Determination of appropriate method for stimating of MTBE sorption by the soil of Tehran oil refinery (Ray city)

Subject Areas : Water and Environment

Mohamad  Nickhah Monfared ¹ (MSC in civil engineering- enviroment, Khajeh nassir university)
Mohamad reza  Sabour ² (Faculty member of civil engineer, Khajeh nassir university)

Received: 2006-12-14 Accepted : 2007-03-19 Published : 2010-03-21

Keywords:

Abstract :

Methyl Tertiary-Butyl Ether (MTBE) is one of the gas additives that can be effective in increasing the octan rating of fuel. EPA (Environmental Protection Agency) has labeled MTBE in carcinogen compounds. This compound can leak into the soil from underground fuel tanks and its chemical and physical properties affords rapid influence. Sorption ability of soil, is so effective in influence of MTBE into the soil and "distribution Coefficient (Kd)" can show this ability. Kd is one of the important effectives that recently lionizes in Environmental Geotechnics and its range is so wide in as much as it can be "0" or "1000" and more; This wide range is important in using numerical models for underground water and contaminant trasformation modeling. In this stusy the real value of sorption has been determined by several sorption tests on MTBE and the soil of Ray city and according this value, various isotherm models was studied to finding the most accurate model for MTBE and this soil. In this study, all of the tests has done according to ASTM standards. Finally it's concluded that all of studied models are appropriate for calculating Kd but in similar cases, we can offer foloing models sequently: Dubinin-Radushkevich Model; Langmuir Model; Freundlich Model; Linear Model. )Mgn�S 0�O cm;margin-bottom:.0001pt;text-align:justify;mso-pagination: none;direction:rtl;unicode-bidi:embed'>در پایان مشاهده شد که هر چهار روش بررسی‌شده، برای تعیین ضریب جذب قابل استفاده‌اند؛ امّا در شرایط مشابه، می‌توان به ترتیب، روش‌های دوبینین-رادوشکویچ، لانگ‌مایر، فرندلیخ و در نهایت ایزوترم خطّی را برای تخمین Kd و فرآیند جذب، پیشنهاد کرد.  

References:

[1] ابوالفضل‌زاده، عماد و گیتی‌پور، سعید؛ 1386؛ «بررسی میزان جذب و نشت MTBE در خاکهای رسی معمولی و اصلاح‌شده»؛ پایان‌نامه‌ی کارشناسی ارشد؛ دانشکده‌ی محیط زیست دانشگاه تهران

[2] محمّد، نیک‌خواه منفرد و محمّدرضا، صبور؛ 1386؛ «شبیه‌سازی و مدلسازی عددی جهت بررسی پراکنش آلاینده‌های هیدروکربنی نفتی از مخازن در خاک»؛ پایان‌نامه‌ی کارشناسی ارشد؛ دانشکده‌ی عمران دانشگاه خواجه نصیرالدّین طوسی

[3]  EPA; Office of Radiation and Indoor Air; August 1999; "UNDERSTANDING VARIATION IN PARTITION COEFFICIENT, Kd, VALUES"; EPA 402-R-99-004A

 [4] http://www.hamshahrionline.ir/News/?id=41720