonium Compounds
  • Fertilizers
  • Surface-Active Agents
  • Zeolites
  • Phosphorus
  • Cetrimonium