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Biological conversion pathways of sulfate reduction ammonium oxidation in anammox consortia

Zhen Bi, Deqing Wanyan, Xiang Li, Yong Huang

《环境科学与工程前沿(英文)》 2020年 第14卷 第3期 doi: 10.1007/s11783-019-1217-1

摘要: The SRAO phenomena tended to occur only under certain conditions. High amount of biomass and non-anaerobic condition is requirement for SRAO. Anammox bacteria cannot oxidize ammonium with sulfate as electron acceptor. AOB and AnAOB are mainly responsible for ammonium conversion. Heterotrophic sulfate reduction mainly contributed to sulfate conversion. For over two decades, sulfate reduction with ammonium oxidation (SRAO) had been reported from laboratory experiments. SRAO was considered an autotrophic process mediated by anammox bacteria, in which ammonium as electron donor was oxidized by the electron acceptor sulfate. This process had been attributed to observed transformations of nitrogenous and sulfurous compounds in natural environments. Results obtained differed largely for the conversion mole ratios (ammonium/sulfate), and even the intermediate and final products of sulfate reduction. Thus, the hypothesis of biological conversion pathways of ammonium and sulfate in anammox consortia is implausible. In this study, continuous reactor experiments (with working volume of 3.8L) and batch tests were conducted under normal anaerobic (0.2≤DO<0.5 mg/L) / strict anaerobic (DO<0.2 mg/L) conditions with different biomass proportions to verify the SRAO phenomena and identify possible pathways behind substrate conversion. Key findings were that SRAO occurred only in cases of high amounts of inoculant biomass under normal anaerobic condition, while absent under strict anaerobic conditions for same anammox consortia. Mass balance and stoichiometry were checked based on experimental results and the thermodynamics proposed by previous studies were critically discussed. Thus anammox bacteria do not possess the ability to oxidize ammonium with sulfate as electron acceptor and the assumed SRAO could, in fact, be a combination of aerobic ammonium oxidation, anammox and heterotrophic sulfate reduction processes.

关键词: Anammox bacteria     Autotrophic     Biological conversion     Sulfate reducing ammonium oxidation (SRAO)    

Thermal decomposition mechanism of ammonium sulfate catalyzed by ferric oxide

Xingfu SONG, Jingcai ZHAO, Yunzhao LI, Ze SUN, Jianguo YU

《化学科学与工程前沿(英文)》 2013年 第7卷 第2期   页码 210-217 doi: 10.1007/s11705-013-1320-y

摘要: The decomposition mechanism of ammonium sulfate catalyzed by ferric oxide was investigated in this paper. The decomposition kinetics parameters were determined via a global optimization of the Kissinger iterative method using the non-isothermal thermogravimetric analysis data. The products and intermediates were synchronously characterized by X-ray diffraction and mass spectrometry. The obtained results indicate that the decomposition process of ammonium sulfate catalyzed by ferric oxide can be divided into four stages of which the activation energies are 123.64, 126.58, 178.77 and 216.99 kJ·mol respectively. The decomposition mechanisms at the first and the fourth stage both belong to Mample power theorem, the second stage belongs to Avrami-Erofeev equation and the third belongs to contracting sphere (volume) equation. The corresponding pre-exponential factors ( ) are calculated simultaneously.

关键词: ammonium sulfate     decomposition kinetics     ferric oxide     thermogravimetric analysis    

Effects of SO

Quanming Liang, Jian Li, Hong He, Wenjun Liang, Tiejun Zhang, Xing Fan

《环境科学与工程前沿(英文)》 2017年 第11卷 第4期 doi: 10.1007/s11783-017-0926-6

摘要: The CeO -V O -WO /TiO (CeO -VWT) catalysts were prepared by one-step and two-step impregnation methods. The effects of different loading of CeO and different preparation methods on De-NO activity of catalysts had been investigated. CeO helped to improve the De-NO activity and sulfur resistance. The optimal loading of CeO was 3% with the De-NO efficiency reached 89.9% at 140°C. The results showed that the De-NO activity of 3% CeO -VWT catalysts by one-step method was the same as two-step method basically and reached the level of industrial applications, the N selectivity of catalysts was more than 99.2% between 110°C and 320°C. In addition, CeO promoted the oxidation of NO to NO , which adsorbed on the Lewis acid site (V ═O) to form V ═NO and inspired the fast SCR reaction. Not only the thermal stability but also the De-NO activity of catalysts decreased with excess CeO competed with V O . Characterizations of catalysts were carried out by XRF, BET, XRD, TG and FT-IR. BET showed that the specific surface area of catalysts decreased with the loading of CeO increased, the active components content and specific surface area of catalysts decreased slightly after entering SO . Ammonium sulfate species were formed in poisoned catalyst which had been investigated by XRF, BET, TG and FT-IR. The largest loss rate of weight fraction was 0.024%·°C at 380°C–390°C, which was in accordance with the decomposition temperature of NH HSO and (NH ) SO .

关键词: Low temperature SCR     De-NOx activity     Sulfur resistance     Ammonium sulfate    

Effects of natural zeolite and sulfate ions on the mechanical properties and microstructure of plastic

《结构与土木工程前沿(英文)》 2022年 第16卷 第1期   页码 86-98 doi: 10.1007/s11709-021-0793-x

摘要: One of the strategic materials used in earth-fill embankment dams and in modifying and preventing groundwater flow is plastic concrete (PlC). PlC is comprised of aggregates, water, cement, and bentonite. Natural zeolite (NZ) is a relatively abundant mineral resource and in this research, the microstructure, unconfined strength, triaxial behavior, and permeability of PlC made with 0%, 10%, 15%, 20%, and 25% replacement of cement by NZ were studied. Specimens of PIC-NZ were subjected to confined conditions and three different confining pressures of 200, 350, and 500 kPa were used to investigate their mechanical behavior and permeability. To study the effect of sulfate ions on the properties of PlC-NZ specimens, the specimens were cured in one of two different environments: normal condition and in the presence of sulfate ions. Results showed that increasing the zeolite content decreases the unconfined strength, elastic modulus, and peak strength of PlC-NZ specimens at the early ages of curing. However, at the later ages, increasing the zeolite content increases unconfined strength as well as the peak strength and elastic modulus. Specimens cured in the presence of sulfate ions indicated lower permeability, higher unconfined strength, elastic modulus, and peak strength due to having lower porosity.

关键词: plastic concrete     sulfate resistance     natural zeolite     triaxial compression test     SEM     permeability    

A time−space porosity computational model for concrete under sulfate attack

《结构与土木工程前沿(英文)》 2023年 第17卷 第10期   页码 1571-1584 doi: 10.1007/s11709-023-0985-7

摘要: The deterioration of the microscopic pore structure of concrete under external sulfate attack (ESA) is a primary cause of degradation. Nevertheless, little effort has been invested in exploring the temporal and spatial development of the porosity of concrete under ESA. This study proposes a mechanical–chemical model to simulate the spatiotemporal distribution of the porosity. A relationship between the corrosion damage and amount of ettringite is proposed based on the theory of volume expansion. In addition, the expansion strain at the macro-scale is obtained using a stress analysis model of composite concentric sphere elements and the micromechanical mean-field approach. Finally, considering the influence of corrosion damage and cement hydration on the diffusion of sulfate ions, the expansion deformation and porosity space−time distribution are obtained using the finite difference method. The results demonstrate that the expansion strains calculated using the suggested model agree well with previously reported experimental results. Moreover, the tricalcium aluminate concentration, initial elastic modulus of cement paste, corrosion damage, and continuous hydration of cement significantly affect concrete under ESA. The proposed model can forecast and assess the porosity of concrete covers and provide a credible approach for determining the residual life of concrete structures under ESA.

关键词: expansion deformation     porosity     internal expansion stress     external sulfate attack     mechanical–chemical coupling model    

Effects of two transition metal sulfate salts on secondary organic aerosol formation in toluene/NO

Biwu CHU, Jiming HAO, Junhua LI, Hideto TAKEKAWA, Kun WANG, Jingkun JIANG

《环境科学与工程前沿(英文)》 2013年 第7卷 第1期   页码 1-9 doi: 10.1007/s11783-012-0476-x

摘要: Aerosol phase reactions play a very important role on secondary organic aerosol (SOA) formation, and metal-containing aerosols are important components in the atmosphere. In this study, we tested the effects of two transition metal sulfate salts, manganese sulfate (MnSO ) and zinc sulfate (ZnSO ), on the photochemical reactions of a toluene/NO photooxidation system in a 2 m smog chamber. By comparing photochemical reaction products of experiments with and without transition metal sulfate seed aerosols, we evaluated the effects of transition metal sulfate seed aerosols on toluene consumption, NO conversion and the formation of ozone and SOA. MnSO and ZnSO seed aerosols were found to have similar effects on photochemical reactions, both enhance the SOA production, while showing negligible effects on the gas phase compounds. These observations are consistent when varying metal sulfate aerosol concentrations. This is attributed to the catalytic effects of MnSO and ZnSO seed aerosols which may enhance the formation of condensable semivolatile compounds. Their subsequent partitioning into the aerosol phase leads to the observed SOA formation enhancement.

关键词: manganese sulfate     zinc sulfate     seed aerosols     toluene photooxidation     secondary organic aerosol    

Influence of influent on anaerobic ammonium oxidation in an Expanded Granular Sludge Bed-Biological Aerated

Daijun ZHANG, Cui BAI, Ting TANG, Qing YANG

《环境科学与工程前沿(英文)》 2011年 第5卷 第2期   页码 291-297 doi: 10.1007/s11783-010-0270-6

摘要: Shortcut nitrification-denitrification, anaerobic ammonium oxidation (ANAMMOX), and methanogenesis have been successfully coupled in an Expanded Granular Sludge Bed-Biological Aerated Filter (EGSB-BAF) integrated system. As fed different synthetic wastewater with chemical oxygen demand (COD) of 300–1200 mg·L and of 30–120 mg·L at the outer recycle ratio of 200%, the influence of influent on ANAMMOX in the integrated system was investigated in this paper. The experimental results showed that higher COD concentration caused an increase in denitrification and methanogenesis but a decrease in ANAMMOX; however, when an influent with the low concentration of COD was used, the opposite changes could be observed. Higher influent concentration favored ANAMMOX when the COD concentration of influent was fixed. Therefore, low ratio would decrease competition for nitrite between ANAMMOX and denitrification, which was favorable for reducing the negative effect of organic COD on ANAMMOX. The good performance of the integrated system indicated that the bacterial community of denitrification, ANAMMOX, and methanogenesis could be dynamically maintained in the sludge of EGSB reactor for a certain range of influent.

关键词: Expanded Granular Sludge Bed-Biological Aerated Filter (EGSB-BAF) integrated system     the influence of influent     anaerobic ammonium oxidation (ANAMMOX)     shortcut nitrification-denitrification     methano-genesis    

The solubility of cefquinome sulfate in pure and mixed solvents

Rongbao Qi,Jingkang Wang,Junxiao Ye,Hongxun Hao,Ying Bao

《化学科学与工程前沿(英文)》 2016年 第10卷 第2期   页码 245-254 doi: 10.1007/s11705-016-1569-z

摘要: Solid-liquid equilibrium data of cefquinome sulfate is important to develop industrial crystallization processes for cefquinome sulfate. The solubilities of cefquinome sulfate in five pure solvents (methanol, ethanol, ethylene glycol, acetic acid and water) from 277.15 to 305.15 K and in a binary acetone-water solvent from 278.15 to 293.15 K were measured at atmospheric pressure. The pure-solvent solubility data was correlated to the modified Apelblat and Van’t Hoff equations whereas the mixed-solvent system data was correlated to the modified Apelblat, Van’t Hoff, CNIBS/R-K and Jouyban-Acree models. It was found that the solubilities of cefquinome sulfate in all tested solvents decreased with the increasing of temperature. In addition, the thermodynamic properties of the dissolution processes, including standard Gibbs free energy, enthalpy and entropy changes, were calculated using the Van’t Hoff equation. It was found that the dissolution of cefquinome sulfate is exothermic.

关键词: cefquinome sulfate     solubility     thermodynamic properties    

PICRUSt2 functionally predicts organic compounds degradation and sulfate reduction pathways in an acidogenic

《环境科学与工程前沿(英文)》 doi: 10.1007/s11783-021-1481-8

摘要:

For comprehensive insights into the influences of sulfate on performance, microbial community and metabolic pathways in the acidification phase of a two-phase anaerobic system, a laboratory-scale acidogenic bioreactor was continuously operated to treat wastewater with elevated sulfate concentrations from 2000 to 14000 mg/L.

关键词: Acidogenic phase reactor     High-sulfate wastewater     Sulfate reduction     Acidogenic fermentation     PICRUSt2    

Filtration ability of hollow fiber membrane for production of magnesium ammonium phosphate crystals by

H. Watamura, H. Marukawa, I. Hirasawa

《化学科学与工程前沿(英文)》 2013年 第7卷 第1期   页码 55-59 doi: 10.1007/s11705-013-1312-y

摘要: Relationship between magnesium ammonium phosphate (MAP) crystal properties and the filtration ability of hollow fiber membrane (HFM) were investigated. Phosphorus recovery process by crystallization has a problem that it produces a large amount of fine crystals. So improvement of the crystallization process by combining with filtration was discussed. MAP crystals were obtained by batch reaction crystallization and the filtration characteristics were investigated. The filtration was evaluated by the specific filtration resistance ( ) on HFM. Filtered slurry was prepared with each suspension density and crystal size distribution. The solution was filtered at constant pressure of 0.02 MPa and the filtration time on each filtrated volume was recorded. As a result, decreases exponentially with suspension density increasing from 0.25 g/L to 0.5 g/L and decreases moderately with suspension density increasing from 0.5 g/L to 1.5 g/L. of large crystals decreases exponentially at less suspension density than of small crystals does. Also, increases as the ratio of the fractured crystals increases.

关键词: membrane separation     crystallization     MAP    

Effects of metal ions on the morphology of calcium sulfate hemihydrate whiskers by hydrothermal method

Tianjie Liu, Hao Fan, Yanxia Xu, Xingfu Song, Jianguo Yu

《化学科学与工程前沿(英文)》 2017年 第11卷 第4期   页码 545-553 doi: 10.1007/s11705-017-1665-8

摘要: The effects of Na , Mg , Al and Fe ion concentrations on the crystal morphology of calcium sulfate hemihydrate whiskers formed via a hydrothermal method have been studied. In the presence of Al concentrations higher than 1×10 mol/L the whiskers were significantly shorter and thicker and the presence of Mg and Fe resulted in shorter whiskers. The presence of Na did not affect the morphology of the whiskers. Through elemental analysis, it was determined that Mg and Al were selectively adsorbed on the surfaces of the crystals, whereas Fe underwent a hydrolysis reaction to form a brown precipitate which decreased the ion concentration in the solution. These results indicate that in raw materials used for the industrial preparation of calcium sulfate whiskers, Al and Fe should be removed and the Mg concentration should be less than 8 × 10 mol/L in order to obtain pure whiskers with high aspect ratios.

关键词: metal ions     morphology     calcium sulfate hemihydrate whiskers     hydrothermal method     selective adsorption    

New insights into the formation of ammonium nitrate from a physical and chemical level perspective

《环境科学与工程前沿(英文)》 2023年 第17卷 第11期 doi: 10.1007/s11783-023-1737-6

摘要:

● Factor analysis of ammonium nitrate formation based on thermodynamic theory.

关键词: Ammonium nitrate formation     Thermodynamic theory     Aerosol liquid water content     Source apportionment    

Migration of ammonium nitrogen in ion-absorbed rare earth soils during and post mining: a column study

《环境科学与工程前沿(英文)》 2023年 第17卷 第8期 doi: 10.1007/s11783-023-1702-4

摘要:

● Column experiments with an inclined slope were applied to simulate NH4–N transport.

关键词: Ion-absorbed rare earth     Ammonium nitrogen transport     HYDRUS-2D     Numerical simulation    

on the performance and bacterial community in an expanded granular sludge bed reactor treating high-sulfate

Jun Li, Wentao Li, Gan Luo, Yan Li, Aimin Li

《环境科学与工程前沿(英文)》 2019年 第13卷 第1期 doi: 10.1007/s11783-019-1090-y

摘要:

Less than 50 mg/L nitrobenzene brought little effect on anaerobic sulfate reduction.

Kinetics of sulfate reduction under different nitrobenzene contents was studied.

Increased nitrobenzene contents greatly changed the bacterial community structure.

Genus Desulfovibrio played the key role in anaerobic sulfate reduction process.

关键词: Nitrobenzene (NB)     Sulfate-reducing bacteria (SRB)     Bacterial community     Sulfate reduction     High-throughput sequencing    

Enabling nickel ferrocyanide nanoparticles for high-performance ammonium ion storage

《化学科学与工程前沿(英文)》 2023年 第17卷 第2期   页码 226-235 doi: 10.1007/s11705-022-2198-3

摘要: Prussian blue and its analogs are extensively investigated as a cathode for ammonium-ion batteries. However, they often suffer from poor electronic conductivity. Here, we report a Ni2Fe(CN)6/multiwalled carbon nanotube composite electrode material, which is prepared using a simple coprecipitation approach. The obtained material consists of nanoparticles with sizes 30–50 nm and the multiwalled carbon nanotube embedded in it. The existence of multiwalled carbon nanotube ensures that the Ni2Fe(CN)6/multiwalled carbon nanotube composite shows excellent electrochemical performance, achieving a discharge capacity of 55.1 mAh·g–1 at 1 C and 43.2 mAh·g–1 even at 15 C. An increase in the ammonium-ion diffusion coefficient and ionic/electron conductivity based on kinetic investigations accounts for their high performance. Furthermore, detailed ex situ characterizations demonstrate that Ni2Fe(CN)6/multiwalled carbon nanotube composite offers three advantages: negligible lattice expansion during cycling, stable structure, and the reversible redox couple. Therefore, the Ni2Fe(CN)6/multiwalled carbon nanotube composite presents a long cycling life and high rate capacity. Finally, our study reports a desirable material for ammonium-ion batteries and provides a practical approach for improving the electrochemical performance of Prussian blue and its analogs.

关键词: nickel ferrocyanides     NH4+     electrochemistry     Prussian blue     aqueous ammonium ion batteries    

标题 作者 时间 类型 操作

Biological conversion pathways of sulfate reduction ammonium oxidation in anammox consortia

Zhen Bi, Deqing Wanyan, Xiang Li, Yong Huang

期刊论文

Thermal decomposition mechanism of ammonium sulfate catalyzed by ferric oxide

Xingfu SONG, Jingcai ZHAO, Yunzhao LI, Ze SUN, Jianguo YU

期刊论文

Effects of SO

Quanming Liang, Jian Li, Hong He, Wenjun Liang, Tiejun Zhang, Xing Fan

期刊论文

Effects of natural zeolite and sulfate ions on the mechanical properties and microstructure of plastic

期刊论文

A time−space porosity computational model for concrete under sulfate attack

期刊论文

Effects of two transition metal sulfate salts on secondary organic aerosol formation in toluene/NO

Biwu CHU, Jiming HAO, Junhua LI, Hideto TAKEKAWA, Kun WANG, Jingkun JIANG

期刊论文

Influence of influent on anaerobic ammonium oxidation in an Expanded Granular Sludge Bed-Biological Aerated

Daijun ZHANG, Cui BAI, Ting TANG, Qing YANG

期刊论文

The solubility of cefquinome sulfate in pure and mixed solvents

Rongbao Qi,Jingkang Wang,Junxiao Ye,Hongxun Hao,Ying Bao

期刊论文

PICRUSt2 functionally predicts organic compounds degradation and sulfate reduction pathways in an acidogenic

期刊论文

Filtration ability of hollow fiber membrane for production of magnesium ammonium phosphate crystals by

H. Watamura, H. Marukawa, I. Hirasawa

期刊论文

Effects of metal ions on the morphology of calcium sulfate hemihydrate whiskers by hydrothermal method

Tianjie Liu, Hao Fan, Yanxia Xu, Xingfu Song, Jianguo Yu

期刊论文

New insights into the formation of ammonium nitrate from a physical and chemical level perspective

期刊论文

Migration of ammonium nitrogen in ion-absorbed rare earth soils during and post mining: a column study

期刊论文

on the performance and bacterial community in an expanded granular sludge bed reactor treating high-sulfate

Jun Li, Wentao Li, Gan Luo, Yan Li, Aimin Li

期刊论文

Enabling nickel ferrocyanide nanoparticles for high-performance ammonium ion storage

期刊论文