The Functionalization Of Natural Wood And Its Application In Water Treatment

With the rapid development of the world economy,the construction of ecological civilization is extremely important.In the construction of ecological civilization,solving water pollution is an important link.Therefore,to control water pollution and obtain safe drinking water is an important problem to be solved urgently.Based on the above existing problems,the contents of this paper are summarized as follows:?1?Natural wood has three-dimensional pore structure,and its chemical composition is mainly composed of cellulose,hemicellulose and lignin.We modified mercapto functional groups on wood cellulose by organic reaction to prepare SH-wood membrane.The natural three-dimensional and irregular pore structure of wood is conducive to improving the water flux and increasing the contact opportunities between heavy metal ions and sulfhydryl groups on the channels.In addition,the water treatment performance of SH-wood membrane is further improved through the three-layer superposition design.The results showed that the three-layer SH-wood filter could efficiently and rapidly remove Cu²⁺,Pb²⁺,Cd²⁺,Hg²⁺from the wastewater.When the treatment rate was 1.3×10³ L·h^-1·m^-2,the removal rate remained above 96%,and the concentration of heavy metal ions after this process could reach the drinking water standard.At the same time,after the material was reused for 8times,the water treatment performance did not decrease significantly.Therefore,SH-wood membrane have the advantages of high efficiency,strong regeneration ability,good scalability and low cost in the field of heavy metal wastewater treatment.?2?Carbonized wood can not only maintain the three-dimensional pore structure of natural wood,but also has a good electrical conductivity and a wide range of applications in the field of electrochemical materials.Wood contains a large number of nanofibrils,which have tip effects under the action of electric field after carbonization.Three-dimensional carbonized wood membrane?3D WCM?was prepared by calcining at a simple high temperature,and external voltage was applied to electrochemical sterilization in drinking water.The three-dimensional pore structure of wood after carbonization is not only conducive to high-flux water treatment,but also not easy to cause bioflotting.Moreover,when the treatment efficiency was 3.8×10³ L·h^-1·m^-2,low voltage?10 V?was applied to realize the high bactericidal performance?99.999%?,and the bactericidal performance did not decrease significantly after long-term use?>12 h?.Carbonized wood membrane has the advantages of high efficiency,fast preparation,green and sustainable in the field of drinking water sterilization.?3?On the basis of the tips structure of nanofibrils in carbonized wood membrane,in order to achieve efficient sterilization at lower voltage,we introduced silver nanoparticles?Ag NPs?with antibacterial effect.The carbonized wood membrane loaded with silver nanoparticles?3D Ag NPs/WCM?was prepared by immersion and high-temperature carbonization in silver nitrate solution,and then applied with voltages to electrochemical sterilization of drinking water.The tips structure of nanofibrils in wood produces a high electric field that induces bacterial electroporation.In addition,Ag NPs are evenly distributed in the channel of carbonized wood.When the water containing microorganisms passes through,Ag NPs is more likely to invade the microorganisms with damaged membrane,thus promoting the inactivation of microorganisms.Benefiting from the synergistic effect of the strong electric field generated by the nanofibrils of 3D Ag NPs/WCM and the antimicrobial activity of Ag NPs,when the treatment efficiency is 3.8×10³ L·h^-1·m^-2,the bactericidal performance of 3D Ag NPs/WCM filter against four common bacteria?E.coli,Salmonella,Enterococcus faecalis and Bacillus subtiliflora?exceeds 5 logs?99.999%?at a voltage of 4 V.3D Ag NPs/WCM composite has the advantages of high efficiency,low energy consumption,fast,green and sustainable in the field of drinking water sterilization,and is suitable for large-scale use and single use.