Nitrite improved nitrification efficiency and enriched ammonia-oxidizing archaea and bacteria in the simultaneous nitrification and denitrification process.

Simultaneous nitrification and denitrification (SND) is effective and energy-saving for wastewater treatment. As an inevitable intermediate product in the SND process, nitrite affects the efficiency of ammonia oxidation and the composition of nitrifiers. To investigate the impact of nitrite on ammonia oxidation efficiency, two reactors performing SND were respectively operated without nitrite (R1 as control) and with 20 mg N/L nitrite addition (R2 as experimental).

Microbial community dynamics and metagenomics reveal the potential role of unconventional functional microorganisms in nitrogen and phosphorus removal biofilm system.

The conventional functional microorganisms for nitrogen and phosphorus removal, such as Nitrosomonas, Nitrobacter, Nitrospira and Candidatus Accumulibacter, were hotspots in past research. However, the role of diverse unconventional functional microorganisms was neglected. In this study, a biofilm system was developed to explore the potential role of unconventional functional microorganisms in nutrients removal.

Insights into simultaneous nitrogen and phosphorus removal in biofilm: The overlooked comammox Nitrospira and the positive role of glycogen-accumulating organisms.

Simultaneous nitrogen and phosphorus removal (SNPR) biofilm system is an effective wastewater treatment process. However, the understanding on the mechanism of functional microorganisms driving SNPR is still limited, especially the role of complete ammonia oxidation (comammox) Nitrospira and glycogen-accumulating organisms (GAO). In this study, a sequencing batch biofilm reactor (SBBR) performing SNPR was operated for 249 d.

Removal of Sb(III) by 3D-reduced graphene oxide/sodium alginate double-network composites from an aqueous batch and fixed-bed system.

We created 3D-reduced graphene oxide/sodium alginate double network (GAD) beads to address the problem of local water pollution by antimony. GAD is a novel material with the high specific surface area of graphene and biosecurity of sodium alginate. Due to the introduction of graphene, the thermal stability and specific surface area of GAD are enhanced, as shown from the FTIR, TGA, BET, Raman, and XRD characterizations.

Removal of Mn (II) by Sodium Alginate/Graphene Oxide Composite Double-Network Hydrogel Beads from Aqueous Solutions.

After the successful preparation of empirical double network hydrogel beads from graphene oxide/sodium alginate(GO/SA), its cationic metal adsorption performance in aqueous solutions were investigated. Taking Mn(II) as an example, the contribution of several factors including pH, bead dosage, temperature, contact time and initial concentration ions to adsorption efficiency were examined. The Transmission Electron Microscopy (TEM) results indicate that the GO/SA double (GAD) network hydrogel bead strongly interpenetrate and the adsorption of Mn(II) is mainly influenced by solution pH, bead dose and temperature.

Synthesis, Characterization, and Adsorptive Properties of FeO/GO Nanocomposites for Antimony Removal.

A magnetic FeO/GO composite with potential for rapid solid-liquid separation through a magnetic field was synthesized using GO (graphene oxide) and FeO (ferriferous oxide). Characterization of FeO/GO used scanning electron microscope (SEM), X-ray diffractometer (XRD), Fourier transform infrared spectrometer (FT-IR), and Vibrating Sample Magnetometer (VSM). A number of factors such as pH and coexisting ions on adsorbent dose were tested in a series of batch experiments.

[The Preparation and Characterization of a New Solid Coagulant: Polymeric Ferric Silicate Sulfate].

As one of the most important water treatment agents, polysilicate coagulant, has been playing an important role in coagulation- flocculation, but it is prone to lose stability due to self-polymerization and the forming of silica gel. Therefore, research on the preparation of stable polysilicate coagulant has attract great attention. A new method to prepare a stable polysilicate coagulant (PSPF), was proposed in this paper.