Study On The Influencing Factors Of Electricity Production Performance Of Aluminum-Air Battery And The Performance Of Humic Acid Removal

A series of metal-air batteries represented by aluminum-air batteries require only the participation of metals and oxygen in the air to generate electricity.These batteries have the advantages of high energy density,simple reaction equipment,and no pollution to the environment by reaction products.,It is a kind of green energy with great development potential.The current research on metal-air batteries is mainly focused on the optimization of power generation performance,but according to the reaction principle（taking aluminum-air batteries as an example）,the battery will produce aluminum salts during the reaction process.The aluminum salt is a good medicament for the coagulation process.Therefore,coagulation and other processes using battery devices are practical in principle,and the battery can remove pollutants in the water while generating electricity.This approach is in line with the concept of green and sustainable.However,there are relatively few studies on applying metal-air battery devices to water treatment,and only a few people have used metal-air batteries to conduct research on arsenic,algae and phosphorus removal.Large-scale exploration and research has not yet been carried out.The experiment is based on an aluminum-air battery reaction device,by monitoring the battery’s real-time current/voltage,measuring the polarization curve and battery internal resistance.The effects of factors such as electrical conductivity,plate spacing,and pH on battery performance were investigated;The experiment measures the total concentration of aluminum produced,comparing the gap between the theoretical calculated value and the actual value measured by ICP-MS.From the perspective of the coagulation process,the aluminum morphology is classified by Al_a,Al_b,and Al_c.The Al-Ferron complex colorimetry was used to determine the morphology of aluminum produced by aluminum-air batteries under different conditions,and to find an effective method to control the morphology of aluminum produced by batteries.Finally,the aluminum-air battery was used to treat the humic acid in the water.By setting different physical and chemical conditions,such as different pH values,different electrical conductivity,and different pollution loads,to explore the influencing factors of humic acid removal using aluminum-air batteries.In the experiment,the determination of humic acid was determined by the measurement of UV₂₅₄and the scanning of three dimensional excitation-emission fluorescence spectra in samples.At the same time,flocculation monitoring instrument was used to monitor the morphology of floc produced in the reaction process in real time.The main conclusions of the experiment are as follows:1.The increase in the NaCl concentration of the electrolyte will enhance the power generation performance of the aluminum-air battery.The power generation performance is the best when the NaCl concentration is 3.5 g/L,and the output voltage can reach 342mV.Weak,power density up to 427.6 mW/cm2;The increase of the battery plate spacing will increase the internal resistance of the battery,which will affect the battery’s power generation performance.When the plate spacing is 3cm,the battery internal resistance is only 12Ω,and the output voltage can reach about 300mV,while the plate spacing increases to 12cm.,The internal resistance of the battery is increased to 32Ω,and the output voltage is correspondingly reduced to about 190mV;The pH value is also a factor that affects the power generation performance of the battery.The pH value is in the range of 5-9.The power generation performance at pH values 5 and 9 is better than that under other conditions.The power generation performance is the best,the output voltage can reach 247mV,the power density is 326.1mW/cm2,and the pH value of the worst power generation performance is 7,the output voltage is about 227mV,the power density is only about 250mW/cm2 The reason for this phenomenon is that the passivation layer on the surface of the aluminum electrode dissolves under the condition of strong acid and alkali,weakening the polarization phenomenon of the aluminum electrode;Under the same other conditions,the hydraulic cycle condition has little effect on the battery’s power generation performance.The output voltage difference between the best power generation condition and the worst power generation condition is less than 5mV;while using different external resistances,the battery’s The power generation performance is also different.It is most suitable to connect a 20Ωresistor to the battery.A small 10Ωresistor will cause the output voltage of the battery to drop in the later stage of the reaction.When a large resistance of 50Ωis used,the battery’s power generation performance is poor.2.The concentration of aluminum produced by the battery reaction is positively correlated with the power generation performance of the battery.This is because the power generation performance is related to the amount of electron transfer.The better the power generation performance,the more electron transfer.For example,when the NaCl concentration of the electrolyte is 3.5g/L,the pH value is 9 and the actual measured aluminum concentration is 8.85 mg/L,17.49 mg/L and 26.04 mg/L,respectively.The calculated aluminum concentrations are 8.67 mg/L,17.25 mg/L and 25.78mg/L,and the comparison shows that the difference between the two is small.The theoretical calculation method can be used to roughly estimate the aluminum concentration produced by the aluminum-air battery;The NaCl concentration of the electrolyte has a significant effect on the total aluminum concentration produced by the battery.When the NaCl concentration is3.5 g/L,the total aluminum concentration produced is about 25 mg/L after 180 min of the reaction.The increase in aluminum concentration causes the proportion of Al_b in water to increase,from 18%to 32%at 0.5g/L;Different pH values have little effect on the total aluminum concentration,but have a greater impact on aluminum morphology.The proportion of Alb produced when the pH value is 5-7 is about 30%,while the alkaline content decreases to 20%Most of them exist in the form of Alc.On the whole,the aluminum forms under various conditions are distributed in the form of Al_c>Al_b>Al_a.3.The method of coagulation of aluminum-air battery device to remove humic acid in water is feasible and effective.When the concentration of NaCl is 1g/L,it has a high removal efficiency for humic acid water samples with a concentration of 20mg/L and below.When the UV₂₅₄ value of the 10mg/L humic acid water sample was reduced from 0.3 to about0.03,the removal rate was close to 90%,and the UV₂₅₄ of the 20mg/L humic acid water sample was reduced from 0.7 to about 0.1;The NaCl concentration of the electrolyte,the concentration of humic acid and the pH of the solution all have a certain effect on the coagulation process.The increase in NaCl concentration can speed up the process of coagulation to remove humic acid,and the increase in humic acid concentration can make the reaction has a higher degree of coagulation.PH not only affects the existence form of some functional groups of humic acid,but also has a certain influence on the form of aluminum produced in the reaction.Overall,in the range of pH value 5-9,the coagulation degree and flocculation of flocs under acidic conditions.The removal effect of humic acid is better than that under alkaline conditions.When the reaction is carried out to 60min,only the value of UV₂₅₄ at pH 5 is less than 0.1.At the same time,this method is compared with the conventional coagulation method,and it is found that the addition of the conventional coagulation agent polyaluminum chloride has a poor effect on the removal of humic acid by coagulation.The value of UV₂₅₄ is still around 0.3.The experiment explored the factors that affect the power generation performance of aluminum-air batteries,and determined the form of aluminum produced by the reaction,which provided a theoretical basis for future related research.At the same time,the battery device was applied to the coagulation treatment and the use The feasibility of coagulation of aluminum-air battery device to remove humic acid in water provides new ideas for the application of aluminum-air battery coagulation technology in the field of water treatment Figure[43]Table[4]Reference[89]...