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Achieving advanced treatment of phosphorus (P) to prevent water eutrophication and meet increasingly stringent wastewater discharge standard is an important goal of water management. In this study, a low-cost, high-efficiency phosphate adsorbent zirconium-modified biochar (ZrBC) was successfully synthesized through co-precipitation method, in which the biochar was prepared from the pyrolysis of peanut shell powder. ZrBC exhibited strong adsorption ability to low-concentration phosphate ( 1 mg·L

The activation of peroxymonosulfate (PMS) by Fe(II) or Fe(III) for environmental decontamination is severely limited by the low conversion rate from Fe(III) to Fe(II). Here, we found that this puzzling problem could virtually be solved by introducing trace amounts of S

Based on 130 climate signal indexes provided by National Climate Center of China, this paper established a decision tree diagnostic prediction model for Spring Kuroshio Sea Surface Temperature (SST) from 1961 to 2015 (65 years) by using Chi-Squared Automatic Interaction Detector (CHAID) algorithm in data mining and obtained five rule sets to determine whether Spring Kuroshio SST is high or not. Considering the data of the 44 years from 1961 to 2004 as the training set of the model and the other years as the test set, the training accuracy of the model can reach to 95.45% and the test accuracy can reach to 81.82%. Three types of Spring Kuroshio SST are different in intensity and distribution. The results show that the prediction model of Spring Kuroshio SST based on CHAID algorithm has a high prediction accuracy, with the reasonable and effective model and the well-thought-out decision rules. Moreover, based on the results of decision classification, the SST anomalies correspond to different distribution characteristics of summer daily precipitation anomalies in eastern China, which can provide a new idea and method for climate prediction of regional summer precipitation.

The cathode with low-energy consumption and long-term stability is pivotal to achieve the conversion of nitrate (NO

The internal Fe2+/Fe3+ cycle is important for peroxymonosulfate (PMS) activation by iron-based materials to produce the reactive oxidative species (ROS) for the breakdown of organic contaminants. Previous studies have focused on the contribution of heterogeneous sulfur species to the Fe2+/Fe3+ cycle such as lattice S(-II) and surface SO32– of iron sulfides. In this study, we found that the dissolved S(-II) from mackinawite (FeS) had a substantial contribution to the Fe2+/Fe3+ cycle. Furthermore, the oxidation intermediates of the dissolved S(-II) such as S2O32− and SO32− ions could convert Fe3+ to Fe2+ in solution. The elimination of target organic pollutant bisphenol A (BPA) derived from PMS activation triggered by the dissolved Fe2+ might be enhanced by the equivalent dissolved S(-II) in the FeS/PMS system. These results revealed that previous studies underestimated the significance of PMS activation by dissolved Fe2+ of iron sulfides to organic pollutant degradation. Moreover, SO4•- and •OH were more likely to be the main ROS for BPA degradation in the FeS/PMS system compared with FeO2+. Considering that the metal sulfides have been widely used to activate PMS, H2O2 and peroxydisulfate, this study offers a new perspective on the function of sulfur in these advanced oxidation processes.

Allicin as an active component in allium species being widely present in food waste (FW) and waste activated sludge (WAS). Recently, allicin has been found to inhibit the anaerobic co-digestion. However, few literatures were available related to its impacting on organic matter release and microbial community in anaerobic co-digestion system of FW and WAS. Thus, this work aimed to fill that gap through use a series of batch test under conditions of pH 7 and 35 ± 1 °C. Experimental results showed that the anaerobic co-digestion system almost could not measure methane accumulation before day 20, when allicin dosage was 2.0 μg/L. However, the amount of intracellular material released from FW and WAS to substrate liquid was raised, including organic matter, PO43−-P and NH4+-N. Analysis of microbial community based on high throughput sequencing showed that microbial diversity increased at initial phase of anaerobic co-digestion from FW and WAS, meanwhile, community abundance of Candidatus_Methanofastidiosum raised significantly with co-digestion time. Whereas, methanosaeta abundance was only 19.74% in the allicin test reactor that it was the highest abundance in blank group.

A highly active and selective electrode is essential in electrochemical denitrification. Although the emerging Cu-based electrode has attracted intensive attentions in electrochemical NO3- reduction, the issues such as restricted activity and selectivity are still unresolved. In our work, a binder-free composite electrode (Cu3P/CF) was first prepared by direct growth of copper phosphide on copper foam and then applied to electrochemical NO3- reduction. The resulting Cu3P/CF electrode showed enhanced electrochemical performance for NO3- reduction (84.3%) with high N2 selectivity (98.01%) under the initial conditions of 1500 mg L-1 Cl- and 50 mg N L-1 NO3-. The cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) demonstrated that electrochemical NO3- reduction was achieved through electron transfer between NO3- and Cu0 originated from CF. The in-situ grown Cu3P served as the bifunctional catalyst, the electron mediator or bridge to facilitate the electron-transfer for NO3- reduction and the stable catalyst to produce atomic H* toward NO2- conversion. Meanwhile, the Cu3P/CF remained its electrocatalytic activity even after eight cyclic experiments. Finally, a 2-stage treatment strategy, pre-oxidation by Ir-Ru/Ti anode and post-reduction by Cu3P/CF cathode, was designed for electrochemical chemical oxygen demand (COD) and total nitrogen (TN) removal from real wastewater.

Natural allocolchicine and analogues derived thereof a tricyclic 6-7-6-system have been found as key scaffold of various biologically relevant molecules. However, the direct preparation of the allocolchicine motif remains difficult to date. Herein, we report on an electrooxidative radical cyclization of biarylynones with various carbon- and heteroatom-centered radical precursors