| The calcareous mineral is abundant, that make it hopeful to be one effective and low-cost adsorbent. However, the adsorption properties of natural calcareous mineral are poor, need to be activated.In this paper, we choose the calcareous mineral as raw material, the activated adsorbent was developed under certain specified technique, which improved the adsorption capability for azo-dyes. So we try to develop a new adsorption material of low cost and easy availability, no secondary pollution and be recycleable. Hence, the materials characterization and dye-adsorption property to the dye-adsorption theory and recycleable, retread sorbent was carried out. The study has value for plenary calcareous mineral resource in our country, also it can improve the treatment efficiency and reduce the treatment cost of dye wastewater. The main achievements are as follows:1.XRD, FTIR, SEM and TEM technologies were adopted to characterize and analyse the crystal and molecular configurations and surface appearances of the calcareous mineral and actived adsorbent. The research shows that the decolorization rate of calcareous mineral on dyes were very low, the material structure was changed when the calcareous mineral was calcined at 800℃, with the specific surface area(SBET)increasing from 18.35 to 24.43 m2·g-1, the decolorization rate increasing from 6.5% to 99.02%.2.The effects of adsorbent concentration, adsorption time, pH value, dyes concentration, dyes structure and dyes amount on the dyes adsorption of activated calcareous adsorbent were analyzed. The results shown that the rate of decolorization of activated calcareous adsorbent is 99.33%, COD removal rate is 55% ammonia-nitrogen content is about 4.0 mg·L-1, when the pH is 7 for acid fuchsin dye, concentration is 10mg/L to initial dye, dosage of adsorbent is 10g / L, initial COD is 103.5 mg·L-1, adsorbed 5min. The behavior and mechanism of adsorption was discussed for different dyes structural and dyes amount. The research will be shown an very important applicability worthiness to set up a society of save resource and friendly environment. The pH value, dyes concentration and dyes structure were the main factors influencing adsorption process.3.The recycleable and regenerative repair of saturation adsorbent was studied. The results shown that the separation of mushy stage existing in the process when control granularity can be solved effectively by using the decolorizing ceramsite treatment. Under low concentration, the rate of decolorization of activated calcareous adsorbent decreased by 26.9%, COD removal rate decreased by 32.5% when adsorption 7 times; the adsorption times decreases 7 to 5 as the concentration rises. It showed the good repair and regeneration property of calcareous sorbents when regeneration temperature at 650℃, the rate of decolorization of calcareous adsorbent increased 26.9% to 99.01%.4.The adsorption isotherms model, kinetics model and thermodynamic parameter of dyes onto calcareous adsorbent was firstly studied and its dyes adsorptionmechanisms were then proposed in the paper. The adsorption isotherms were studiedusing Langmuir and Freundlich models. It showed that the Freundlich model was thebest one. The adsorption process of AF dye can be better described by the pseudo-second-order model, and the DB dye described by the pseudo-first-order model. And the adsorption mechanisms of dyes were proposed as:adsorption by an electrostatic force, hydrogen bond, n-πinteraction and Van der Waals force,of which the hydrogen bond was the main effects.
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