| In recent years, high oil-adsorbing resin has attracted a great deal of attention in oily wastewater treatment due to their high adsorption capacity, fast adsorption rate and good regeneration properties. The lignocellulose, butyl methacrylate and the montmorillonite were used as raw materials to prepare lignocelluloses (carboxymethyl cellulose)-g-butyl methacrylate/organic montmorillonite (LNC(CMC)-g-BMA/OMMT) oil-absorptive resin through suspension graft polymerization. The optimum preparation conditions of the oil-absorptive resin were determined by changing the effects of the mass ratio of butyl methacrylate to lignocelluloses (carboxymethylcellulose), the amount of nitiator agent, cross-linking agent, pore-foaming agent, dispersant agent and organic montmorillonite, water-oil ratio and reaction temperature. The morphology and structure of the oil-absorptive resin were inspected and analyzed by means of infrared spectroscope (FT-IR), scanning electron microscope (SEM), X-ray diffraction (XRD) and Brunner-Emmet-Teller (BET). On the optimum preparation conditions, the adsorption characteristics of the oil-absorptive resin were investigated by changing the initial concentrations of oil solution, adsorption time and adsorption temperature. Further more, the adsorption kinetics and adsorption isotherm models of the oil-absorptive resin were determined. Subsequently, the desorption properties of the oil-absorptive resin were studied by solvent extraction. The best desorption conditions of the oil-absorptive resin were determined by changing the amount of ethanol and extraction time.The main experimental results were as follows:1. Synthesis of lignocellulose-g-butyl methacrylate (LNC-g-BMA) oil-absorptive resin and the adsorption/desorption properties of toluene and gasolinePreparation results showed that, the adsorption capacity of LNC-g-BMA for diesel, gasoline and toluene were achieved 8719.7mg/、9086.1 mg/g and 20853.6mg/g, respectively, under the optimum preparation conditions, with the mass ratio of butyl methacrylate to lignocelluloses is 8:1, the amount of nitiator agent, cross-linking agent and pore-foaming agent is 1.2%,1.6% and 50% of all monomers masses respectively. The morphology and structure of the oil-absorptive resin were inspected and analyzed by means of FT-IR, SEM and XRD. The characterization results showed that, butyl methacrylate has been grafted with lignocelluloses, obtained loose and porous LNC-g-BMA oil absorbing resin, which is advantage to the oil molecules spread in the resin; compared with wood cellulose, LNC-g-BMA oil absorbing resin crystallinity decreased obviously. Adsorption results showed that, the adsorption capacity of toluene and gasoline on LNC-g-BMA achieved 20853.6mg/g and 9086.1mg/g after using initial concentration of oil solution 520.2 mg/mL and 402.8 mg/mL, being performed for 180min at 60℃. The sorption processes of LNC-g-BMA were better fitted by pseudo-second-order equation, the Langmuir equation and Freundlich equation. The desorption results showed that, when the stirring speed is 120 r/min, the recovery rate and oil adsorption loss rate of LNC-g-BMA for toluene were 88% and 23% after using desorption agent of 40mL ethanol and magnetic stirring for 30 minutes; the recovery rate and oil adsorption loss rate of LNC-g-BMA for gasoline were 86% and 13% after using desorption agent of 30mL ethanol and magnetic stirring for 40 minutes.2. Synthesis of lignocellulose-g-butyl methacrylate/organic montmorillonite (LNC-g-BMA/OMMT) oil-absorptive resin and the adsorption/desorption properties of gasolinePreparation results showed that, the adsorption capacity of LNC-g-BMA/OMMT was achieved 9873.1mg/g under the optimum preparation conditions, with the water-oil ratio is 8:1, the amount of organic montmorillonite, nitiator agent, cross-linking agent and dispersant agent is 5%,1.3%,1.7% and 10% of all monomers masses respectively. The morphology and structure of the oil-absorptive resin were inspected and analyzed by means of FT-1R, SEM XRD and BET. The characterization results showed that, the C=O and C-O bonds in LNC-g-BMA occurred coordination or complexation with the-OH. Si-O bonds in montmorillonite via cationic in montmorillonite interlayer, obtained loose and porous LNC-g-BMA/OMMT oil absorbing resin, which is advantage to the oil molecules spread in the resin; the inter-layer distance of montmorillonite is enlarged by organophilic modification, LNC-g-BMA intercalated into montmorillonite interlayer via destroying the layer structure of montmorillonite. Adsorption results showed that, the adsorption capacity of gasoline on LNC-g-BMA/OMMT achieved 9648mg/g after using initial concentration of oil solution 402.8mg/mL, being performed for 180min at 60℃. The sorption processes of LNC-g-BMA/OMMT were better fitted by pseudo-second-order equation, the Langmuir equation and Freundlich equation. The desorption results showed that, when the stirring speed is 120 r/min, the recovery rate and oil adsorption loss rate of LNC-g-BMA/OMMT for gasoline were 81% and 14% after using desorption agent of 30mL ethanol and magnetic stirring for 40 minutes.3. Synthesis of carboxymethylcellulose-g-butyl methacrylate/organic montmorillonite (CMC-g-BMA/OMMT) oil-absorptive resin and the adsorption/desorption properties of gasolinePreparation results showed that, the adsorption capacity of CMC-g-BMA/OMMT was achieved 11585.2mg/g under the optimum preparation conditions, with the mass ratio of butyl methacrylate to carboxymethylcellulose is 8:1, the amount of organic montmorillonite, nitiator agent and cross-linking agent is 5%,1.4% and 2.0% of all monomers masses respectively. The morphology and structure of the oil-absorptive resin were inspected and analyzed by means of FT-IR, SEM and XRD. The characterization results showed that, the C=O and C-0 bonds in CMC-g-BMA occurred coordination or complexation with the-OH, Si-O bonds in montmorillonite via cationic in montmorillonite interlayer, obtained loose and porous CMC-g-BMA/OMMT oil absorbing resin, which is advantage to the oil molecules spread in the resin; the inter-layer distance of montmorillonite is enlarged by quaternary ammonium salt organophilic modification, which is beneficial to polymer chain intercalated into montmorillonite interlayer and destroyed the layer structure of montmorillonite, and OMMT exists in the form of intercalation and blend in polymer matrix. Adsorption results showed that, the adsorption capacity of gasoline on CMC-g-BMA/OMMT achieved 11585.2mg/g after using initial concentration of oil solution 402.8mg/mL, being performed for 200min at 70℃. The sorption processes of CMC-g-BMA/OMMT were better fitted by pseudo-second-order equation, the Langmuir equation and Freundlich equation. The desorption results showed that, when the stirring speed is 120 r/min, the recovery rate and oil adsorption loss rate of CMC-g-BMA/OMMT for gasoline were 83% and 11% after using desorption agent of 30mL ethanol and magnetic stirring for 40 minutes. |
PDF Full Text Request