تسریع رنگزدایی فرایند فتوکاتالیستی تثبیت‌شده توسط اسکاونجر حفره EDTA

نوع مقاله: مقاله پژوهشی

نویسندگان

1 دانشجوی کارشناسی ارشد عمران و محیط زیست، دانشگاه تربیت مدرس، تهران

2 دانشیار، دانشکده مهندسی عمران و محیط زیست، دانشگاه تربیت مدرس، تهران

چکیده

در این پژوهش اثر اسکاونجر حفره EDTA در تسریع رنگبری رنگزای آبی مستقیم 71 به‌عنوان یک آلاینده سخت تجزیه‌پذیر در فرایند فتوکاتالیستی با استفاده از نانو ذرات دی‌اکسید تیتانیوم پوشش داده شده بر بستر سیمانی بررسی شد. با استفاده از 03/0 مولار EDTA، 75 میلی‌گرم در لیتر رنگزا در pH برابر 6 ، تحت تابش لامپ UV-C  60 وات طی مدت زمان 75 دقیقه رنگبری شد. این درحالی است که رنگزا تحت این شرایط و بدون حضور اسکاونجر در مدت زمان 225 دقیقه حذف شد، به ‌این ترتیب اثر تسریع‌کنندگی این اسکاونجر تأیید شد. سینتیک فرایند فتوکاتالیستی در حضور EDTA مرتبه اول با ثابت واکنش 05/0 بر دقیقه به‌دست آمد که 5/2 برابر سرعت واکنش بدون اسکاونجر بود.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Using the EDTA Hole Scavenger to Accelerate Decolorization in the Immobilized Photocatalytic Process

نویسندگان [English]

  • raziye Asgari 1
  • Bita Ayati 2
1 MSc Student of Civil and Environmental Engineering, Tarbiat Modarres University, Tehran
2 Assoc. Prof. of Civil and Environmental Engineering, Tarbiat Modarres University, Tehran
چکیده [English]

This study investigated the effect of EDTA as a hole scavenger on accelerating the photocatalytic decolorization of direct blue 71 as a non-degradable model pollutant with nano TiO2 powder immobilized on a cementitious bed. For this purpose, 75 mg/L of the dye was decolorized in 75 minutes with 0.03 M of EDTA at a pH level of 6 and under irradiation produced by a 60-W UV-C lamp. This is while decolorization under identical conditions but in the absence of EDTA had been accomplished in 225 minutes. The experiment, therefore, confirmed the accelerating effect of the scavenger on decolorization. The kinetics of the photocatalytic process with EDTA followed a first order reaction with a constant rate of 0.05 min-1, which is 2.5 times faster than the process without EDTA.

کلیدواژه‌ها [English]

  • Kinetics
  • concentration
  • pH
  • Irradiation intensity
  • Direct Blue 71

 

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