Al-MCM-41Synthesized By Coal-series Kaolin And Study On Adsorption Performance After Modifying

Coal-series kaolin as raw material synthesised mesoporous molecular sieves Al-MCM-41whose water thermal stability was higher than MCM-41synthesised bysodium silicate as raw material, and the pore wall thicker. In this paper, we study thefeasibility and technology conditions of preparation of Al-MCM-41by coal measureskaolin, and then apply it to study. Acid treatment can get different Si/Al ratiomolecular sieve characterized by XRD, BET, TEM. Al48-M41owned the highestsurface and the typical hexagonal mesoporous. The channel of Al48-M41is moreregular than the others. The molecular sieve of Si/Al=1synthesised without acidtreatment. It was first successful synthesized. Crystallization time and alkalinity hadinfluence on Al7-M41synthetic. The crystallization time of36h and24h both cansuccessfully synthesize the Al7-M41observing from XRD spectrum diagram.However, we choose the best crystallization time for24h from the economics toconsider. And alkalinity at1.65is the best. Below or above the1.65alkalinity gettingmolecular sieves are not very good. We have the best synthesis condition what is inthe basicity1.65, crystallization time of24h, crystallization temperature of140℃.Molecular sieve singly adsorbed phosphate radical is not very good. Loadinglanthanum oxide on the molecular sieve adsorption quantity will increase. Al48-M41is the best carrier to adsorb phosphorus. There are pore structure and aluminumcontent two reasons for influence of adsorption. At the condition of low aluminumcontent pore structure is the main factors effecting phosphorus adsorption. Along withthe increase of the aluminium content of carrier, the aluminium content became themain factor influencing adsorption amount. Lanthanum oxide is the main activecomponent.Different phosphorus content impregnated Al48-M41, the adsorption capacity is56.13mg/g at15%. The phosphorus removal rate is89.80%; Firstly, the phosphorusadsorption of La15-Al48-M41linearly increases with adsorption time, then increaseslowly. Finally the phosphorus adsorption tends to saturation and the adsorptionquantity is60.43mg/g; When dosing quantity is0.12g, phosphorus removal rate is96.01%,which is the best dosing quantity; The adsorption quantity highest60.29mg/gat PH=4. The pH change at different initial pH, indicating that the electrostatic force and ion exchange between lanthanum oxide and phosphate radical is the main reasonfor the phosphate radical. Adsorption kinetics and thermodynamic are studied. It isconcluded that the secondary dynamics model is better fitted experimental data thanthe first dynamics model; Thermodynamic adsorption data can be better fittingLangmuir model indicating adsorption is a chemical adsorption. Reproducibility testresults that adsorbent of phosphorus reaches as high as90%. Reproducibility is verygood. Amino modified different carrier to test phosphorus adsorption capacity.N-Al48-M41with the highest phosphorus adsorption12.31mg/g is obvious on thelow side comparing with lanthanum modified carriers.