كاربرد كمپوست به عنوان جاذب زيستي براي جذب فلزات سنگين و تصفيه شيرابه پسماندهاي شهري

چكيده انگليسي :

93 Use of Compost as a Biosorbent for Heavy Metals Adsorption and Treatment of Municipal Solid Waste Leachate Roghaye Rezaei R Rezaei@in iut ac ir January 30 2012 Department of Natural Resources Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language Farsi N Mirghaffari Mnorolah@cc iut ac ir and B Rezaei rezaei@cc iut ac ir AbstractLeachates contain large amounts of organic matter and compounds such as ammonia nitrogen heavy metals chlorinated organic and inorganic salts Not treatment leachate migration from the landfill to surface andgroundwater could be a potential source of contaminations Various treatment leachate method includebiological treatment aerobic and anaerobic processes and physical and chemical treatment chemicaloxidation adsorption chemical precipitation coagulation occulation sedimentation otation and airstripping have been used to treat land ll leachate Moreover heavy metals are one of the most important anddangerous environmental pollutants because of accumulating in aquatic ecosystem and high toxicitycharacteristics In recent years adsorption process has taken more attention at heavy metals and pollutantstreatment due to high efficiency and approximately low cost At this among low cost adsorbents can beconsidered as one of the widely used process for the removal of heavy metals from the wastewater due to itssimplicity of design easy availability versatility selectivity environmentally friendly method and highremoval efficiency The objective of this study was the adsorption of copper and chromium heavy metals andreduction of organic matter of leachate using production adsorbents from compost to form raw and treatment 300 C and 600 C The adsorption experiments was designed using batch and column techniques and theparameters affecting the sorption including equilibrium time pH initial heavy metals concentration adsorbent amount and its particle size were investigated Some physical chemical and morphologicalproperties of adsorbents were determined by thermal gravimetric analysis fourier transform infraredspectroscopy scanning electron microscopy elemental analysis and experimental analysis Adsorptionkinetics studies showed that the adsorption of copper and chromium heavy metals by raw and treatmentcompost is rapid as to reach equilibrium for copper adsorption was found to be 30 and 15 min for raw and300TC sorbents and 600TC sorbent respectively and for chromium adsorption was 60 min the pseudo firstorder and pseudo second order kinetic data for heavy metals sorption by three adsorbents shown thatpseudo second order model were precisely fitted There was not significant difference 5 in thepercentage of copper removal with an increase of pH from 2 0 to 6 0 The optimum pH for chromiumsorption by adsorbents was 3 0 The isotherms adsorption indicated that the adsorption by raw and treatmentcompost could be well described by Langmuir and Redlich Peterson models for copper and Freundlich andRedlich Peterson models for chromium adsorption Maximum capacity of copper and chromium adsorptionusing adsorbents were forecast 50 and 13 mg g by Langmuir respectively The percentage of copper removalincreased with the increment of the sorbent amount and decrease of particle size Copper desorption byhydrochloric acid and nitric acid were equal for 600 C treatment compost and to survey of adsorbentsefficiency at copper adsorption at column techniques after asid transit from it 5M nitric acid concentrationwere chose The result of this stage shown that column has 70 efficiency of copper adsorption The initialresults of removal organic matter from leachate shown that adsorbents have efficiency of COD adsorption 30 Also to survey the optimum adsorbent amount for reduction of COD from leachate by 600 Ctreatment compost shown that with the increment of the sorbent amount t the percentage of COD removalincreased Therefore achieved to more reduction of leachate COD to be need to more adsorbent amount thatis concei

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كاربرد كمپوست به عنوان جاذب زيستي براي جذب فلزات سنگين و تصفيه شيرابه پسماندهاي شهري

جذب سطحي , تيمار حرارتي , همدماي جذب