Preparation Of Urea-formaldehyde Biomimetic Materials And Their Adsorption Properties For UO₂²⁺ And Pb²⁺

The harm caused by the pollution of uranium and lead in the environment to humans has always been the focus of attention.Because both uranium and lead have strong bioaccumulation effects,they combine with kidney protein tissue after entering the human body and cause long-term harm to the human body.In order to study the combination of uranium or lead with kidney protein tissue and reduce the long-term harm to human body,this paper used urea-formaldehyde resin as matrix and added kidney hydrolysate to prepare a urea-formaldehyde biomimetic material simulating human kidney protein tissue.By investigating the adsorption and desorption behavior of materials on uranium and lead,it provides effective protection measures to reduce the harm of uranium and lead.Through the auxiliary study of amino acid-modified urea-formaldehyde-based materials,it was determined that 375 mL of pig kidney hydrolyzate was added to prepare urea-formaldehyde-based biomimetic materials.Then,combined with the activated carbon tube production process,the urea-formaldehyde-based biomimetic material was made into a tubular material,and was used together with a circulating reaction device to dynamically simulate the process of body fluid flowing through the kidney tissue,thereby achieving the effect of a cyclic reaction.The morphological,functional group structure and elemental composition of urea-formaldehyde biomimetic materials were characterized by SEM,FT-IR and XPS.The results showed that the structure of biomimetic materials was stable.Additionally,it contains groups such as-NH₂ and-NHCO-that can be combined with UO₂²⁺and Pb²⁺.The adsorption experiments showed that the adsorption reaction was carried out at a temperature of 37? and pH=7.0.After 4 h,the adsorption reaction reached equilibrium.The equilibrium adsorption capacities of the materials for uranium and lead were 28.62mg/g and 30.54 mg/g,respectively.The adsorption of uranium or lead by biomimetic materials is well fitted by pseudo-second-order model.The results of tea desorption experiment showed that green tea and white tea had the best desorption effect on uranium and lead,followed by oolong tea and yellow tea,black tea and red tea had the worst desorption effect.As the ratio of tea to water increased,desorption of uranium and lead continued to increase.Therefore,tea can be considered as a desorbent for uranium and lead in kidney protein tissue.Although tea desorption effect and desorption rate are not as good as related drugs,but it has no side effects on human body and can be safe and long-term drinking.