اثر کنترل pH براصلاح الکتروسینتیکی یک خاک ریز بافت آلوده به نفت خام

نوع مقاله : مقاله پژوهشی

نویسندگان

1 پردیس کشاورزی و منابع طبیعی دانشگاه تهران

2 دانشجوی سابق کارشناسی ارشد

3 هیئت علمی سازمان پژوهشهای علمی و صنعتی ایران

چکیده

امروزه آلودگی خاک­های حاوی هیدروکربن­های نفتی از مهم­ترین مشکلات زیست­محیطی به شمار می­رود. به­منظور حذف این ترکیبات از خاک راهکارهای مختلف از جمله استفاده از فرایند الکتروسینتیک بکار می­رود. نتیجة فرایند الکتروسینتیک در خاک حرکت آب، یون­ها و ذرات باردار در اثر ایجاد اختلاف پتانسیل الکتریکی می­باشد. در این پژوهش اثر کنترلpH  در کاتولیت و آنولیت بر فرایند اصلاح الکتروسینتیکی یک خاک رسی آلوده به هیدروکربن­های نفتی به ­طول 30 سانتی­متر، مورد ارزیابی قرار گرفت. بدین منظور دو آزمایش با شرایط بدون کنترل pH و با کنترل pH (در محدوده 6 تا 9) در الکترولیت­ آب مقطر انجام شد. غلظت اولیه هیدروکربن­های نفتی در خاک، پنج درصد در نظر گرفته شد. اندازه­گیری مقدار و نوع هیدروکربن­های نفتی در خاک با استفاده از دستگاه  GC/MS انجام شد. نتایج این بررسی نشان داد در هر دو آزمایش پس از 30 روز با اعمال اختلاف پتانسیل یک  1-Vcm، بیشترین درصد خروج مربوط به نواحی مجاور آند و کمترین جابجایی در میانه ستون مشاهده گردید. میانگین حذف هیدروکربن­های نفتی از ستون آزمایش اول 67/16 درصد و در آزمایش دوم، 5/31 درصد مشاهده شد که بیانگر اهمیت نقش تنظیم pH در فرایندهای اصلاح الکتروسینتیک است. همچنین در آزمایش دوم، بطور میانگین 26% از هیدروکربن­های پارافینی و 37% از هیدروکربن‌های آروماتیک نفتالینی از کل ستون خاک خارج شدند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Effect of pH control on electrokinetic remdiation of a fine textured soil contaminated with crude oil

نویسندگان [English]

  • Mohsen Farahbakhsh 1
  • Hadi Sheikhpoori 2
  • Mehran Kiani Rad 3
1 University College of Agriculture and Natural Resources
2 University College of Agriculture and Natural Resources
3 Science and Industrial Research Organization
چکیده [English]

These days, one of the most important environmental problems is soil pollution due to the contamination by petroleum hydrocarbons. One of the methods for reducing of soil contamination is the use of the electrokinetic process for remediation of hydrocarbons contaminated soils. Electrokinetic process causes the movement of water, ions and charged particles in the soil by electric field voltage. In this study, the effect of pH control in catholyte and anolyte on electrokinetic for removal of petroleum hydrocarbons from a clay soil, was evaluated. For this purpose, two experiments; one without pH control and second with pH control (in the range of 6-9) in electrolytes were carried out. Initial concentration of petroleum hydrocarbons in soil was 5%. The amount and type of petroleum hydrocarbons in the soil samples were measured by GC-MS. The results of both experiments showed that after 30 days, and 1 Vcm-1 electric field voltage, the highest percentage hydrocarbons was near anodes with little movement in the middle column. The average of petroleum hydrocarbons removal of two experiments was 16.67% and 31.5%, respectively. In addition, in the second experiment, about 26% of paraffin hydrocarbon and 37% of naphthalene hydrocarbons were removed from the soil column.

کلیدواژه‌ها [English]

  • Electrokinetic
  • pH Control
  • petroleum hydrocarbons
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