Study On Adsorption Treatment Of Cu(?) By Rice Straw-derived Biochar From Wastewater

In this experiment,300?,500?,700? biochars and dissolved organic matter produced by different decay stages of straw(hereinafter referred to as DOM)are made from farmland abandoned rice straw as raw material.After Investigating the surface properties of biochars by SEM,BET,FTIR and elemental analysis,we have come to some conclusions: SEM results show that there is a large number of channels and pores in the biochars prepared at 700?;BET results show that 700°C charcoal has the best specific surface results;FTIR results show that biochars contains multiple oxygen-containing functional groups such as-OH,-COOH,etc.The results of elemental analysis show that as the pyrolysis temperature increases,the content of C increases,and the content of O and H decreases as the pyrolysis temperature increases.There is no obvious rule for the content of N,and the number of atoms is H/C?O/C and(O+N)/C decrease as the pyrolysis temperature increases.This experiment also explored the effects of environmental conditions of pH,concomitant ions,adsorption time,and DOM on the adsorption of Cu(II)by biochars.In particular,we compare the different of biochars(before and after DOM preloading),and explore themechanism by three-dimensional fluorescence,FTIR and other techniques.The results of the experiment showed that the adsorption capacity of biochar at 700°C was the strongest,and that of 21 dDOM was the best.When the Cu(II)is low,the biochars preferentially adsorbs DOM,and the preloaded DOM is favorable for the adsorption of Cu(II).When the Cu(II)is high,the DOM and Cu(II)will be complexed.The application results in copper-containing electroplating wastewater show that: biochars combined with 21 dDOM to remove copper has a good effect,and the removal rate reaches 99.16%.This experiment finally found the best conditions for the removal of Cu(II)adsorption,and provided theoretical basis and technical support for the use of biochars adsorption treatment of copper-containing wastewater.