Study On The Preparation Of Polystyrene Kinalite Composite Material And Its Removal Of Phenolic Pollutants In Water

With the development of global industrialization,environmental pollution has become more and more serious.Phenolic wastewater has attracted wide attention because of its high toxicity and difficult degradation.Moreover,phenolic wastewater pollution can occur in any water resources system,and very low concentration of phenolic wastewater will still cause serious harm to organisms,so how to treat phenolic wastewater simply and efficiently has become one of the most common problems facing the world.In order to improve the practical application of nanomaterials,two kinds of polystyrene-based nanocomposites(resin-loaded covalent organic frameworks TcBD/D318 and flash freezing polystyrene-loaded zero-valent iron nZVI/PS)were prepared to remove phenol,1-naphthol,4-nitrophenol and 4-chlorophenol to investigate the effect of functional groups on removal efficiency.(1)For polystyrene resin supported covalent organic frameworks TcBD/D318,the adsorption behavior of four phenolic pollutants on TcBD/D318 was investigated.The loading of TcBD is the key reason for the increase of adsorption capacity of composites compared with the original resin.The composite material can also solve the problem of poor solid-liquid separation performance of TcBD,which is difficult to be used on a large scale and easy to agglomerate and deactivate in the use process.In the range of experimental pH,the composites can maintain a large adsorption capacity for all four compounds,and the adsorption capacity reaches the maximum when phenols exist in ionic form under alkaline conditions.It shows that ?-?interaction of aromatic groups between adsorbents and contaminants is the main mechanism of adsorption,and the electrostatic effect also plays a certain role.The adsorption mechanism is verified by Gaussian theoretical calculations.In addition,the composite material has great advantages in practical use.It has good anti-interference effect on the coexistence of ions and humic acids in water.At higher concentration,it can still maintain a high adsorption capacity.Compared with COFs materials which are difficult to recover,composite materials can achieve solid-liquid separation in seconds,thus reducing the difficulty of operation and the cost of treatment of phenolic wastewater.(2)The degradation behavior of four phenolic pollutants on flash freezing polystyrene-loaded zero-valent iron nZVI/PS was investigated by constructing a heterogeneous Fenton-like reaction system of composite materials/hydrogen peroxide.The effects of pH,contact time,zero-valent iron dosage,initial concentration of solution and hydrogen peroxide dosage on the degradation process were investigated.Comparing with iron powder,the composite exhibits stronger pH adaptability due to its high reactivity.Under neutral conditions,it still maintains certain degradation ability for some phenolic substances.Under the optimum degradation conditions obtained by single factor experiments,the degradation rates of phenol,1-naphthol,4-nitrophenol and 4-chlorophenol can reach 98.1%,95.1%,96.4%and 94.8%respectively.The kinetic analysis of each process shows that the degradation process is approximately in accordance with the first-order kinetic model.Composite materials can be recycled by re-loading after use,and the recycling performance is excellent.