| SO42-(Sulfate radical), a common anion in inorganic chemical industry, can result in a bad impact on the production of several basic chemical materials,SO42- must be removed in the basic chemical industry of salt making, chlor-alkali and soda ash. Among the methods of SO42- removing, sorption-desorption is an efficient one. The method of sorption-desorption, which with the sorbent based on zirconium, is expected to replace the traditional methods of SO42- removing, thereby the technologic upgrade of the basic chemical industry is realized.Using ZrOCl2·2H2O,γ–Al2O3 and ammonia as materials, ZrO(OH)2-coatedγ–Al2O3 was prepared with the method of precipitation. By employing the test methods of IR, TEM, Zeta potential, etc, the technology of preparation was investigated. The experimental results indicate that, azeotropic distillation drying is an economic and efficient way, concentration of ZrOCl2·2H2O should be less than 0.6mol/L, and appropriate ratio of zirconium to aluminium is about 4.Using the method of macerating, ZrOCl2 loading on D418 was produced. Influence including time of macerating, pH, and temperature on the amount of load was studied. The proper conditions show that, room temperature is appropriate, the suitable pH is equal to 5, and time of macerating is 16 hours.Using the gravimetric method, property of SO42- sorption on the two products was studied. Factors including temperature, pH, concentration of SO42- and Cl- have impact on the result of SO42- removing. Desorption result of ZrO(OH)2-coatedγ–Al2O3 with NaOH was investigated. The results showed that ZrO(OH)2-coatedγ–Al2O3 has the higher percentage of sorption. The percentage of adsorption will decrease with the increase of SO42- concentration, and the amount of sorption is unchanged. The room temperature is proper, the suitable pH is equal to 3.The addition of Cl- will increase the percentage of sorption, and NaOH with the concentration of 25g/L is a good choice for the regeneration of sorbent.
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