نوع مقاله : مقاله پژوهشی

نویسندگان

گروه مهندسی الیاف، دانشکده مهندسی نساجی، دانشگاه صنعتی اصفهان، اصفهان، ایران

چکیده

در سال‌های اخیر، معرفی فرآیند بازیافت ته سیگارهای استفاده‌شده به‌عنوان یک چالش اصلی برای کاهش آلودگی محیط‌زیست در کل جهان مطرح است؛ بنابراین بدین منظور الیاف کربن فعال (ACFs) به‌وسیله فرآیند پیرولیز/ فعال‌سازی با استفاده از عامل فعال-ساز پتاسیم هیدروکسید (KOH) از ته سیگار تولید شدند. فیلترهای عمل شده در یک کوره تیوپی با نرخ‌های گرمایش مختلف و نگه‌داری به مدت h 1 در دمای °C800 تحت محیط نیتروژن تولید شدند. تأثیرات روش‌های مختلف تولید بر روی ساختار سطحی، ریزساختار و تخلخل ACFs مورد مطالعه قرار گرفتند. ساختار سطحی و تحلیل ریزساختار ACFs نشان دادند که مناطق متخلخل و گروه‌های حاوی اکسیژن (COOH، -OH و C=O) بر روی سطح نمونه‌ها شکل‌گرفته‌اند. با توجه به نتایج به‌دست‌آمده، نمونه-های الیاف کربن تولیدشده دارای ساختار متخلخل با حفظ شکل الیاف است. الیاف کربن فعال با بالاترین مقدار بازده کربنی، سطح مخصوص و حجم کل مناطق متخلخل به ترتیب در 41/29 درصد، m2/g855 و cm3/g7431/0 در نمونه با غلظت g/L10 KOH، نرخ گرمایش °C/min2 و دمای کربنیزاسیون °C800 به‌دست‌آمده است. نمونه‌های ACFs تولیدشده، نرخ و ظرفیت جذب مواد نفتی در سطح بالایی با میزان جذب g/g8-3 در مدت‌زمان s 30 از خود نشان دادند. این مطالعه یک فرآیند مهندسی موفق برای بازیافت ته سیگار به‌وسیله تبدیل آن‌ها به ساختارهای ACFs با استفاده از فرآیند فعال‌سازی شیمیایی جهت کاربرد جذب مواد نفتی ارائه‌شده است.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Structural Engineering of activated carbon fibers derived from cigarette butts for fast oily materials adsorption

نویسندگان [English]

  • Zahra Ranjkesh
  • Fatemeh sadat Mousavi
  • Komeil Nasouri

Department of Textile Engineering, Isfahan University of Technology, Isfahan, Iran

چکیده [English]

Introduction: Smoked cigarette butts are one of the main wastes in urban society. In recent years, the effective recycling process from smoked butts is the main challenge for decreasing worldwide environmental pollution. The cigarette butts consist of a filter, paper, tobacco, and adhesive. The main part of smoked butts is cellulose acetate (CA) fibers. The CA contains a suitable carbon content and recommended precursor for the production of activated carbon fibers. Low-cost activated carbon fibers are synthesized by a carbonization/ activation process derived from smoked cigarette filters, in which potassium hydroxide (KOH) acts as the chemical activation agent. There are no researches on the production of activated carbon fibers from smoked cigarette butts with high specific surface area for fast oily materials adsorption. As a result, the smoked cigarette butts were desired as a proper precursor for oil adsorption.

Materials and Methods: The smoked cigarette butts with brown color are washed with distilled water several times and the additional impurities were separated. The clean cigarette filters were stirred in 10 g/L KOH solution as a chemical activation agent. The KOH- treated filters were added to a tube oven and heated at various rates from 2 to 10 °C/min and held at 800 °C for 1 h under a nitrogen atmosphere. The synthesized activated carbon fibers were rinsed several times with dilute hydrochloric acid solution and distilled water until pH became neutral. The effects of various synthesis procedures on surface morphology, microstructure, and porosity of the synthesized activated carbon fibers were investigated.

Results: The surface morphology and elemental analysis of activated carbon fibers displayed that the porous spots and oxygen-containing groups (COOH, –OH, and C=O) are formed on the surfaces of fibers. The activated carbon fibers samples with increasing activation rates increased the number and size of the damaged surface with continuous fibers morphology. Therefore, decreasing the heating rates increases the surface area and porosity of activated carbon fibers. The obtained results displayed that the synthesized activated carbon fibers have developed porous structures with fibrous shapes. The activated carbon fibers with maximum carbon yield, surface area, and total pore volume of 29.41 %, 855 m2/g, and 0.7431 cm3/g were synthesized at a KOH concentration of 10 g/L, a heating rate of 2 °C/min, and carbonization temperature of 800 °C. The D- and G- bands in Raman spectra are happened at ~ 1330 and ~ 1580 cm-1, respectively. These data are displayed the processing parameters did not change the band positions. The D- and G- bands intensities ratios of activated carbon fibers show an increase with increasing activation rate, which recommends that the amorphous carbons are established in the activated carbon fibers. The surface area, meso- porous contents, and carbonic structure of activated carbon fibers can be controlled with investigation levels of activation rates. The synthesized activated carbon fibers display a very high level oil adsorption rate and capacity with sorption of 3-8 g/g values in 30 s. The oil adsorption capacity and the rate increased with decreasing activation rates and direct relation with carbonic structure and porosity of activated carbon fibers.

Conclusion: This research successfully displayed a facile one-step process for the production of activated carbon fibers from smoked cigarette butts with superior carbonic structure and high specific surface area. Moreover, an engineering process of activated carbon fibers production for the fast oily materials adsorption applications through recycling smoked cigarette butts with chemical activation protocol.

کلیدواژه‌ها [English]

  • Recycling
  • Cigarette butts
  • Carbonization
  • Oil adsorption