Preparation Of Modified Volcanic Slag Filter And Its Application In Water Treatment

Volcanic slag is a kind of slag-like porous rock which is formed by magma passing through the volcanic channel and being cooled after high-temperature combustion during volcanic eruption.It has a wide range of sources,low cost and convenient mining.Good engineering nature.The reserves of volcanic slag resources are very rich in Jilin province,which has exceeded 30 million m3,ranking the first in the country in China.At present mainly used in the building materials industry.In order to solve the high cost of increasing water pollution,excessive water treatment costs and low added value of pozzolan products,this study used pozzolan as an adsorbent to determine the preparation conditions of PFC(polyferric)chloride and ferric chloride modified pozzolans and at the same time the characterization was carried out,and the application research on the removal of heavy metal nickel and organic phenol by modified pozzolans was carried out,which can greatly reduce the cost of water treatment and provide technical support for the application of pozzolans in the water treatment industry.The main contents include:(1)Preparation and Characterization of PFC Modified Volcanic SlagThe performance test of the volcanic slag,the experimental results show that the sum of the crushing rate and the wear rate of the volcanic slag Cb=3.24%,the mud content Cs=0.21%,the hydrochloric acid solubility rate Cha=0.34%,and the void rate ? =46% The standard of artificial ceramsite filter material for water treatment can be used as an adsorbent.The method of coating modification was used to prepare PFC modified volcanic slag.The effects of PFC concentration,soaking time and calcination temperature on the preparation effect were investigated,and the best preparation process conditions were determined.Characterization and analysis of the surface morphology and specific surface area of the volcanic slag before and after modification: the porosity of the volcanic slag after PFC modification increases and the surface roughness increases significantly.The specific surface area increased from 0.3008mm2/g to 0.9075m2/g,which was 3.02 times that of the original slag.(2)Study on adsorption of nickel by PFC modified Volcanic SlagThe effects of the amount of PFC modified volcanic slag,p H of the system,adsorption temperature,adsorption time and initial nickel concentration on the adsorption process were investigated,and the optimal adsorption process conditions were determined.Under this condition,the removal of nickel by PFC modified volcanic slag The rate has increased by 39.63%,with a maximum of 79.91%.The adsorption isotherm of nickel by PFC modified slag conforms to the Freundlich adsorption model,and the adsorption process conforms to the quasi-first-order adsorption kinetic model.(3)Preparation and Characterization of Fe Cl3 Modified Volcanic SlagFe Cl3 was selected as the coating agent to modify the volcanic slag.The effects of Fe Cl3 concentration,soaking time and calcination temperature on the preparation effect were investigated,and the best preparation process conditions were determined.Characterization and analysis of the surface morphology and specific surface area of the volcanic slag before and after modification: After the Fe Cl3 modification,a multi-layer?-Fe2O3 film was was attached to the surface of the volcanic slag,the roughness increased significantly,and the specific surface area increased from 0.3008m2/g to 0.9083m2/g,which was 3.02 times of the original volcanic slag.(4)Adsorption of Phenol with Fe Cl3 Modified Volcanic SlagThe effect of adsorption temperature,adsorption time,system p H value,amount of Fe Cl3 modified porosity slag and initial concentration of phenol on the adsorption process was investigated,and the optimal adsorption process conditions were determined.The removal rate has been increased by 36.09%,with a maximum of 76.72%.The adsorption isotherm of phenol by Fe Cl3 modified volcanic slag conforms to Langmuir adsorption model and Freundlich adsorption model,and the adsorption process conforms to quasi-first-order adsorption kinetic model.Volcanic slag can be used as an adsorbent to treat nickel-containing and phenol-containing wastewater,which has the advantages of fast adsorption rate and low cost.