مروری بر جاذب‌ها و نانوجاذب‌های طبیعی کیتوسان مورد استفاده در حذف آلاینده‌های فلزی آب

نوع مقاله: مقالات علمی

نویسندگان

1 کارشناسی ارشد، معاونت پژوهشی جهاد دانشگاهی فارس، شیراز، ایران.

2 کارشناسی ارشد، گروه نانوتکنولوژی، معاونت پژوهشی جهاد دانشگاهی فارس، شیراز، ایران.

10.22112/jwwse.2018.130500.1090

چکیده

آلودگی آب از مهم‌ترین چالش‌های پیش­رو بر سلامتی انسان و محیط زیست است. در این بین آلودگی ناشی از فلزات سنگین به سبب رشد روزافزون صنایع بسیار نگران‌کننده بوده و مورد توجه قرار دارد. فلزات سنگین می‌توانند زمینه­ بروز بسیاری از بیماری­های خطرناک به­ویژه انواع سرطان­ها را فراهم سازند. کیتوسان، نانوذرات کیتوسان و مشتقات آن­ها به‏علت دارا بودن گروه‌های OH و NH2، غیرسمی بودن، قیمت پایین و در دسترس بودن در طی سال‌های اخیر برای جذب سطحی آلاینده‌ها مخصوصاً فلزات سنگین، توجه بسیاری از محققین را به‏خود جلب کرده‌اند. در این مقاله مروری، آماده‌سازی کیتوسان، نانوذرات کیتوسان و انواع کیتوسان اصلاح‌شده بررسی شده و کاربردهای آن در فرایند جذب فلزات سنگین از محلول‌های آبی به‌طور خلاصه آورده شده است. تأثیر پارامترهای تأثیرگذار بر فرایند جذب نظیر بلوری شدن کیتوسان، میزان غلظت جاذب، غلظت اولیه فلزات سنگین، زمان فرایند، pH محلول و دما و همچنین ایزوترم و سینتیک جذب مورد بررسی قرار گرفته­اند. در ادامه روش پاسخ سطح توضیح داده شده و روش‌های متداول برای بهینه‌یابی پارامترهای فرایندی جذب سطحی برای فلزات سنگین استفاده شده است. در نهایت بازیابی جاذب‌های بر پایه کیتوسان و استفاده مجدد از آن‌ها در فرایند جذب نیز مورد ارزیابی قرار گرفته است.

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