| Sugar filter mud is rich in organic matter such as cellulose,lignin,protein,fat,sugar,etc.,as well as inorganic ingredients,which is a typical solid waste in the sugar industry.Due to the complex composition of the sugar filter,high water content and extremely perishable odor,it is difficult to obtain an ideal disposal method,which limits its high value comprehensive utilization.At present,researches on solving the problem of sugar sludge pollution and high value utilization have yielded more results.Numerous studies have shown that sugar filter sludge has extremely high utilization value and research significance.However,there are still many things to be explored in the use of sugar filter sludge as a raw material for the preparation of adsorbents and for the treatment of printing and dyeing wastewater.In this paper,the adsorption performance and kinetics of the sugar filter adsorbent are studied,which aims to provide basic theoretical support for the comprehensive utilization of sugar sludge.The main research contents and results are as follows:?1?High temperature modification of sugar filter,preparation of activated carbon and structural characterization of adsorbent.The adsorbent was characterized by Fourier transform infrared spectroscopy,specific surface area and pore size analyzer and scanning electron microscope.The high temperature modified sugar filter mud was compared with the sugar filter mud modified at different temperatures,and it was found that the specific surface area of the modified sugar filter sludge at 300°C was39.847 m 2·g-1,which was favorable for adsorption.The structure of the sugar filter after calcination at a high temperature becomes looser and has a small number of pores.Activated carbon is prepared by using sugar mill sludge as raw material and phosphoric acid as activator.Through the single factor experiment and orthogonal experiment,the optimum preparation conditions of activated sugar activated sugar were determined by iodine adsorption value and yield index:the activator mass fraction was 30%,the liquid-to-liquid ratio was 2.5:1,and the activation time was at120 min,the activation temperature was 400°C.At this time,the iodine adsorption value of the activated sugar activated carbon was 311.42 mg·g-1,and the yield was34.30%.The activated sugar activated carbon has a specific surface area of 100.631m2·g-1,a total pore volume of 0.292 cm3·g-1,and an average pore diameter of 3.825nm.The activated carbon of the sugar filter sludge activated by the addition of phosphoric acid has a pore structure,and the pore size and distribution are not uniform,mainly mesopores.It can be seen from the infrared spectrum that the prepared sugar filter adsorbent has undergone great changes in chemical composition.?2?Study on the adsorption performance and kinetics of high temperature modified sugar filter on Congo red.The adsorption experiment of simulated wastewater was carried out by static adsorption method.The effects of Congo red initial concentration,adsorption time,adsorbent dosage and pH value on decolorization rate and adsorption amount were investigated.The optimum adsorption decolorization conditions were determined.The pseudo-secondary and intraparticle diffusion equations simulate the kinetic behavior of modified Congo red by modified sugar filter.The results of adsorption performance study showed that when the initial concentration of Congo red was 100 mg·L-1,the adsorption time was 120 min,the dosage of adsorbent was 0.1 g and the pH value was 6,the decolorization rate and adsorption capacity of wastewater were 97.22%and 32.40 mg.g-1;kinetic study results show that the pseudo-secondary kinetic mechanism is more suitable to explain the adsorption behavior of Congo red by high temperature modified sugar filter.The high temperature modified sugar filter mud is an excellent adsorbent which can be used for the adsorption of Congo red.?3?Study on the adsorption performance and kinetics of high temperature modified sugar filter on methylene blue.The adsorption experiment of simulated wastewater was carried out by static adsorption method.The effects of different initial concentration of methylene blue,adsorption time and dosage of adsorbent on decolorization rate and adsorption amount were investigated.The optimum adsorption and decolorization conditions were determined.The intraparticle diffusion equations simulate the kinetic behavior of the modified sugar filter to adsorb methylene blue.The results of adsorption performance study showed that when the adsorption time was 120 min and the dosage of adsorbent was 0.18 g,the decolorization rate and adsorption capacity of wastewater were 77.77%and 24.09 mg·g-1.The kinetic study showed that pseudo-secondary power The mechanism of the equation is more suitable to explain the adsorption behavior of methylene blue by high temperature modified sugar filter.?4?Study on the adsorption performance and kinetics of activated sugar activated carbon on dye wastewater Rhodamine B.The effects of different initial concentrations,adsorption time,adsorbent dosage and pH on the adsorption of rhodamine B on activated sugar by glucose filter were investigated.The adsorption of rhodamine B by activated carbon was simulated by pseudo-primary,pseudo-secondary and intraparticle diffusion equations.The kinetic behavior of Langmuir and Freundlich adsorption isothermal simulation of sugar filter activated carbon adsorption of rhodamine B thermodynamic behavior.The results showed that when the initial concentration was 100 mg·L-1,the adsorption time was 120 min,the adsorbent dosage was 0.1 g,and the pH value was 4,the decolorization rate of wastewater was up to99.81%,and the adsorption amount was 25.02 mg.g-1;kinetic study results show that the pseudo-second-order kinetic equation mechanism is more suitable to explain the adsorption behavior of rhodamine B on activated sugar activated sugar,and the adsorption energy of activated carbon on adsorption of rhodamine B is better than Langmuir monolayer adsorption model. |
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