Study On Lithium Adsorption Material For Oil Field Brine Extraction

With the rapid development of battery and photoelectric industries,the demand for lithium is growing.Oilfield brines contain abundant lithium resources,but also contain a lot of calcium,magnesium,potassium,sodium plasma,preparation of high adsorption capacity,high selectivity adsorption materials for lithium extraction oilfield brines has become an important subject.In this thesis,the research of lithium adsorption materials extracted from oilfield brine mainly includes the following work.（1）The adsorption performance of lithium ion exchange resin SQ-06L have been evaluated:the adsorption capacity was 3.18-4.00 mg/g at the concentration of lithium ion 50.00-200.00 mg/L;The desorption and cycling properties of the resin SQ-06L have been investigated.The desorption rate of lithium was lower than 50%.（2）In order to prepare the ion sieve with high adsorption capacity,manganese ion sieve was prepared by ball milling modification and high temperature solid phase calcination.The influences of molar ratio of raw material,calcination temperature and calcination time on lithium ion adsorption under preparation conditions were explored.The equilibrium adsorption capacity of HMO-0.5-900-8 under optimal conditions was23.25-27.06 mg/g when the concentration of lithium ion was 50.00-200.00mg/L.Through XRD,XPS,SEM and BET characterization,it was found that HMO-0.5-900-8 was a pure phase Li Mn₂O₄with a cube shape and a large pore size and specific surface area.It has high selectivity to lithium ion in sodium,potassium and lithium polymetallic ion solution.The adsorption kinetics model was quasi-second-order fitting,and the isothermal adsorption model was Langmuir adsorption.The higher p H value was,the larger equilibrium adsorption capacity was.When the concentration of hydrochloric acid was 0.30-1.20mol/L,the desorption rate of Li was 94.70%-98.40%and the dissolution loss rate of Mn was 14.30%-17.50%.After 5 cycles,the equilibrium adsorption capacity decreased by 16.60%.In order to solve the problem of high manganese dissolution loss rate,magnesium chloride and iron oxide were doped for modification.The influences of doping molar ratio,calcination temperature and calcination time on lithium ion adsorption under the preparation conditions were explored,and the ion sieve LMO-Mg-1 and LMO-Fe-1 under optimal preparation conditions were obtained.The equilibrium adsorption capacities were 22.75-27.36 mg/g and 24.37-28.26mg/g when the concentration of lithium ions was 50.00-200.00 mg/L,respectively.It was found that the target ion screen was synthesized successfully and the morphology and structure did not change obviously.The dissolution loss rates of LMO-Mg-1 and LMO-Fe-1 were 10.60%-11.98%and8.99%-11.06%,respectively,and the dissolution loss rates of manganese were reduced.The adsorption properties and p H effect were basically consistent with that of HMO-0.5-900-8,and the selectivity was higher than that of HMO-0.5-900-8.（3）In order to prepare ionic sieve with low dissolution loss ratio,the aluminum-based inorganic lithium extraction adsorbent was prepared by using aqueous solution coprecipitation-high-temperature calcination method.The influences of molar ratio of raw material and calcination temperature on lithium ion adsorption under preparation conditions were explored,and the aluminum-based adsorbent Al-1-800-2 under optimal preparation conditions was obtained.The equilibrium adsorption capacity was 4.70 mg/g when the concentration of lithium ion was 100.00 mg/L.The structure and specific surface area of Al-1-800-2 were determined by XRD and BET characterization.Al-1-800-2 has high selectivity to lithium ion in sodium,potassium and lithium polymetallic ion solution.The desorption performance of Al-1-800-2 have been investigated.The desorption rate of lithium in 0.01 mol/L hydrochloric acid was 62.34%,the dissolution loss rate of aluminum was 5.25%,and the lithium desorption rate of lithium in deionized water was 16.13%.No dissolution loss of aluminum was found.（4）In order to prepare granular adsorbent with high adsorption capacity and low dissolution loss rate,LMO-Fe-1 was formed and granulated,and the influence of ion sieve prepared with different precursor addition amounts on lithium ion adsorption was explored,and PAA-LIS-4 particle adsorbent under optimal preparation conditions was obtained.When the concentration of lithium ion was 50.00-200.00 mg/L,the adsorption capacity was 5.93-6.97mg/g.Through XRD and SEM characterization,it was found that PAA-LIS-4was a porous sphere covering the precursor.The adsorption properties,selectivity and influence factors of p H value of PAA-LIS-4 were similar to those of LMO-Fe-1.The desorption and cycling properties of PAA-LIS-4 were investigated.When the concentration of hydrochloric acid was 0.6 mol/L,the desorption rate of lithium was 70.69%,and the dissolution loss rate of manganese was 1.41%.It was found that the adsorption capacity was reduced by 8.70%after 5 cycles,and the dissolution loss was relatively low.