en عمومى General مقاله اصیل Original Article <div style="text-align: justify;"><span class="fontstyle0">Background: </span><span class="fontstyle2">Leachate contains toxic and non-biodegradable substances that are not easily treated by conventional treatment methods. This study investigated the effect of pH, current density, and reaction time parameters on the removal of cyanide (CN</span><span class="fontstyle2" style="font-size:5pt;">-</span><span class="fontstyle2">), nitrate (NO3</span><span class="fontstyle2" style="font-size:5pt;">-</span><span class="fontstyle2">), turbidity, and chemical oxygen<br> demand (COD) from leachate by electrocoagulation process.</span><br> <span class="fontstyle0">Methods: </span><span class="fontstyle2">This study was an experimental one with direct current using four parallel bipolar aluminum electrodes with 90% purity. The length, width, and thickness of the electrodes were 5 cm, 10 cm, and 2 mm, respectively. There were 6 holes with a diameter of 0.7 cm on each of the electrodes. The samples were prepared from the old leachate of solid waste landfill in Ghaemshahr, Iran.</span><br> <span class="fontstyle0">Results: </span><span class="fontstyle2">In this study, at a current density of 33 mA/cm</span><span class="fontstyle2" style="font-size:5pt;">2 </span><span class="fontstyle2">and a time of 60 minutes, the optimum removal efficiency of cyanide (100 %) was obtained at pH 5.5 and pH 10. Moreover, the maximum removal of nitrate (99.65 %) and turbidity (86.41 %) were at pH 5.5 and pH 8.3, respectively and the highest removal efficiency of COD (83.14 %) was obtained at pH 10.</span><br> <span class="fontstyle0">Conclusion: </span><span class="fontstyle2">The results showed that the removal of cyanide, nitrate, turbidity, and COD increases with increasing current density and reaction time. Due to the proper removal of nitrate and cyanide from leachate by electrocoagulation, nitrate and cyanide amounts were less than the allowable contamination level. Based on the results, electrocoagulation is considered an efficient and effective method for removing nitrate and cyanide from old leachate of municipal solid wastes.</span></div> Electrocoagulation, Cyanides, Nitrates, Chemical oxygen demand analysis, Solid waste 237 244 http://ehemj.com/browse.php?a_code=A-10-1-220&slc_lang=en&sid=1 Abdoliman Amouei iamouei1966@gmail.com 10031947532846008877 10031947532846008877 No Environmental Health Research Center (EHRC), Social Determinants of Health Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran Mehdi Pouramir pouramirm@yahoo.com 10031947532846008878 10031947532846008878 No Clinical Biochemistry Department, Babol University of Medical Sciences, Babol, Iran Hosseinali Asgharnia ehaamin2@gmail.com 10031947532846008879 10031947532846008879 No Environmental Health Research Center (EHRC), Social Determinants of Health Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran Mahmoud Mehdinia smehdinia@yahoo.com 10031947532846008880 10031947532846008880 No Environmental Health Research Center (EHRC), Social Determinants of Health Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran Mohammad Shirmardi shirmardim@yahoo.com 10031947532846008881 10031947532846008881 No Environmental Health Research Center (EHRC), Social Determinants of Health Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran Hourieh Fallah fallah_1347@yahoo.com 10031947532846008882 10031947532846008882 No Environmental Health Research Center (EHRC), Social Determinants of Health Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran Asieh Khalilpour Asieh.khalilpour@gmail. com 10031947532846008883 10031947532846008883 Yes Corresponding author:Environmental Health Research Center (EHRC), Social Determinants of Health Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran Hajar Tabarinia tabariniah@yahoo.com 10031947532846008884 10031947532846008884 No Water Wastewater Chemistry Laboratory, Environmental Health Department, Babol University of Medical Sciences, Babol, Iran