Preparation Of Lignin Xanthate Resin Loaded On Bentonite And Its Adsorption Performance Research

Based on the lignin of industry waste water as raw material,we prepared the lignin xanthate resin which has porous structure and better adsorption effect. We used bentonite reacted with lignin xanthate resin and prepared the lignin xanthate resin loaded on bentonite compound biological adsorption materials (refered as modified bentonite).We used the compound biological adsorption materials made as globule (refered as compound sphere), in order to improve the recovery rate. We further studied the adsorption mechanism of modified bentonite and compound sphere toward heavy metal and antibiotic. The main content of the research and the results are as follows:(1) Lignin xanthate resin (LXR) which has porous structure was synthesized by a two-step reaction (hydroxyl methylation reaction and xanthate acidification) from alkaline lignin and carbon disulfide. We studied the adsorption effect of LXR toward Pb2+,the experimental results of LXR adsorb Pb2+ showed that: dealed with 25 mg/L Pb2+ solution, the best adsorbent dosage was 0.04g/50ml, and at this point the lead removal rate can reach 93.5%; the adsorption kinetics of LXR followed the first order kinetics model; the adsorption isotherm followed Langmuir adsorption model, which shows that the adsorption of LXR toward Pb2+ was adsorption monolayer adsorption.(2) The lignin xanthate resin was reacted with bentonite, we got the compound biological adsorption materials,the characterization was also studied, the best ratio of bentonite and lignin xanthate resin was 10:1.5. We examined the adsorption properties of compound biological adsorption materials toward Hg2+ and doxycycline hydrochloride, the experimental results showed that the saturated adsorption amount of Hg2+and doxycycline hydrochloride were 35.7143mg/g and 454.54mg/g, the adsorption kinetics equation followed the pseudo-second order kinetic equation; the adsorption isotherm of Hg2+and antibiotics followed the Langmuir model, showed that its adsorption of Hg2+and antibiotics were monolayer adsorption; dealed with Hg2+solution of 20mg/L, the best adsorbent dosage was 0.6g/50 ml, the Hg2+removal rate can reach above 95.17%;dealed with 30 mg/L of doxycycline hydrochloride solution, the best adsorbent dosage was 0.1g/50ml, the removal rate of doxycycline hydrochloride can reach above 93.57%.(3) Due to the state of powder lignin xanthate resin loaded on bentonite, was difficult to recycle after the adsorption and separated from the water. In this paper,we used the sodium alginate fixed between the two, according to certain proportion, we prepared lignin xanthate resin loaded on bentonite composite adsorbent, by single factor experiment, we determined the optimum preparation conditions as follows:dosage of sodium alginate was 1.2g, dosage of modified clay was 4.5g, the mass fraction of CaCl2 solution was 3%.The composite sphere looks sleek, sphere rules, the internal hole was rich, the specific surface area was 5.9748m2/g.(4) We researched the adsorption properties of composite sphere towards Hg2+ and doxycycline hydrochloride, the experimental results showed that the saturated adsorption amount of Hg2+ and antibiotics were 27.248 mg/g and 416.67mg/g, the adsorption kinetics equation followed the pseudo-second order kinetic equation; the adsorption isotherm of Hg2+and antibiotics followed the Langmuir model, showed that its adsorption of Hg2+ and antibiotics were monolayer adsorption; dealed with Hg2+solution of 20mg/L, the best adsorbent dosage was 0.28g/50 ml, the Hg2+ removal rate can reach above 95.17%; dealed with 30mg/L of doxycycline hydrochloride solution, the best adsorbent dosage was 0.2g/50ml, the removal rate of doxycycline hydrochloride can reach above 93.57%; studied the composite column sphere to the breakthrough curve of Hg2+, examined the factor of column height、flow velocity and initial concentration to the influence of the penetration curve.