The Preparation And Characterization Of Diatomite Composite Absorbent And Its Study On The Adsorption Properties

Phosphorus is one of the important causes for the eutrophication waters at homeand abroad in recent years. Therefore the development of the adsorbent material isresearch focus about control of eutrophic.(1) Diatomite was adopted as basic material to develop particle adsorptionmaterials by combining fly ash and steel slag, respectively. Through comparison ofdifferent complementary material, Steel slag was identified as the auxiliary materialused for the preparation of compound adsorption material.(2) Through single factor experiment and orthogonal experiment about preparationconditions, Comprehensive comparison of the analysis results of Strength of materialsand adsorption properties, the optimum preparation process conditions for particleadsorption materials was a mixing ratio of6:4,25%bond material,8%pore-foamingagent, a roasting temperature of700℃, a roasting time of120min.(3) The optimum conditions that the particle adsorption materials removedphosphorus in wastewater were that the adsorption temperature of25℃, the usage ofadsorption materials was22.5g/L, pH=7, the adsorption time of960min, phosphorusremoval rate is the best.(4) Through the static leaching experimental of the composite adsorption material,the stability and amount of releasing alkalinity and calcium ions influencedephosphorization effect. The dynamic analysis of releasing calcium ions about thecomposite adsorption material shows that the process is the slow reaction diffusion.(5) The thermodynamics and dynamic adsorption experiments results showed thatthe pseudo second order reaction and Langmuir equation would describe the phosphorusadsorption process of particle adsorption materials more accurately, it is theendothermic and spontaneous reaction. Physical adsorption and chemical adsorptionare exist at the same time, the chemical adsorption Generate calcium phosphate precipitation Is a major role. Desorption rate is very low in distilled water after theadsorption saturation, the phosphorus absorption stability of Mmaterials is good.Desorption rate can reach more than70%in3%hydrochloric acid solution, the resultsshow that the materials can be recycled after the absorption of phosphorus.