Experimental Study On Removal Of Cadmium From Mivro Polluted Water By Natural Zeolite And Artificial Zeolite

In order to remove cadmium pollution in the water,this paper chooses two kinds of natural zeolite and synthetic zeolite filter material as raw material was modified respectively,static adsorption experiments of using a single variable to determine the optimum modification of modified liquid concentration and the best dosage of modified liquid such as main modification technology parameters;And the adsorption time,temperature,pH,adsorbent dosage,and the adsorption of main technical parameters such as saturated adsorption capacity were studied.The results showed that: of the modified natural zeolite and modified synthetic zeolite on adsorption of cadmium pollution in the water effect is better,using 1mol/L sodium hydroxide solution with solid liquid ratio of 1:9g/ml at 50?,120 r/min under the conditions of constant temperature oscillation in 10 h optimal modified natural zeolite,the optimal conditions of adsorption is pH 7,at 25?,and 120 r/min under the condition of constant temperature oscillation 120 min optimal adsorption effect;using1mol/L of potassium chloride solution,solid-liquid ratio 1:10 g/ml to join synthetic zeolite,65 ? water bath heating 5h optimal modification of synthetic zeolite;Potassium chloride modified synthetic zeolite is the optimum adsorption conditions of pH 7,at 25?,120 r/min under the condition of constant temperature oscillation 90min;Chitosan modified synthetic zeolite,the optimal modification conditions is to use2% of dilute acetic acid,at 30 ?,and 120 r/min under the condition of constant temperature range 120 min,chitosan modified synthetic zeolite is the optimum adsorption conditions of pH 7,at 25?,and 120r/min under the condition of constant temperature oscillation 90 min.Using SEM,EDS,ir spectra of natural zeolite,modified natural zeolite,synthetic zeolite,two kinds of modification on the surface properties of synthetic zeolite and characterizing the structure analysis,the results show that compared with natural zeolite,sodium hydroxide modified natural zeolite is before modification level off is smooth,of the modified natural zeolite surface formed many grooves,crystal grain size smaller,crystal particles are reunited or gelatinous mass;The latter silicon aluminum than smaller,sodium hydroxide modified mainly aluminum from the zeolite pulled out,reduce the silica alumina ratio in the filter material,so there are adsorption;Modified zeolite has increased several absorption peak,the sodium hydroxide modified natural zeolite adsorption performance is stronger;Potassium chloride modified synthetic zeolite surface more mass,structure the evacuation,synthetic zeolite modified by chitosan surface is uneven;Two kinds of modified filter material,the crystallization of particles size smaller;Two kinds of synthetic zeolite modified on the surface of the aluminum increased significantly,changes the original artificial zeolite silica alumina ratio,may be two kinds of modified filter material increased tetrahedron unit of [AlO4]5-,by electrostatic attraction effect in addition to cadmium.At the same time,using the Langmuir adsorption isotherm model and Freunlich adsorption isothermal model,of natural zeolite and synthetic zeolite adsorption system fitting analysis,sodium hydroxide modified natural zeolite,potassium chloride and chitosan modified synthetic zeolite modified synthetic zeolite meet the Langmuir and Freunlich adsorption isotherm models,the saturated adsorption capacity is respectively 213?g/g?249?g/g?986?g/g.