This study presents new environmentally sound and low-cost yet highly efficient pyroxene (NaFeSi2O6{,} PY){,} known as aegirine{,} nanoparticles. They are applied for the first time for the adsorptive removal of violanthrone-79 (VO-79) which was selected as a model-adsorbing compound to mimic polar heavy hydrocarbons. PY nanoparticles are prepared by a low temperature hydrothermal synthesis route. Controlled particle sizes of PY nanoparticles were synthesized in the range between 1 and 100 nm. Moreover{,} the surface and structure of the PY nanoparticles were modified by partially replacing some of the original atoms{,} like Na{,} Fe or Si{,} by Ce{,} Zr{,} Ni{,} Ca and H to enhance their adsorption capacity towards VO-79. One nanoparticle size was prepared at different synthesis heat-treating times to investigate the stability of the nano-adsorbent. It has been found that PY nanoparticles with particle sizes in the range between 30 and 60 nm have the highest adsorption capacity and affinity towards VO-79. The adsorption capacity of the VO-79 over functionalized PY nanoparticles was increased significantly in the order of PY-H > PY-Ca > PY-Ni > PY-Ce > PY-Zr{,} when compared with unmodified PY nanoparticles. Varying the heat-treating time of synthesis of PY nanoparticles did not affect their size stability and surface properties. Moreover{,} no significant increase towards VO-79 adsorption uptake was detected. The experimental macroscopic adsorption isotherms fit well to the Sips model{,} indicating a heterogeneous adsorption system.

Title

RSC Adv.

Publisher

RSC

Publisher Country

United Kingdom

Publication Type

Prtinted only

Volume

6

Year

2016

Pages

64482-64493