Sorption Of Naphthalene, Phenanthrene And Pyrene From Water By Modified Peat And Its Mechanism Study

This project used natural peat as basic adsorbent, and modified peat by quaternary ammonium surfactants to product one kind of adsorbent to deal with PAHs in water. Naphthalene (NAP), Phenanthrene (PHN) and pyrene (PYR) were used as PAHs target pollutions in this project. The capacity and principle of adsorption were discussed in this project.The result showed Cation Exchange Capacity (CEC) of peat was improved up to 3.7 times than natural peat by pH=12 NaOH solution.Cetyltrimethyl Ammonium Bromide (CTAB), Cetylpyridinium bromide (HPB) and Tetrabutyl Ammonium Bromide (TBAB) were used as modifers to modify peat. The result showed CTAB had better removal efficiency to NAP, PHN and PYR than TBAB and HPB. CTAB was used as NP modifer to do the further research.The conditions of modification were 35℃,4h and CTAB:Peat (mass ratio)=1.108:1; After optimization, the adsorption capacity of modified peat to NAP, PHN and PYR were 20.5%,32.6%,10.0% higher than natural peat. The adhension order of three PAHs on the material was PYR>PHN>NAP.It was found that pseudo-second-order equation and Freundlich adsorption isotherm provided the best correlation to the adsorption processes; Adsorption process was spontaneous, exothermic and physical reaction, whereΔH was between-11KJ·mol-1 and -54 KJ·mol-1; Distributional effects were the main adsorption effect in adsorption processes.