Background: Contamination of aquatic habitats due to toxicity and accumulation of heavy metals leading to serious damage to organisms and their advance to the food chain. Chrome is one of these heavy metals for the three and six-valence oxides used in industry. Health risks such as carcinogenic hexavalent chromium have been For this reason, removal and reduction of environment is essential. Target of this study hexavalent chromium biosorption by waste stabilization pond algae is of the aquatic environment.

Methods: This study was a fundamental applied; In this batch reactor, variables Was investigated pH(3,5,7,9,11), Contact time(30,60,120,180,240,300min), The concentration of hexavalent chromium(0.5,1,5mg ) And the concentration of algae(0.25, 0.5, 1, 3g). Liquid mixed municipal wastewater treatment stabilization pond was used for insemination. For the investigate the effects of variables pH, contact time, the concentration of hexavalent chromium values in a 250 ml Erlenmeyer flask prepared and various amounts of dried algae (0.25-0.5-1- 3 g) were added to it. Then became the shakers. After mixing, the filter paper was passed. The lab temperature was centrifuged for min10-5 rpm 2700 rpm. Then it was read at a wavelength absorbed by 540 nm. . Then collected was data to Excel and SPSS software. Finally was used for hexavalent chromium adsorption isotherm model equation of Langmuir and Freundlich.

Results: This study shows that PH, contact time, the concentration of hexavalent chromium and chromium concentrations of algae optimal absorption by algae concentrations, respectively, in5 mg / l, min 120, 0.5 mg / l and is 1gr. Average maximum absorption of chromium Wastewater stabilization ponds by algae 97/2%, respectively. Correlation coefficients absorption curves of these models showed that Cr (VI) adsorption isotherm on wastewater stabilization pond algae follows (= R).

 Conclusion: The results showed that wastewater stabilization pond algae as a biological absorption, very high ability to absorb their hexavalent chromium from aqueous solutions. In addition with advantages such as low cost, no need for skilled workers, low excess Chemical waste sludge, metal restore capabilities have been further considered.