Study on the adsorption of nickel ions in wastewater by modified synthetic zeolite
ZENG Yuxiang
LIAO Yingmin
ZHANG Jing
Abstract：Modified artificial zeolite has unique ion exchange and adsorption properties,which can effectively remove nickel ions Ni(Ⅱ)in wastewater.Therefore,the research on the adsorption of heavy metal Ni(Ⅱ)in wastewater by low-cost modified artificial zeolite could provide reference and data support for the related research on environmen-tal treatment of heavy metal pollution.The artificial zeolite prepared from coal-based solid waste was modified by high temperature activation method.The Ni(Ⅱ)simulated waste water solution was treated by static adsorption method.Single factor experiment,orthogonal experiment,kinetic study and isothermal adsorption study were carried out to explore the feasibility and adsorption effect of modified artificial zeolite on Ni(Ⅱ)adsorption,and to explore its ad-sorption mechanism.The results of single factor experiment showed that the modification effect of artificial zeolite was the best when calcined at 500℃for 1.5 h.The removal rate of Ni(Ⅱ)increased with the increase of dosage and adsorption time,and finally stabilized.Also,the removal rate of Ni(Ⅱ)increased with the increase of oscillation temperature,and increased first and then decreased with the increase of pH.Neutral solution and high temperature conditions were conducive to the purification of wastewater containing Ni(Ⅱ).The results of orthogonal experiments showed that the dosage of modified artificial zeolite had the greatest influence on the removal rate,while the oscilla-tion temperature had the least influence on the removal rate.There was no significant difference among the different levels of the four influencing factors of the dosage of modified artificial zeolite,adsorption time,pH and oscillation temperature.Under the optimal adsorption conditions of modified artificial zeolite dosage of 0.8 g,adsorption time of 200 min,pH of 7,oscillation temperature of 55℃,and oscillation rate of 160 r/min,the removal rate of 50 mg/L Ni(Ⅱ)wastewater by modified artificial zeolite could reach 99.99%,which could meet the requirements of GB 8978-1996 Integrated Wastewater Discharge Standard.The entire adsorption process followed the pseudo-second-order kinetic model and Langmuir adsorption isotherm,which was dominated by monolayer chemical adsorption,with a maximum ad-sorption capacity of 153.85 mg/g.Modified artificial zeolite can efficiently adsorb Ni(Ⅱ)in wastewater,and has good application and development prospects in the treatment of heavy metal wastewater.
Keywords：modified artificial zeolitenickel ionsadsorption mechanismremoval ratedosagekinetics modelstatic adsorption methodoscillation temperature
Publication Date：2023-11-10
Pages：8( 13-20 )