Study On The Synthesis Of Supported Nano-iron Materials And The Degradation Mechanism Of Coking Wastewater

Coking wastewater is a typical high-concentration refractory organic wastewater.Its composition is complex,the concentration of pollutants,the toxicity and the color are high,the biodegradability is poor,and the water quality fluctuates significantly.Under the requirements of the new emission standards,the traditional "pretreatment and biochemical treatment" combined process cannot meet the requirements.This requires further advanced treatment to meet the emission standards.In this thesis,on the basis of the traditional Fenton system,sodium bentonite-loaded nano-iron(B-n ZVI)was synthesized and a new type of heterogeneous fenton system was constructed,Based on the ultra-large specific surface area and ultra-high activity of B-n ZVI particles,a large number of micro-batteries are constructed in the solution to form an electro-fenton system to achieve advanced treatment of wastewater.Through the activity detection and characterization analysis of synthetic materials,the results show that the materials have better adsorption performance and higher activity.In order to avoid the interaction of multiple pollutants in the coking wastewater on the exploration of the degradation mechanism of organic matter.In this thesis,potassium hydrogen p Hthalate was used to analyze the organic matter in coking wastewater and reacted with B-n ZVI under various conditions.The experimental results show that under the reaction conditions that the initial concentration of the solution is 800mg/L,the material dosage is 0.6g/L,and the p H=3,the COD removal rate can reach89.9%,and the chemical adsorption is the main reaction.Using potassium cyanide solution to simulate the degradation of cyanide in coking wastewater under various reaction conditions.It shows that the oxidation reaction between B-n ZVI and cyanide occurs,and the best degradation effect is achieved under the reaction condition of p H=5.The actual coking wastewater was used for the experiment.Under the experimental conditions of a reaction temperature of 40°C,a material dosage of 1.6g/L,a reaction time of 180 min,and the p H of 3 and 5,the degradation rate of COD reached 72.4% and 67.68%,cyanide degradation rate is 98.2% and 100%.By comparing the GC-MS spectra of the water samples before and after the reaction,the organic matter content in the coking wastewater before and after the reaction was analyzed.The possible reactions of organic substances such as carbamoyl hydrazide,ethylene oxide,2-N-methoxyethoxyethanol,etc.are discussed.The experimental results show that the heterogeneous Fenton system material B-n ZVI has excellent performance and coking The degradation of organic matter and cyanide in wastewater is very favorable.