Preparation Of Cellulose Xanthate Loaded With Titanium Sol And Its Adsorption Properties For Ni²⁺?Cu²⁺ And Co²⁺

In this paper,microcrystalline cellulose was used as a raw material for modification,and titanium sol was loaded to synthesize titanium sol/cellulose xanthate adsorbent?TCX?.The adsorption performance of the adsorbent to Ni,Cu and Co metal ions was investigated,and the adsorption process mechanism was obtained by preforming adsorption experiments and desorption experiments.The results of this paper would provide a scientific basis for practical applications.The main research contents are as follows:?1?Using microcrystalline cellulose as the raw material and CS₂ as the modifier,cellulose xanthate is synthesized under the presence of NaOH.The titanium sol is prepared by the sol-gel method and supported on the cellulose xanthate to obtain the adsorbent TCX,scanning electron microscopy,and energy spectrum analysis were used to characterize the synthesized product.The analysis results showed that xanthanic acid groups and titanium sol were introduced into the cellulose molecule,and the product surface was rough.?2?The adsorption experiments of Ni²⁺solution,Cu²⁺solution and Co²⁺solution were carried out using TCX as adsorbent,and four influence factors,reaction time,temperature,the amount of adsorbent and pH,were discussed for the rate and the amount of adsorption for the three ions.When the adsorption time is 90 min,the adsorption temperature is 40?,the amount of adsorbent added is 0.30 g,and the pH value of solution is 5,the adsorption rate for Ni²⁺is 94.92%,and the adsorption capacity is 3.95 mg/g;when the adsorption time is 90 min,the adsorption temperature is 40?,the amount of adsorbent added is 0.10 g,and the pH value of solution is 5,the adsorption rate for Cu²⁺is 95%,and the adsorption capacity is11.87 mg/g;when the adsorption time is 60 min,the adsorption temperature is 45%When the pH value of solution is 4,the adsorption rate for Co²⁺is 95.28%,and the adsorption capacity is 5.95 mg/g.The Langmuir isotherm adsorption model was used to fit the adsorption isotherms.The coefficient R² are greater than 0.99,and the correlation coefficient is good;the Gibbs free energy changes??G?during the adsorption of Ni²⁺,Cu²⁺,and Co²⁺are-5.45kJ/mol,-4.79 kJ/mol,and-3.95 kJ/mol,respectively.The?G results showed the absorption process can spontaneously carried out.the saturated adsorption amounts were 61.91 mg/g,62.01 mg/g,67.06 mg/g respectively;by studying the adsorption kinetics,the adsorption process of the adsorbent for Ni²⁺,Cu²⁺and Co²⁺conformed to the quasi-second-order kinetic model,and the correlation coefficients R² are greater than 0.99.The adsorption process is controlled by the chemical surface adsorption process.?3?Under the optimal adsorption conditions,the selective adsorption experiment of Ni²⁺,Cu²⁺and Co²⁺mixed solution using TCX as an adsorbent showed that the titanium sol-loaded cellulose xanthate adsorbed Cu²⁺is best,followed by Co²⁺and Ni²⁺.Desorption experiments show that HNO₃ can desorb and recover Ni²⁺,Cu²⁺and Co²⁺on the adsorbent.The desorption rate for Ni²⁺,Cu²⁺and Co²⁺was 91.36%,92.66%,and 82.71%respectively.After three desorption adsorption desorption,the adsorbent still has good adsorption performance and achieves the effect of adsorbent reuse.The research results in this paper showed that the titanium sol-loaded cellulose xanthate is a recyclable,and efficient adsorption material,which can effectively treat wastewater that contain Ni,Cu,and Co heavy metal ions,and recover the metal in water.