•A new boronate affinity sorbent (BAS) was prepared.•The BAS was used as the extractive medium of stir cake sorptive extraction (SCSE).•The B–N coordination favored the extraction of nitrogen-containing pollutants.•A combination of SCSE–BAS–HPLC/MS/MS was developed.•The combination was applied to monitor ultra-trace sulfonamides in water samples.In this study, a new boronate affinity sorbent based on poly(4-vinylphenylboronic acid-divinylbenzene) monolith (VPB–DB) was prepared and used as extractive medium of stir cake sorptive extraction (SCSE). The effect of the preparation parameters in the polymerization mixture on extraction performance was investigated thoroughly. The sorbent was characterized by infrared spectroscopy, elemental analysis, scanning electron microscopy and mercury intrusion porosimetry. The determination of 8 sulfonamides in environmental water samples with the combination of SCSE and high performance liquid chromatography tandem mass spectrometry detection was selected as a paradigm for the evaluation of extraction performance of poly(VPB–DB) monolith for nitrogen-containing pollutants. Under the optimal extraction conditions, the limits of detection (S/N = 3) and limits of quantification (S/N = 10) for the target analytes were 0.0012–0.010 and 0.0040–0.033 μg/L, respectively. The method also showed good linearity, repeatability, recoveries and high feasibility. At the same time, aromatic amines, nitrophenols, amide herbicides and sudan dyes were also used to evaluate the extractive performance of the sorbent for nitrogen-containing compounds. Results well indicate that the interaction of boron–nitrogen coordination between sorbent and analytes plays a key role in the extraction of nitrogen-containing compounds.

Laboratory batch experiments were conducted in order to assess the impacts of temperature on the performance of goethite in removing arsenate from water. All batch experiments were conducted at four temperatures (30, 50, 70 and 90 °C) and pH 4.6. The results showed that both the arsenic uptake rate and capacity were significantly enhanced with increasing temperature from 30 to 90 °C. The adsorption kinetics followed a pseudo-second-order model with coefficients of determination (R2) all above 0.999. The process followed the Langmuir model, and several thermodynamic parameters were calculated. Arsenate adsorption was facilitated more under simulative geothermal water conditions than in RO (reverse osmosis) water. The crystalline structure of goethite was not changed after adsorption at various temperatures. XPS results showed a decrease in the content of iron hydroxyl groups, which demonstrated that arsenate adsorption onto goethite may be realised through the replacement of the iron hydroxyl group to form inner-sphere bidentate/monodentate complexes at pH 4.6.

•We proposed a crop-specified evaluation framework for managing sewage irrigation.•The framework composes of crop nutrition diagnosis test and phytotoxicity bioassays.•Sewage irrigation deriving phytotoxicity and nutrition input are evaluated simultaneously.•Formulated fertilization and sewage dilution ratio are suggested by cropping stages.•The framework was proved practically feasible with a case study.Sewage dilution and formulated fertilization are cost-effective to avoid sewage-deriving phytotoxicity stress and excess fertilizer application in agricultural sewage irrigation practice. However, it is hard for us to fix the parameters of sewage dilution ratio (SDR) and fertilization formula exactly for the best management of sewage irrigation practice according to those published guidelines. This paper presented such an assessment framework. The assessment tools in the framework consist of four consecutive sewage irrigation experiments, which include germination test, seedling test and cropping test for assessing sewage-deriving phytotoxicity stress in different crop development stages, and DRIS test for diagnosing crop nutrient deficiency. The framework is further verified with crop kale (Brassica oleracea L. var. acephala D.C.) under different pre-set SDR values. The results of germination, seedling and cropping tests can significantly reflect the change of sewage-deriving phytotoxicity with both SDR gradient and crop development stages. Furthermore, the results of DRIS test show that sewage irrigation causes the deficiency of N and P nutrients relative to K nutrient in crop kale. Finally, according to these test results, SDR values and fertilization formula are optimized for guiding the conjunctive use of sewage and fresh water in cropping practice. The framework is thus a best management tool supplementary for those published guidelines to enhance the efficiency and feasibility of agricultural sewage reuse.Download high-res image (223KB)Download full-size image