Study On Phosphorus Removal By Chelating Adsorbents

Phosphorus and phosphorus compounds are indispensable in life activities.However,Excessive levels of phosphorus in water can cause eutrophication of the water and cause algal bloom,while the presence of phospholipids in oil will reduce the quality of the oil and affect the subsequent oil refining.In this paper,chelating resin was used as an adsorbent to study the removal of phosphorus from water phase and oil.First of all,an improvement was made to the problems existing in determining the phospholipid content in oil by the national standard method.The process of carbonization and ashing of liquid oil in the national standard method is transformed into the carbonization and ashing process of solid soap,which improves the precision and accuracy of the method.In phosphorus removal study in water-phase,firstly,the IRC747,IRC748 and S957 chelating resins with La³⁺and Al³⁺immobilized were used to purify the simulated phosphorus-containing waste water?containing 20 mg/L phosphorus?for the removal of phosphorus in water phase,and the La form IRC747 resin with the best phosphorus removal effect was selected,and its adsorption effects under different conditions were further studied.The results show that the higher the pH of the solution used for resin transformation,the greater the bonding capacity of metal on the resin and the effect of phosphorus removal in the aqueous phase.And the lower the pH?in the range of 3 to8?of the phosphorus-containing aqueous solution,the higher the phosphorus adsorption amount,but the adsorption amount reduces obviously when the pH is less than 3;moreover,the presence of Cl^-,SO₄^2-and NO₃^-in the solution enhances the adsorption effect of phosphorus on the resin,and the presence of HCO₃^-inhibits the adsorption effect of phosphorus on the resin.At the same time,the infrared characterization before and after the resin adsorption shows that the phosphate is adsorbed on the resin.Then,the kinetics and thermodynamics of La form IRC747 resin for phosphorus removal in aqueous phase were studied.The following conclusions are reached:the phosphorus adsorption in aqueous phase by resin reaches equilibrium at 8 h,and the pseudo-second-order model can describe this adsorption process well;at the same time,the higher the temperature,the greater the adsorption capacity of the resin;by trying different kinds of models to fit,it is concluded that the Langmuir model can fit the experimental data of IRC747 La resin at different temperatures very well;by calculating the thermodynamic parameters,we can conclude that phosphorus adsorption in aqueous phase by IRC747 La resin is an endothermic,spontaneous,entropy increasing process.For the oil degumming,the existing oil degumming methods were first used as control experiments;then the two kinds of crude oil were degummed by IRC747,IRC748 and S957-water degumming.The results show that,on the one hand,the resin has a certain degree of effect on the oil degumming,but compared with the traditional oil degumming methods,its effect is not ideal.On the other hand,the resin has a certain removal effect on metal ions,free fatty acids,and moisture for oil.What's more,its effect is obvious and has certain advantages.