Removal Of The PHE In The Water Environment Using Biochar Derived From Nutshells

Phenanthrene is a persistent, difficult biodegradable organic pollutants,which is is also a great harm to human health.therefore,to find an effective way to remove phenanthrene in the water environment has certain practical significance.In this paper, the method of adsorption to removel phenanthrene,the adsorbent is the biochars derived from coconut shell(CNS),almond shell(AS),walnut shell(WNS),pistachio nut shell(PNS),peanut shell(PS) under 600? pyrolysis.The experiments study of the adsorption properties of these adsorbents to phenanthrene.The results show that the experiments consistent with the Freundlich adsorption isotherm model and linear model.The relationship between partition coefficients for five kinds of adsorbent material is WNS>PNS>CNS>AS>PS,and with the higher the temperature, the lower the partition coefficient.Adsorption experiments comply with Pseudo-second-equation and Elovich equation model.Thermodynamic analysis shows that the reactions of the five kinds of adsorbent material adsorption phenanthrene are spontaneous,exothermic,and the physical adsorption. And there is no structural change in the adsorbent surface.It was also explored the effect of time, temperature, pH and temperature on the pyrolysis of adsorption experiments.Within the first 10min,the adsorption rate is fastest compared to other time periods,and gradually stabilized after 90mins.The best adsorption is under the acidic conditions,and with the temperature increased, the adsorption capacity decreased.Before pyrolysis experiments,put the CNS into the autoclave under 140? for 4h,the treated CNS pyrolysis in the muffle furnace under 600?.Adsorption properties of this material is batter than the CNS without any treatment before pyrolysis.The experiment also explored the adsorption characteristics of CNS at different temperatures(500?,600?,700?) on the pyrolysis.With the pyrolysis temperature increased,the adsorption capacity increased,the larger the corresponding partition coefficient,it aslo comply with the Freundlich isotherm model and Pseudo-second-equation and Elovich equation model.