Abstrato

Removal of methylene blue dye from aqueous solution by sorption onto leaves, flowers and bark of Delonix regia

GhulamShabir, MuhammadAfzal, FarooqAnwar, ZafarM.Khalid, QaiserM.Khan, MuhammadUmarKhan, Zahid Iqbal Sajid

The contamination ofwaterwith dyes is one of themain problems all over theworld. In recent years, concentrated efforts have beenmade to develop an efficient, cost-effective andenvironmentallyfriendly technologyfor the cleanup ofwater pollutedwith dyes. The current studywas undertaken to assess the potential of leaves, flowers and bark ofDelonix regia as adsorbent to clean up thewater pollutedwithmethylene blue dye.Different conditions, such as pHof aqueous solution, amount of adsorbent, agitation time and dye concentration,wereoptimizedtogetmaximumremoval ofmethylene blue fromaqueous solution.The data obtained indicatedthat leaves performed better than flowers and bark as an adsorbent of methylene blue. The highest levels of removal of dye byleaves, flowers and bark were 92.2 %, 82.5 % and 69.2 %, respectively. Similarly,moreCODreductionwas observedbyleaves than flowers and bark. The equilibriumdatawas best fittedwiththeLangmuir adsorptionisothermmodels. In particular, adsorption process was best depicted by pseudo second orderkinetics.This is the first report that leaves, flowers and bark ofDelonix regiawere able to cleanwaterpollutedwithmethylene blue.Although different parts of Delonix regia showed potential to removemethylene blue fromwater, pHofwater, amount of adsorbent, agitation time and dye concentration can affect the efficiencyof adsorption ofplantmaterial