بررسی تاثیر کاربرد ترکیبی ازن و کربوسیو در حذف کاتالیستی اتیل‌‌بنزن از جریان هوای آلوده

نویسندگان
دانشکده بهداشت همدان
چکیده
مقدمه

اتیل‌‌بنزن یکی از مهم‌‌ترین ترکیبات آلی فرار و یکی از 189 ماده خطرناک آلاینده هوا است که وجود آن در هوای فضاهای بسته و باز مورد توجه بوده و همواره نگرانی‌‌هایی را در آلودگی هوا بوجود آورده است. بنابراین بایستی قبل از انتشار به محیط زیست از جریان هوای آلوده تصفیه شود. این مطالعه با هدف تاثیر کاربرد ترکیبی ازن و کربوسیو در حذف کاتالیستی اتیل‌‌بنزن از جریان هوای آلوده انجام شده است.

مواد و روش‌‌ها

این مطالعه از نوع تجربی بود که در آن از ترکیب ازن و کربوسیو به عنوان کاتالیزور جهت حذف‌‌اتیل‌‌بنزن از جریان هوا استفاده شد. آزمایشات مربوطه در یک راکتور با جریان مداوم انجام شد و نتایج از‌‌ن‌‌زنی کاتالیزوری با ازن‌‌زنی ساده و جاذب کربوسیو مقایسه گردید. نمونه برداری و آنالیز نمونه‌‌ها با روش NMAM 1501 با استفاده از دستگاه GC مجهز به آشکارساز FIDانجام شد.

یافته‌‌ها

یافته‌‌های مورد بررسی نشان داد کارایی فرآیند ازن‌‌زنی ساده در حذف اتیل‌‌بنزن از جریان هوای آلوده در غلظت‌‌های مورد مطالعه به طور متوسط کمتر از 25% می‌‌باشد. همچنین کارایی بستر جاذب کربوسیو با افزایش غلظت آلاینده در ورودی راکتور کاهش می‌‌یابد. در فرآیند از‌‌ن‌‌زنی کاتالیزوری نسبت به جاذب کربوسیو بطور میانگین در تمامی غلظت‌‌ها افزایش راندمان 45% مشاهده گردید.

نتیجه‌‌گیری

با توجه به عملکرد فرآیند ترکیبی ازن و کربوسیو و افزایش راندمان حذف اتیل‌‌بنزن در مقایسه با فرآیند از‌‌ن‌‌زنی ساده و سیستم جاذب کربوسیو کاربرد این فرآیند به عنوان روشی نوید بخش و جایگزین سیستم‌‌های رایج حذف ترکیبات آلی فرار پیشنهاد می‌‌گردد.
کلیدواژه‌ها

عنوان مقاله English

The Study of Effect the Combined Use of Ozone and Carbosieve in the Catalytic Removal of Ethylbenzene from the Polluted Airstream

نویسندگان English

mohammad reza samarghandi
ghorban asgari
farshid ghorbani
seyed alireza babaee
hamadan
چکیده English

Introduction and Aims: Ethylbenzene is one of the most important volatile organic compounds and one of 189 hazardous air pollutants that found in many indoor and outdoor environments and always creates air pollution concerns. Thus, before being discharged to the environment, it must be treated from polluted airstream. The aim of this study was the effect of combined use of ozone and carbosieve in the catalytic removal of ethylbenzene from the polluted airstream.

Materials & Methods: The study was experimental in which a combination of ozone and carbosieve as a catalys was used in the removal of ethylbenzene from the polluted airstream. The experiments were carried out in a reactor with the continuous system and the results of catalytic ozonation were compared with the results of single ozonation and carbosieve adsorbent. The sampling and analyzing were done with 1501 NMAM method by GC equipped with FID detector.

Results: The results of this study showed that the removal effectiveness of single ozonation process is averagely less than 25%. Also, the efficiency of absorbent decreased with the concentration increase of ethylbenzene.The increase ratio of the efficiency in catalytic ozonation process to efficiency of carbosieve adsorbent was averagely 45%.

Conclusion: With regard to high efficiency of catalytic ozonation process and increasing the removal ethylbenzene, the catalytic ozonation process is suggested as a promising and alternative technology for the elimination of VOCs from the polluted air stream.

کلیدواژه‌ها English

Air Pollution
Carbosieve
Ethylbenzene
Ozone
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