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In the present study, the benefits of a Fenton-like treatment process in enhancing the dewaterability of drinking water treatment sludge have been investigated. It is found that using a vacuum electro-osmosis dewatering reactor often results in a low dewatering efficiency, while it can be improved significantly (by about 63% under the optimal condition) by adding the Fenton-like process in combination with acidification. The results based on the three-dimensional (3D) excitation–emission matrix fluorescence spectroscopy and Fourier-transformed infrared spectroscopy indicated that the sludge treated by the Fenton-like process could make fulvic acid-like substances disappear such that the extracellular polymeric substances (EPS) is broken and the dewaterability efficiency is improved. Furthermore, the scanning electronic microscopy analysis and particle size distribution analysis showed that the Fenton-like process and acidification destroyed the stable sludge flocs such that the water trapped in the flocs could be released easily and the dewaterability efficiency was enhanced. The 3D response surface of the water removal efficiency evidenced that the optimal operating parameters were Fe 3+ dosage of 54 mg g −1 sludge, H 2 O 2 dosage of 87 mg g −1 sludge and pH of 6.3. The results obtained in this study are expected to provide guidance and support for using the Fenton-like treatment process together with acidification to dewater drinking water treatment sludge. [ABSTRACT FROM AUTHOR]

An ordered macro-microporous single-crystalline MOF with micron-sized hollow exhibits a recorded CrO 4 2- adsorption capacity of 609 mg/g, and offers the promising application for CrO 4 2- disposal in nuclear waste. [Display omitted] • A rarely hollow single-crystalline framework 1 with ordered macro-micropores. • MOF 1 possesses the record CrO 4 2- adsorption capacity of 609 mg/g. • MOF 1 can maintain its high CrO 4 2- adsorption capacity after 400 kGy β irradiation. • 1 offers the promising practical application for CrO 4 2- disposal. The vitrification process represents an effective method for high-level radioactive waste disposal, but CrO 4 2- can form crystalline spinels within the glass to cause the secondary leak of radioactive waste. Porous materials are widely used for trapping CrO 4 2-, but the unsatisfied adsorbing capacity and poor selectivity of reported materials make CrO 4 2- enrichment to be a challenging issue. Herein, a rarely hollow single-crystalline MOF (1) with ordered macro-micropores of 13 μm and 8.6 Å was obtained, exhibiting high N 2 adsorption of 339.2 cm3/g and large BET surface area of 1150 m2/g. Cooperation effect between microporous frameworks and micron-sized channels in crystals endows 1 with excellent chromate removal capacity of 609 mg/g, which is a record value known to date among the anion-exchange materials for CrO 4 2- removal. The kinetic analysis revealed that such adsorption was a pseudo-second-order adsorption process. Framework 1 possessed high pH stability and irradiation resistance, can repeatedly absorb/desorb CrO 4 2- to some degree. More importantly, sample 1 can maintain its high CrO 4 2- adsorption capacity after 400 kGy β irradiation, offering the promising application for CrO 4 2- disposal in high-level radioactive waste. [ABSTRACT FROM AUTHOR]