استخراج فلزات سنگين با استفاده از غشاء مايع امولسيوني و كاربرد اين روش در تصفيه پساب صنعتي فولاد مباركه

چكيده انگليسي :

Extraction of Heavy Metals Using Emulsion Liquid Membrane andApplication of this Method to the Wastewater treatment of Mobarakeh Steel Company Hamid Ramezani Pourpenchah H Ramezanipourpenchah@ce iut ac ir February 18 2012 Department of Chemical Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Keyghobad Shams K shams@cc iut ac ir AbstractIn this investigation extraction and enrichment of iridium and silver ions were carried out using emulsionliquid membrane ELM as model compounds from aqueous solutions and separation of heavy metals fromwastewaters from Mobarakeh Steel Company In the ELM system the mass transfer flux is high because oflarge surface to volume ratio This would facilitate extraction of metal and nonmetal ions in ppm ppbconcentrations One of the applications of this method is recovery and reuse of heavy metals from industrialwastewaters Response surface methodology is a powerful tool in minimization of number of experimentsthat involve interactive parameters This technique involves three factorial designs giving number of input independent factors and their corresponding relationship between one or more measured dependentresponses Response surface methodology RSM was used to determine the minimum number ofexperiments in order to study separation of these ions by ELM technique The liquid membrane used wascomposed of liquid paraffin as the solvent sorbitan monooleate SPAN 80 as the surfactant perchloric acidas the internal reagent and Bis 2 ethylhexyl phosphoric acid D2EHPA as the carrier The processparameters namely surfactant concentration carrier concentration contact time external pH speed ofagitation and volume fraction of oil to internal phase on the extraction and enrichment of iridium wereoptimized using Box Behnken design An orthogonal 48 Box Behnken design with six replicates at thecenter point all in duplicates resulting in a total of 54 experiments were used to optimize the chosen keyvariables for maximum amount of the extraction and enrichment and minimum amount of swelling on ELM The results show that the optimal values for surfactant concentration carrier concentration contact time speed of agitation external pH and volume fraction of oil to internal phase of system were 1 59 v v 0 08molar 29 5 min 234 rpm 5 3 and 1 36 respectively At the optimized conditions the maximum iridiumextraction and enrichment and minimum swelling of system were 98 18 13 38 and 11 respectively Theprocess parameters namely surfactant concentration carrier concentration external pH and volume fractionof membrane to external phase on the extraction and enrichment of silver were optimized using Box Behnken design The results show that the optimal values for surfactant concentration carrier concentration external pH and volume fraction of membrane to external phase of the system were 3 28 v v 0 05 molar 6 89 and 0 23 respectively At the optimized conditions the maximum silver extraction and enrichment ofsystem were 96 and 10 3 respectively To evaluate the effectiveness of ELM technique real wastewaterfrom Mobarakeh Steel Company that contains several heavy metal ions was used and optimized conditionsfor metal ion separation was obtained Results pertaining to separation of heavy metals from Mobarakehsteel Co wastewaters show that the optimal values for surfactant concentration carrier concentration volume fraction of internal to oil phase and volume fraction of membrane to external phase of the systemwere 2 v v 0 05 molar 0 7 and 0 2 respectively All in all results of this study demonstrate that ELM is aviable technique for separation of dilute solutions Keywords Emulsion liquid membrane response surface methodology iridium silver Mobarakeh steel co extraction and enrichment

رمضاني پور پنجاه، حميد

استخراج فلزات سنگين با استفاده از غشاء مايع امولسيوني و كاربرد اين روش در تصفيه پساب صنعتي فولاد مباركه

روش رويه پاسخ , ايريديوم , نقره , استخراج و غني سازي