Preparation And Application Of Functional Carbon Materials From Apigenin Extraction Residue

The continuous improvement of social productivity has made the types of human social and economic activities more diverse,and the waste resources generated have become diverse and complex.These wastes not only cause serious pollution to the natural ecological environment,but also threaten the survival and development of human beings.Waste recycling can not only reduce its pollution to the environment,but also create new value as a new resource.Based on the rich active ingredients and rich fiber components in celery,it will be reused with high added value.In this paper,the celery extraction process was screened by single-factor experiment and orthogonal experiment with the waste celery as raw material.The best extraction process of apigenin was as follows:The ratio of material to liquid was1:10,the concentration of ethanol was 50%?wt?,the extraction temperature was 80?,and the extraction was carried out 3 times,each extraction for 3 hours.Under the optimal process conditions,the yield of apigenin can reach 2.78%.The purity of apigenin can be increased from 6.6%to 12.4%by the purification process.The anti-free radical activity comparison experiment was carried out by the celery extract and the apigenin standard respectively,and it shows that the clearance rate of celery extract to free radicals was slightly weaker tha the clearance rate of the apigenin standard,but still had obvious clearing effect.The celery extract has strong scavenging effect on hydroxyl radicals,DPPH radicals and superoxide radicals,and the IC₅₀0 values are 0.080mg/mL,0.067mg/mL,and 0.083mg/mL,respectively.The celery residue which apigenin is extracted is used as a raw material,and the activated carbon material and the carbon nanofiber material are prepared by a chemical activation method and an electrospinning method.The best preparation process for activated carbon is:The activation temperature was 800?,the activation time was 2h,the heating rate was 5?/min,and the activator ratio KOH:C was 1:3.At this time,the carbon material has a nitrogen content of 1.93%,an oxygen content of9.52%,a specific surface area of 364.27m²/g,a specific capacitance of 167F/g,and a charge retention rate of 92.2%.The best preparation process for carbon nanofibers is:The spinning raw material was selected from the celery residue after carboxylation.The spinning ratio of RCS:PAN was 1:9,and the activation ratio was selected as zinc oxalate:the total carbon mass ratio was 1:5.At this time,the specific capacitance of the carbon nanofiber material can reach 276F/g,and the charge retention is 85.1%after charge and discharge 1000 times.The functional carbon nanofibers prepared by doping cobalt,nickel,manganese and other metals by electrospinning were used as catalysts to catalyze the degradation of dye wastewater.The catalysts of different metal-doped carbon nanofibers were studied.It was found that the photocatalytic degradation of methyl orange dye by cobalt-doped carbon nanofibers was the most efficient.The doping amount of cobalt is 1:10,and when the amount of catalyst is 10g/L,the reaction rate is up to 79.71%after 4h reaction.The photocatalyst prepared by cobalt,nickel and manganese composite metal doped carbon nanofibers has the highest degradation efficiency.The metal doping amount is 1:10,the catalyst dosage is 7g/L,and the removal rate of the reaction is up to 90.79%.