近日，欧洲杯官方最新买球app下载水利与环境学院赵艳侠教授课题组在环境领域顶级期刊《欧洲杯买球》上发表了题为“An innovative exploration to identify and isolate the dominant-flocculated-species from polytitanium chloride synthesized by electrodialysis”的学术论文。Hou Mingqian, graduate student of Grade 2022, is the first author, and her supervisor Professor Zhao Yanxia is the corresponding author of the paper。

FIG. 1 Mechanism and coagulation effect of ultrafiltration separation of dominant flocculating species

The abundance of dominant flocculating species is the key to determining the coagulant's coagulability。Titanium-based coagulants have attracted much attention due to their high coagulant efficiency, but how to identify and isolate the main flocculating species is a current challenge。Previously, our research group precisely controlled titanium hydrolytic species and OH^- Polytitanium chloride (PTC) rich in superior flocculating species was successfully synthesized by electrodialysis (ED).。

Subsequently, by one-step rapid ultrafiltration separation (UF), PTC was reduced to 0.PTC-5k, which is rich in dominant flocculating species, was successfully isolated by interception of 5 kDa ultrafiltration membrane (made of polyether sulfone) at 12 MPa nitrogen pressure。The results of electrospray time-of-flight mass spectrometry (ESI-TOF-MS) show that the main flocculants in PTC-5k are small and medium titanium hydrolyzed species with a large proportion of signal concentration between m/z values of 100 and 500。Compared with PTC, the amount of PTC used by this dominant flocculating species decreased by 33 percent.Under the premise of 0%, the removal rate of organic pollutants increased by about 15%.0%。TEM showed that PTC-5k had a unique snowflake branch structure, which enhanced the flocculation ability of mesh cloth rolling and adsorption bridge。Compared with PTC, the flocculation formed by PTC-5K is more compact。Therefore, the membrane pollution is greatly reduced in the cross-flow filtration of the coagulation-coupled ceramic membrane。

The coagulation effect experiment showed that PTC-5K was better than PTC in removing organic pollutants。Compared with PTC, PTC-5K increased the removal rate of organic matter by about 15 percent.0%。In addition, PTC-5k has been shown to be very effective in reducing turbidity levels, with a residual turbidity of about 1 at optimal doses.At 79 NTU, the DOC removal efficiency of PTC-5K is 10%−20% higher than that of PTC。At the optimal dose, PTC-5k significantly increased UV₂₅₄And DOC removal rates increased by 15% and 11%, respectively.6%。Subsequently, the specific advantages of PTC-5k in organic matter removal were discussed using SEC-OCD-OND tests。 The BP removal rate of PTC-5k was 54%。For ammonia, the removal rate by coagulation is about 40%。

Figure 2. Concrete effect of PTC-5k

The research results of this paper not only separated titanium-based flocculants by one-step rapid separation method, but also realized the successful separation of titanium-based dominant flocculant species, which provided great reference value for the purification of flocculants, the improvement of coagulation effect, environmental protection and the practical application of membrane filtration mixing technology。This research was supported by the National Natural Science Foundation of China, the Shandong Taishan Scholars Young Experts Program and the Shandong Outstanding Youth Innovation Team Program。Paper link:http://www.sciencedirect.com/science/article/pii/S0043135424004172

Written by Hou Mingqian Edited by Zhang Yajing Edited by Zhang Wei