Studt On The Removal Of Heavy Metal Ions From Wastewater Bya New Type Of Heavy Metal Trapping Agent

As an extension of traditional physics,chemistry and biotechnology to remove heavy metal ions,heavy metal traps can strongly complex with heavy metal ions to form stable macromolecular ligands and realize heavy metal removal.It has simple operation,good treatment effects,short action time and economic cost.Low advantages,but in the process of removing composite or multiple heavy metal ions,there are more or less problems such as large ion interference and removal differences.In this paper,a new type of metal trapping agent（DTC_S）is prepared by graft polymerization,and the competitive removal of multiple heavy metal ions and mechanism research are carried out,and it is applied to the treatment of heavy metals in electroplating wastewater,in order to realize the application and promotion of wastewater treatment under working conditions.In order to obtain a high-performance heavy metal trapping agent composition,a comparative study of the active agent SDBS,active group donor CS₂,and cross-linking agent NaOH on the removal of heavy metal ions by the heavy metal trapping agent,by investigating acid-base tolerance,temperature stability and active groups and other performance indicators,further revealing the strengthening effect of sodium dodecylbenzene sulfonate and CS₂ on the removal of heavy metal ions by the heavy metal trapping agent.In order to achieve the removal of heavy metal ions in wastewater under complex conditions by heavy metal traps,the removal of Cu²⁺,Cd²⁺,and Ni²⁺was used as a probe to compare simulated Cu²⁺,Cd²⁺,Ni²⁺single-source wastewater and electroplating wastewater,and explore the pH value,the reaction temperature,the amount of trapping agent,and the reaction time affect the performance of heavy metal traps in removing complex heavy metal ions,and the relevance of heavy metal traps competing to remove multiple metal ions is analyzed.In order to further reveal the mechanism of the new heavy metal trapping agent for removing heavy metal ions from wastewater,classical kinetics is used to reveal the kinetic characteristics of the new heavy metal trapping agent to remove heavy metal ions,and the thermodynamic model is used to reveal the energy conversion law of the new heavy metal trapping agent to remove heavy metal ions,and establish a diffusion model to reveal the internal process of the new heavy metal trapping agent to remove heavy metal ions.The results show:（1）Predominant composition of the new heavy metal trapping agent prepared:when sodium dodecylbenzene sulfonate is 1.66mmol,CS₂ is 0.82mmol,and NaOH is1.64mmol,Cu²⁺with an initial mass concentration of 200mg/L is removed.The amount is 164.34mg/g,and the removal rate is 70.29%;SDBS and NaOH have a binary linear relationship,and the interaction between the two has the most significant impact on the performance of the new heavy metal trap.（2）The prepared new heavy metal trapping agent has obvious characteristic peaks at 1640cm^-1 and 3433cm^-1,which are the characteristic functional groups of C-S and-O-H respectively;its solid has the characteristics of surface-associated flower crown morphology;It has good acid-base resistance in the range of 3～12,temperature stability in the range of 25～65℃,the detection amount of·OH in the system is 0.43mg/L,and it has good performance in removing heavy metal ions from wastewater.（3）The new heavy metal trapping agent removes Cu²⁺,Cd²⁺,Ni²⁺single-source simulated wastewater with an initial mass concentration of 500mg/L.It is found that the removal amount of Cd²⁺is 319.79mg/g,the removal rate is 72.13%,and the removal amount of Cu²⁺is 241.01mg/g.The removal rate is 60.28%,the removal amount of Ni²⁺is 141.42 mg/g,and the removal rate is 34.48%.Electroplating wastewater application research shows that Cu²⁺removal is 385.34mg/g,removal rate is 99.93%,Cd²⁺removal is 79.34mg/g,removal rate is 27.35%,Ni²⁺removal is 140.38mg/g,removal rate is 21.78%,the removal of Cu²⁺is not affected by the competition of heavy metal ions,showing stable performance advantages,the removal of Cd²⁺and Ni²⁺is greatly affected by the competitive complexation of multiple ions;After treatment,the ammonia nitrogen removal rate of electroplating wastewater can reach 100%.（4）The process of removing Ni²⁺,Cu²⁺and Cd²⁺is more in line with the quasi-second-order kinetic model.The diffusion rate（k₂）is Ni²⁺（0.0117）>Cd²⁺（0.0016）>Cu²⁺（0.0010）;the order of△H from thermodynamic analysis is△H_Ni²⁺（95.16）>△H_Cd²⁺（11.16）>△H_Cu²⁺（7.41）>0,indicating that Ni²⁺,Cu²⁺,Cd²⁺removal processes are all endothermic reactions;△S_Ni²⁺（0.33）>△S_Cd²⁺（0.04）>△S_Cu²⁺（0.02）,indicating a new type the active group of the heavy metal trapping agent complexes with heavy metal ions to form a ligand,and the stability is Cu²⁺>Cd²⁺>Ni²⁺.（5）The removal of Ni²⁺,Cu²⁺and Cd²⁺by the new heavy metal trapping agent is mainly divided into external diffusion process and internal diffusion process.The diffusion rate k_f of the external diffusion process is Cd²⁺（0.0274）>Cu²⁺（0.0233）>Ni²⁺（0.0204）,indicating that the driving force of external diffusion is Cd²⁺>Cu²⁺>Ni²⁺.The internal diffusion process includes three stages:internal membrane diffusion process,internal diffusion process and diffusion equilibrium process.The internal diffusion process is the core process of removing heavy metal ions.The internal diffusion rate constant k_i is Cu²⁺（6.56）>Cd²⁺（4.54）>Ni²⁺（0.51）indicates that the affinity relationship between the new heavy metal trapping agent and heavy metal ions is Cu²⁺>Cd²⁺>Ni²⁺.