Evaluation of color removal of Methylene blue from aqueous solutions using plant stem ash of Persica

Methylene blue (MB) is the most commonly used substance for dying cotton، wood and silk. On inhalation it can cause difficult breathing، while on the direct contact it may cause permanent injury of the eyes of human and animals، burning sensations، nausea، vomiting، profuse sweating، mental confusion and methemoglobinemia. In the present study، Salvadora persica stem ash was used as a low cost adsorbent for the successful removal of Methylene blue (MB) dye from aqueous solutions. This research is an experimental study that was performed to survey efficiency of the Salvadora persica stem ash on removal of methylene blue from aqueous solutions. The effect of various operating parameters such as initial concentration of dye (20-200 mg L-1)، contact time (5-270 min)، adsorbent dosage (0. 2-10 g L-1) and pH (2-13) was investigated. The findings of this study were showed that the Salvadora persica stem ash was able to remove up to 97% of MB dye (156. 22 mg/g) from solutions with various initial dye concentrations at initial pH 13. Also، the equilibrium data were also fitted to the Langmuir and Freundlich equilibrium isotherm models. It was found that the data fitted to Freundlich (R2=0. 9314) better than Langmuir (R2=0. 8836) model. Finally it was concluded that the Salvadora Persica stem ash can be used for textile industry wastewater treatment.