CdS/ZnS-PVDF/PSF光催化膜的制备及其刚果红降解性能研究

Preparation of CdS/ZnS-PVDF/PSF Photocatalytic Membrane and Its Degradation Performance of Congo Red

光催化膜分离耦合技术处理废水是水处理研究方向之一,它是将膜分离技术与光催化技术结合,有效地解决了催化剂回收难的问题,同时也缓解了膜污染问题。利用水热法制备了CdS和CdS/ZnS光催化剂,用相转化法分别制备出聚偏氟乙烯/聚砜(PVDF/PSF)膜,以及CdS和CdS/ZnS光催化剂嵌入其中的CdS-PVDF/PSF光催化膜和CdS/ZnS-PVDF/PSF光催化膜。将刚果红溶液作为污染物,氙灯作为光源,分别对这3种膜的膜通量、截留率和刚果红降解率进行测试比较和分析。结果表明:反应进行360 min后,CdS/ZnS-PVDF/PSF光催化膜的膜通量能够达到63.0 L·h^(-1)·m^(2),相比PVDF/PSF膜(36.0L·h^(-1)·m^(2))和CdS-PVDF/PSF光催化膜(52.1L·h^(-1)·m^(2))的膜通量有显著增加,说明CdS/ZnS的负载有效缓解了PVDF/PSF膜的膜通量由于刚果红分子堵塞孔道引起的衰减。在膜通量增加的同时,CdS/ZnS-PVDF/PSF光催化膜的截留率在360min后依然保持在100%。CdS/ZnS-PVDF/PSF光催化膜对刚果红的降解率可以达到86.9%,分别比使用PVDF/PSF膜和CdS-PVDF/PSF光催化膜提高了18.1%和6.2%。CdS/ZnS-PVDF/PSF光催化膜能够获得最高的膜通量和降解率,因此用于降解废水中的有机污染物具有很好的应用前景。

Photocatalytic membrane separation coupled technology for wastewater treatment is one of the research directions in water treatment.Photocatalytic membrane technology is a combination of membrane separation technology and photocatalytic technology,which effectively solves the problem of difficult photocatalyst recovery and also alleviates the problem of membrane pollution.CdS and CdS/ZnS photocatalysts were prepared by hydrothermal method,and polyvinylidene fluoride/polysulfone(PVDF/PSF)membrane,CdS-PVDF/PSF photocatalytic membrane and CdS/ZnS-PVDF/PSF photocatalytic membrane were prepared by using the phase conversion method.Congo red was used as a pollutant,and xenon lamp was used as a light source.The membrane flux,rejection and degradation ratios of Congo red by using these three membranes were tested,compared and analyzed.The results showed that the membrane flux of CdS/ZnS-PVDF/PSF photocatalytic membrane could reach 63.0 L·h^(-1)·m^(2)for 360 min,which was significantly increased compared to 36.0 L·h^(-1)·m^(2)of PVDF/PSF membrane and 52.1 L·h^(-1)·m^(2)of CdS-PVDF/PSF photocatalytic membrane,indicating that the loading of CdS/ZnS effectively alleviated the attenuation of PVDF/PSF membrane flux due to Congo red molecules blocking the pore.While the membrane flux increased,the rejection of Congo red by using the CdS/ZnS-PVDF/PSF photocatalytic membrane remained at 100%after 360 min.The degradation ratio of Congo red by using CdS/ZnS-PVDF/PSF photocatalytic membrane reached 86.9%after 360 min,which was 18.1%and 6.2%higher than that by using PVDF/PSF membrane and CdS-PVDF/PSF photocatalytic membrane,respectively.The CdS/ZnS-PVDF/PSF photocatalytic membrane can achieve the highest membrane flux and degradation ratio,which has a good application prospect for the degradation of organic pollutants in wastewater.