عنوان مقاله [English]
The hexavalent chromium is one of the heavy metals that toxic and soluble in water, that amount is exceeded in drinking water in Birjand. On the other hand 80% of the pine trees of green space Birjand. This study to remove of hexavalent chromium from aqueous solution by pine fruit powder has been done. The adsorbent prepared in laboratory scale and pulverized by standard ASTM sieve (100 meshes). In this research, the effect of pH, contact time, adsorbent dose, initial Cr (VI) concentration and Temperature and also Langmuir and Freundlich isotherm models was studied. The results showed that increasing the pH and initial chromium concentration led to reducing of the removal efficiency and increasing contact time, adsorbent dose and Temperature led to increasing of removal efficiency. The chromium ions adsorption by pine fruit powder is follows Langmuir isotherm model and also pine fruit powder is suitable natural adsorbent for the removal of chromium (VI).