حذف بنزن از محيط هاي آبي با استفاده از نانو زيست جاذب اصلاح شده با نانو ذرات آهن صفر ظرفيتي

چكيده انگليسي :

94 Removal of Benzene form Aqoueous Solution by Nano Bioadsorbent Modified with Nano Zero Valent Iron Zahra Iravani Mohammad abadi z iravani@ag iut ac ir December 16 2013 Department of Water Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language FarsiJ Abedi Koupai koupai@cc iut ac ir AbstractEnvironmental contamination attributed to the presence of organic and inorganic pollutants is one ofthe major problems in the world Benzene is an organic chemical compound with the molecularformula C6H6 It is a natural constituent of crude oil and is one of the most elementarypetrochemicals Benzene can enter the human organism through inhalation ingestion or skin contactand may accumulate in bones brain kidney causing serious damage to the kidney liver and nervoussystem It causes anemia cancer and sometimes even death Due to the dangerous effects of benzeneit is essential to check waste streams containing benzene before being discharged into the waterresources The maximum permissible limit assigned by World Health Organization WHO forbenzene in drinking water is 0 001 mg L WHO 1996 In recent years attempts are therefore beingmade to develop inexpensive adsorbents utilizing abundant natural materials Agricultural wastematerials often employed as adsorbent may have potential marketing preference for wastewatertreatment among other adsorbent types due to the low cost environmentally friendly naturallyaccessible and efficient Using zero valent iron nanoparticles nZVI has attracted attentions in thefield of environmental pollution For this purpose using nZVI as one of the recent new technologiescan be useful These particles are very reactive as their sizes are very small nZVI effectively reducesorganic and inorganic pollutants but their mobility and lifetime are limited In this study the ashcone pine APC and ash modified with nano zero valent iron APC nZVI were used for removal ofbenzene from aqueous solutions Techniques such as XRD FTIR SEM and EDX were used tocharacterize the adsorbent attribute of the APC and APC nZVI and its ability as an adsorbent whilevariable initial concentration of benzene the amount of adsorbent contact time temperature andpollutant s solution pH were investigated Isotherm models Langmuir and Freundlich were fitted tobenzene adsorption equiblirium data Kinetic models pseudo first order pseudo second order intraparticle diffusion and power function were used to describe kinetic data of benzene adsorption Optimum benzene adsorption was observed at pH 7 and optimum amount of adsorbent 0 1 g forAPC and APC nZVI The observed equilibrium time on APC and APC nZVI was 10 min and 300min respectively while the equilibrium adsorption capacities were 366 mg g and 392 mg g at 2000mg L initial benzene concentration Linear and non linear isotherm studies showed that equilibriumdata better fitted for APC to Langmuir and for APC nZVI to Freundlich isotherm model Kineticstudies showed better applicability of pseudo second order kinetics model It was concluded thatAPC nZVI showed better performance for benzene removal compared to APC To complete thestudies on the introduced adsorbent column adsorption experiments were performed to check theabsorbent performance during continuously injected benzene solution into the adsorbent column until the adsorbent has been saturated The results for columns with continuous inflow indicated thatthe maximum capacity of adsorption of benzene for adsorbent column with diameter of 3cm andinput concentration of 1000 mg L and input rate of 100 mL h for APC and APC nZVI was 295mg g and 392 mg g The results of this experiment showed that APC and APC nZVI has highcapability for removal benzene from equeous solutions Keywords Benzene Ash pine cone Nano zero valent iron Adsorption Batch adsorption Column experiment

ايرواني محمدآبادي، زهرا

حذف بنزن از محيط هاي آبي با استفاده از نانو زيست جاذب اصلاح شده با نانو ذرات آهن صفر ظرفيتي

آلودگي نفتي , مخروط كاج , خاكستر مخروط كاج , آزمايش پيمانه اي , آزمايش ستوني