Polymeric nanoparticles of poly(methyl methacrylate)were obtained by emulsion polymerization techniques in a proce ss of two stages.The particles were functionalized with acrylic acid,curcumin,and fumaramide and three...Polymeric nanoparticles of poly(methyl methacrylate)were obtained by emulsion polymerization techniques in a proce ss of two stages.The particles were functionalized with acrylic acid,curcumin,and fumaramide and three series of polymeric particles were obtained.The incorporation of functional groups was confirmed by Fourier transform-infrared spectrosocopy(FT-IR)and ultraviolet-visible(UV-Vis)methods.The spherical morphology of particles with an average diameter of 100 nm was observed by scartning electron microscopy(SEM).The polymeric materials were used for recovery of[Eu]from synthetic solutions.The nanoparticles show excellent chelation capacity to trap rare-earth ions,because they recover more than 85%of[Eu]at pH of 2.The images of SEM after extraction process show arrays between particles with larger average particle sizes to 1.5 um.In addition,the particles have a good stripping capacity,exceeding 50%of it,maintaining their homogeneity in morphology and good stability in dispersion for the recovery and stripping processes.A pseudo-second model order is obtained for the extraction and stripping processes while the best results of stripping process are obtained at pH of 6.展开更多
The recovery of yttrium is proposed by applying a solid-liquid extraction process using di-2-ethyl hexylphosphoric acid(D2EHPA) as extracting agent.The extracting agents were supported on a macro porous polymeric resi...The recovery of yttrium is proposed by applying a solid-liquid extraction process using di-2-ethyl hexylphosphoric acid(D2EHPA) as extracting agent.The extracting agents were supported on a macro porous polymeric resin XAD-7(solid phase).Yttrium ions extraction and discharge tests were performed,firstly from a synthetic aqueous solution of 100 mg/L Y(liquid phase) at 25℃ with stirring.The effects of pH of aqueous solutions bearing yttrium,volume fraction of extracting agents and the solid/liquid(S/L)ratio on the yttrium recovery were studied.The most favorable conditions for yttrium ions extraction are;20 vol% D_(2)EHPA functionalized resin,pH=1.5 and an S/L ratio of 10 mg/mL The discharge of yttrium ions was done under the same conditions of extraction stage,using a 2 mol/L [H_(2)SO_(4)] as stripping solution.Up to 80% yttrium is extracted,while 75% yttrium is recovered in the striping solution.In all experiments,the reaction equilibrium is reached after 20 min,and the kinetics for the extraction stage was determined as a second-order model.Also,experiments were carried out to discharge the yttriumloaded resins,and it has been determined that the best pH value to strip the Y ions is 1.5.Cyclic tests of extraction and discharge for yttrium ions show that the functionalized resin can work at least five cycles without decreasing its efficiency.Finally,the proposed process was tested in a real solution with Y ions fro m a waste fluorescent la mp powder leached in H_(2)SO_(4),demonstrating the ability to effectively recover yttrium,separating it from various metals from the studied residue.展开更多
基金Project supported by Secretaria de Investigación y Posgrado Instituto Politecnico Nacional(20221369,20231939,2027024,20230751)Consejo Nacional de Humanidades,Ciencia y Tecnologias CONAHCyT。
文摘Polymeric nanoparticles of poly(methyl methacrylate)were obtained by emulsion polymerization techniques in a proce ss of two stages.The particles were functionalized with acrylic acid,curcumin,and fumaramide and three series of polymeric particles were obtained.The incorporation of functional groups was confirmed by Fourier transform-infrared spectrosocopy(FT-IR)and ultraviolet-visible(UV-Vis)methods.The spherical morphology of particles with an average diameter of 100 nm was observed by scartning electron microscopy(SEM).The polymeric materials were used for recovery of[Eu]from synthetic solutions.The nanoparticles show excellent chelation capacity to trap rare-earth ions,because they recover more than 85%of[Eu]at pH of 2.The images of SEM after extraction process show arrays between particles with larger average particle sizes to 1.5 um.In addition,the particles have a good stripping capacity,exceeding 50%of it,maintaining their homogeneity in morphology and good stability in dispersion for the recovery and stripping processes.A pseudo-second model order is obtained for the extraction and stripping processes while the best results of stripping process are obtained at pH of 6.
基金Project supported by Secretariat of Research and Postgraduate Studies National Polytechnic Institute (20221369 and 20231939)Consejo Nacional de Ciencia y Tecnologia CONACyT。
文摘The recovery of yttrium is proposed by applying a solid-liquid extraction process using di-2-ethyl hexylphosphoric acid(D2EHPA) as extracting agent.The extracting agents were supported on a macro porous polymeric resin XAD-7(solid phase).Yttrium ions extraction and discharge tests were performed,firstly from a synthetic aqueous solution of 100 mg/L Y(liquid phase) at 25℃ with stirring.The effects of pH of aqueous solutions bearing yttrium,volume fraction of extracting agents and the solid/liquid(S/L)ratio on the yttrium recovery were studied.The most favorable conditions for yttrium ions extraction are;20 vol% D_(2)EHPA functionalized resin,pH=1.5 and an S/L ratio of 10 mg/mL The discharge of yttrium ions was done under the same conditions of extraction stage,using a 2 mol/L [H_(2)SO_(4)] as stripping solution.Up to 80% yttrium is extracted,while 75% yttrium is recovered in the striping solution.In all experiments,the reaction equilibrium is reached after 20 min,and the kinetics for the extraction stage was determined as a second-order model.Also,experiments were carried out to discharge the yttriumloaded resins,and it has been determined that the best pH value to strip the Y ions is 1.5.Cyclic tests of extraction and discharge for yttrium ions show that the functionalized resin can work at least five cycles without decreasing its efficiency.Finally,the proposed process was tested in a real solution with Y ions fro m a waste fluorescent la mp powder leached in H_(2)SO_(4),demonstrating the ability to effectively recover yttrium,separating it from various metals from the studied residue.