Adsorption of Cr(VI) with Activated Carbon Species Obtained from Waste Cigarette Butts

Project no. 32584 · Status: Kapanmış (Yayın bekleniyor) · 2024

Summary

<p>Water&nbsp;is&nbsp;one&nbsp;of&nbsp;the&nbsp;most&nbsp;essential&nbsp;natural&nbsp;resources&nbsp;that&nbsp;must&nbsp;be&nbsp;protected,&nbsp;as&nbsp;it&nbsp;is&nbsp;indispensable&nbsp;for&nbsp;the&nbsp;survival&nbsp;of&nbsp;all&nbsp;living&nbsp;organisms&nbsp;on&nbsp;Earth.&nbsp;Today,&nbsp;population&nbsp;growth&nbsp;and&nbsp;technological&nbsp;development&nbsp;have&nbsp;led&nbsp;to&nbsp;an&nbsp;increase&nbsp;in&nbsp;water&nbsp;pollution&nbsp;caused&nbsp;by&nbsp;domestic,&nbsp;industrial,&nbsp;and&nbsp;agricultural&nbsp;wastes.&nbsp;In&nbsp;particular,&nbsp;the&nbsp;rapid&nbsp;development&nbsp;of&nbsp;industries&nbsp;such&nbsp;as&nbsp;mining,&nbsp;metallurgy,&nbsp;textiles,&nbsp;and&nbsp;chemicals&nbsp;has&nbsp;resulted&nbsp;in&nbsp;wastewater&nbsp;containing&nbsp;heavy&nbsp;metals&nbsp;becoming&nbsp;one&nbsp;of&nbsp;the&nbsp;most&nbsp;significant&nbsp;environmental&nbsp;problems.</p><p>Heavy&nbsp;metals&nbsp;can&nbsp;persist&nbsp;in&nbsp;the&nbsp;environment&nbsp;for&nbsp;long&nbsp;periods&nbsp;and,&nbsp;due&nbsp;to&nbsp;their&nbsp;bioaccumulative&nbsp;nature,&nbsp;may&nbsp;cause&nbsp;toxic&nbsp;effects&nbsp;and&nbsp;even&nbsp;mortality&nbsp;in&nbsp;humans&nbsp;and&nbsp;aquatic&nbsp;ecosystems.&nbsp;Therefore,&nbsp;the&nbsp;removal&nbsp;of&nbsp;heavy&nbsp;metals&nbsp;from&nbsp;aqueous&nbsp;environments&nbsp;is&nbsp;of&nbsp;great&nbsp;importance.&nbsp;Another&nbsp;major&nbsp;environmental&nbsp;issue&nbsp;is&nbsp;cigarette&nbsp;butts,&nbsp;which&nbsp;are&nbsp;discarded&nbsp;by&nbsp;millions&nbsp;of&nbsp;people&nbsp;worldwide.&nbsp;Cigarette&nbsp;butts&nbsp;contain&nbsp;more&nbsp;than&nbsp;4,000&nbsp;toxic&nbsp;chemical&nbsp;compounds&nbsp;and&nbsp;release&nbsp;heavy&nbsp;metals&nbsp;and&nbsp;harmful&nbsp;substances&nbsp;into&nbsp;the&nbsp;environment&nbsp;during&nbsp;degradation.&nbsp;This&nbsp;situation&nbsp;highlights&nbsp;the&nbsp;necessity&nbsp;of&nbsp;proper&nbsp;disposal&nbsp;and&nbsp;management&nbsp;of&nbsp;cigarette&nbsp;butts.</p><p>Chromium&nbsp;is&nbsp;an&nbsp;important&nbsp;heavy&nbsp;metal&nbsp;widely&nbsp;used&nbsp;in&nbsp;steel&nbsp;plating,&nbsp;leather&nbsp;tanning,&nbsp;and&nbsp;many&nbsp;other&nbsp;industrial&nbsp;applications.&nbsp;The&nbsp;amount&nbsp;of&nbsp;chromium&nbsp;discharged&nbsp;into&nbsp;the&nbsp;environment&nbsp;through&nbsp;wastewater&nbsp;poses&nbsp;a&nbsp;serious&nbsp;environmental&nbsp;concern.&nbsp;In&nbsp;aqueous&nbsp;systems,&nbsp;chromium&nbsp;exists&nbsp;mainly&nbsp;in&nbsp;trivalent&nbsp;[Cr(III)]&nbsp;and&nbsp;hexavalent&nbsp;[Cr(VI)]&nbsp;forms.&nbsp;While&nbsp;Cr(III)&nbsp;is&nbsp;an&nbsp;essential&nbsp;trace&nbsp;element&nbsp;for&nbsp;living&nbsp;organisms,&nbsp;Cr(VI)&nbsp;is&nbsp;inherently&nbsp;toxic&nbsp;and&nbsp;carcinogenic.</p><p>In&nbsp;this&nbsp;study,&nbsp;activated&nbsp;carbon&nbsp;was&nbsp;produced&nbsp;from&nbsp;waste&nbsp;cigarette&nbsp;butts&nbsp;using&nbsp;the&nbsp;pyrolysis&nbsp;method.&nbsp;A&nbsp;portion&nbsp;of&nbsp;the&nbsp;obtained&nbsp;activated&nbsp;carbon&nbsp;was&nbsp;modified&nbsp;by&nbsp;reducing&nbsp;iron&nbsp;metal&nbsp;to&nbsp;its&nbsp;zero-valent&nbsp;state,&nbsp;resulting&nbsp;in&nbsp;the&nbsp;preparation&nbsp;of&nbsp;two&nbsp;different&nbsp;adsorbents.&nbsp;The&nbsp;Cr(VI)&nbsp;removal&nbsp;performances&nbsp;of&nbsp;these&nbsp;adsorbents&nbsp;were&nbsp;comparatively&nbsp;evaluated.&nbsp;The&nbsp;structural&nbsp;and&nbsp;surface&nbsp;characteristics&nbsp;of&nbsp;the&nbsp;adsorbents&nbsp;were&nbsp;characterized&nbsp;using&nbsp;SEM-EDX,&nbsp;BET,&nbsp;XPS,&nbsp;and&nbsp;FT-IR&nbsp;analyses.</p><p>The&nbsp;optimum&nbsp;adsorption&nbsp;conditions&nbsp;for&nbsp;Cr(VI)&nbsp;removal&nbsp;were&nbsp;determined&nbsp;by&nbsp;considering&nbsp;parameters&nbsp;such&nbsp;as&nbsp;pH,&nbsp;adsorbent&nbsp;dosage,&nbsp;and&nbsp;contact&nbsp;time.&nbsp;In&nbsp;addition,&nbsp;isotherm,&nbsp;kinetic,&nbsp;and&nbsp;thermodynamic&nbsp;analyses&nbsp;were&nbsp;conducted&nbsp;to&nbsp;elucidate&nbsp;the&nbsp;adsorption&nbsp;mechanism.&nbsp;Regeneration&nbsp;and&nbsp;interference&nbsp;experiments&nbsp;were&nbsp;also&nbsp;performed&nbsp;to&nbsp;evaluate&nbsp;the&nbsp;selectivity&nbsp;and&nbsp;reusability&nbsp;of&nbsp;the&nbsp;adsorbents.</p><p>In&nbsp;this&nbsp;study,&nbsp;activated&nbsp;carbon&nbsp;derived&nbsp;from&nbsp;cigarette&nbsp;butts&nbsp;was&nbsp;utilized&nbsp;for&nbsp;heavy&nbsp;metal&nbsp;adsorption.&nbsp;The&nbsp;fact&nbsp;that&nbsp;activated&nbsp;carbon&nbsp;obtained&nbsp;from&nbsp;cigarette&nbsp;butts&nbsp;has&nbsp;not&nbsp;previously&nbsp;been&nbsp;used&nbsp;for&nbsp;Cr(VI)&nbsp;removal&nbsp;within&nbsp;this&nbsp;scope&nbsp;demonstrates&nbsp;the&nbsp;originality&nbsp;of&nbsp;the&nbsp;present&nbsp;study.</p>

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