Study On Resistant Potassium Ion Permeation Composites

Modified emulsified asphalt is a good impervious materia due to its structural characteristics.Compared with ordinary asphalt,it has good liquidity and cracking resistance,it can also be used for micro-table seal,which will effectively reduce the cracking and loosening of the floor to reduce infiltration hazards.However,the structure and preparation conditions of the materials have significant relation with their properties.Therefore,on the one hand,the modification of the material's structure can effectively improve its application value,on the other hand,a variety of materials are combined to change the distribution of internal structure and improve its performance.In this paper,different contents of potassium-containing carrier materials were prepared by soaking method,and then SBS modified emulsified asphalt was prepared under different technological conditions,and then the potassium-ion permeation composites were prepared by high speed shearing method,and the anti-potassium ion permeability under different circumstances was studied.The main results of this paper are as follows:1.SPR is chosen as carrier of potassium containing materials,due to its certain hygroscopic property and good ion exchange function.Such materials were found good load capacity in the load test,which is over hundreds times of its quality.So it can be used as barrier to slow down the loss of potassium ions and as load materials.It is found through experiments that kl-5a is relative better than other materials,the load level reach 85%at the conditions of 40?,pH 7,60 min,0.1g:100mL?kl-5aSPR:the volume of solution?,and at the concentration of 0.020mol/L.The potassium ions in solution is retained to a large extend,which indicates that it can be considered as protective materials for reducing potassium fertilizer loss.2.The linear fitting of the Langmuir and Freundlich adsorption isothermal equations of the experimental data shows that,the Langmuir adsorption isothermal equation can well reflect the exchange process of the kl-5a resin to the potassium ion.Through calculation of the correlation parameters of thermodynamic function,it is shown that the temperature is favorable to the adsorption process of potassium ions by kl-5a resin.The kinetic equation fitting of experimental data points shows:it is physical adsorption if?h<40 kJ/mol,and the main speed control step is in-particle control.The apparent activation energy is Ea=6.033kJ/mol.3.Through the experiment,it is found that when the shear temperature reaches 170,the shear rate reaches 3000rpm,the shearing time reaches 1 hour,and then the development of 1 hour at 160?,the modified asphalt can be prepared well.By single control of emulsified asphalt conditions,and under the condition of characterization,it is confirmed that the SBS content is 2³%,pH value is 5⁶,emulsified water temperature is80?and the oil temperature is 120?,emulsifier content is 1%,the ratio of oil:water is60:40,and composite stabilizer?PVA:CaCl₂=1:1?content is 0.15%.4.After a systematic consideration,it has certain reference value that the modifieer SBS content is 3%,the additive load materials content is 6%,and the composite still shows good resistance to potassium ion permeation.Under standard conditions,with the increase of time,the total amount of potassium ion permeation flux is increasing,but the composites added with modifiers and fillers is obviously effective in slowing down the loss of potassium ions,and the its growth rate gradually slows down.Under the condition of simulating Salt Lake water pressure,with the increase of time,the potassium ion permeation flux of composite material increases,the trend of potassium ion permeation flux is fast first,and then slow down.The time of the penetration flux is shortened relative to the standard condition,and the effect of external pressure has caused the permeation of potassium ions,but the composites still have a certain effect on the loss of potassium ions.In the simulated Salt Lake brine conditions,with the increase of time,the potassium ion permeation flux of composites increases,and because of the saline-alkali corrosion,which is a long-term process,the potassium ion permeation flux is larger than before,the addition of modifiers and fillers can reduce the loss of potassium ions in certain period.