Study On The Adsorption Of Formaldehyde And Ammonia In Water By Modified Camellia Shell Activated Carbon

This paper first introduces the harm of formaldehyde wastewater and ammonia wastewater and common processing methods.For these two types of contaminants use agricultural waste Camellia shell as raw materials,the washing and drying,using potassium carbonate solution and phosphate solution impregnation of Camellia shell,respectively,into potassium carbonate carbon in the nitrogen flow in the modified Camellia shell activated carbon and phosphate modification of Camellia shell activated carbon by infrared spectroscopy,scanning electron microscopy,BET surface area method of three kinds of modern technology on the surface characterization of materials.The two kinds of biomass activated carbon adsorbed formaldehyde and ammonia nitrogen in water.The influence of activator concentration,carbonization temperature,initial concentration of water sample,initial pH value and adsorption time on the adsorption effect was discussed through static adsorption experiments.The adsorption mechanism was discussed by adsorption thermodynamics and kinetics.Characterization results(1)The infrared spectrum showed the activated carbon of Camellia oleifera shell modified by potassium carbonate,and there were mainly functional groups such as O-H,N-H,C-O-C,C=O and C-O during the adsorption process.Phosphoric acid modified Camellia shell activated carbon,in the process of adsorption mainly exist O-H,N-H,C-O-C,C=O,C-O and other functional groups.(2)The specific surface area and pore size analysis showed that the surface area of activated carbon of Camellia shell modified by potassium carbonate was 430.49m3/g,Kong Rong was 0.241cm3/g,the average pore diameter was 2.24 nm,the porosity was 89.53%,and the mesoporous rate was 10.47%,which belonged to micro mesoporous material.The surface area of activated carbon from Camellia oleifera shell modified by phosphoric acid is 1636.92m3/g,Kong Rong is 1.015cm3/g,the average pore size is 2.48 nm,the porosity is 16.49%,and the mesoporous rate is 83.51%,which belongs to micro mesoporous material.(3)The electron microscope scan showed that the surface of the activated carbon of the Camellia oleifera shell modified by potassium carbonate was porous and porous and the pore was developed.The surface of the activated carbon with phosphoric acid modified Camellia oleifera is porous and porous,and the pore is well developed.The experimental results showed(1)In the range of activation temperature and activator concentration set in the experiment,the activation temperature was 750 and the concentration of potassium carbonate was 250g/L,and the adsorption effect of Camellia shell activated carbon on formaldehyde was the best.The adsorption process reached equilibrium at 210 min and was in accordance with the quasi two stage kinetic model.The adsorption process conforms to the Langmuir isothermal adsorption model,and the actual maximum adsorption capacity of formaldehyde can reach 3.79mg/g.Under the most suitable experimental conditions,the removal rate of 0.1g with potassium carbonate modified Camellia oleifera shell activated carbon on 100 m L initial mass of 4mg/L can reach 90.5%,and the adsorption effect is good.The results showed that the increase of activation temperature and concentration of activator was beneficial to the adsorption of ammonia on the activated carbon of Camellia oleifera.The adsorption process reached equilibrium at about 420 min,which was in accordance with the quasi two stage kinetic model.The adsorption process conforms to the Langmuir isothermal adsorption model,and the maximum adsorption capacity of ammonia nitrogen can reach 10.83 mg/g.Under the most suitable experimental conditions,the removal rate of ammonia nitrogen ammonia nitrogen with 100 mL initial mass concentration of 20 mg/L can reach 50.3% and the adsorption effect is good when 0.1g potassium carbonate modified activated carbon from Camellia shell.Potassium carbonate modified Camellia shell activated carbon adsorbed formaldehyde to achieve a shorter balance than the adsorption of ammonia nitrogen,the maximum adsorption capacity of ammonia nitrogen is greater than the maximum adsorption amount of 3.79mg/g to formaldehyde.(2)In the range of activation temperature and activator concentration set in the experiment,the formaldehyde adsorption activation temperature is 550 degrees centigrade,phosphate concentration was 40%,the shell activated carbon adsorption of formaldehyde by the best adsorption process reached equilibrium in 180 min,with the pseudo two order kinetics model.The adsorption process accords with the Langmuir adsorption isotherm model,the maximum adsorption capacity of formaldehyde can reach 4.78mg/g.Under the most suitable experimental conditions,the phosphoric acid modified 0.1g Camellia shell activated carbon have a good formaldehyde removal rate of 100 m L with an initial mass concentration of 5mg/L,and the adsorption efficiency was 92.1%.The results showed that the effect of activated carbon from Camellia oleifera shell at 550 C and 50% phosphoric acid was the best to adsorb ammonia nitrogen in water.The adsorption process reached equilibrium at about 6h,which was in accordance with the quasi two stage kinetic model.The adsorption process conforms to the Langmuir isothermal adsorption model,and the actual maximum adsorption capacity of ammonia nitrogen can reach 12.51mg/g.The phosphoric acid modified Camellia oleifera activated carbon of 0.1g can reach 61% of the ammonia nitrogen removal rate of 100 m L initial mass of 20mg/L,and the adsorption effect is good.The concentration of activator was different in the optimum conditions for the adsorption of formalin and ammonia nitrogen by phosphoric acid modified Camellia oleifera.The equilibrium time of adsorbed formaldehyde was shorter than that of ammonia nitrogen,and the maximum adsorption amount of 12.51mg/g was greater than the maximum adsorption amount of 4.78mg/g to formaldehyde.