Study On Modification Of Orange Peel Powder And Adsorption Of Heavy Metal Ions

The content of cellulose was increased by pretreatment before modified orange peel powder,Three kinds of adsorbents were prepared by using tartaric acid,lauric acid and diethylenetriamine pentaacetic acid dianhydride to treat orange peel powder,The fourth adsorbent of orange peel powder modified with chloropropane epoxide and combined with DTPA-?-Fe2O3.The properties of the adsorbent were characterized by FTIR,SEM,TGA,BET method.The effects of the four adsorbents on the adsorption properties of Cu2+ and Ni2+ at different pH,temperature and initial concentration were studied.The adsorption mechanism of heavy metals.the main works listed as following:1.The refined orange peel cellulose was modified with tartaric acid,synthesised of tartrate Orange peel powder cellulose ester adsorbent(TA-COP).Then Cu2+ and Ni2+ were desorbed.The results showed that the amount of pretreated orange peel powder was 1.000 g,the amount of catalyst was 0.2000 g,and when the volume of tartaric acid(90 g/L)was 0.025 L,the reaction time was 600 min and the reaction temperature was 75 ?,the best way to synthesize TA-COP.the adsorption date were analyzed and fitted well by Langmuir equation,The maximum adsorption occured at pH 5.0(Cu2+)and 7.0(Ni2+).At 35?,by Langmuir equation,the maximum adsorption capacity calculated was 166.67 mg/g,for Cu2+ the maximum adsorption capacity was 46.95 mg/g.2.Lauric acid was used to modify the refined orange peel cellulose to obtain lauric acid orange peel cellulose ester(LA-COP).The modified material used to adsorb Cu2+ and Ni2+ions from aqueous single solutions.The result showed that optimum synthesis conditions were as follows:the quantity of orange peel powder was 1.000 g,the amount of cerium sulfate supported bentonite catalyst was 0.2000 g,the reaction temperature was 60 ?,the amount of lauric acid was 2.000 g,the reaction time was 480 min.The adsorption capacity increased with the decreasing of temperature.The maximum adsorption occured at pH 6.0(Cu2+)and 7.0(Ni2+).the adsorption date were analyzed and fitted well by langmuir equation,when the temperture was 25 ?,the maximum adsorption capacity of Ni2+ was 294.12 mg/g,the saturated adsorption capacity of Cu2+ was 546.54 mg/g.3.The DMD-COP adsorbent was synthesized with diethylenetriamine pentaacetic acid dianhydride.The results showed that was the best synthetic condition.the amount of orange peel powder was 1.000 g,the amount of diethyltriamine pentanoacetic anhydride was 2.000 g,the reaction time was 720 min,and the reaction temperature was 70 ?.The maximum adsorption occured at pH 5.0(Cu2+)and 7.0(Ni2+).The adsorption kinetics can be well described by the quasi-second-order kinetic equation.the adsorption date were analyzed and fitted well by langmuir equation,From langmuir equation,At 25? the maximum adsorption capacity of Ni2+ was 120.48 mg/g,the saturated adsorption capacity of Cu2+ was 126.26 mg/g.4.ECH and DTPA-?-Fe2O3 modified orange peel(OP)were prepared to improve its adsorption capacity for heavy metal ion such as Cu2+ and Ni2+ The biosorption of nickel and copper ions from aqueous solution by dried composite particles was studied as function of concentration,pH,temperature and adsorption time,From Langmuir isotherm,the adsorption capacity for Cu2+ and Ni2+ were 107.30 mg/g and 63.69 mg/g,The adsorption of Cu2+ and Ni2+ obey the pseudo-second-order kinetics The metal adsorption date were fitted well with Langmuir isotherms.