N-containing Organic Compounds Research Articles

Electrochemical degradation of acetaminophen in urine matrices: Unraveling complexity and implications for realistic treatment strategies

Urine has an intricate composition with high concentrations of organic compounds like urea, creatinine, and uric acid. Urine poses a formidable challenge for advanced effluent treatment processes following urine diversion strategies. Urine matrix complexity is heightened when dealing with pharmaceutical residues like acetaminophen (ACT) and metabolized pharmaceuticals. This work explores ACT degradation in synthetic, fresh real, and hydrolyzed real urines using electrochemical oxidation with a dimensional stable anode (DSA). Analyzing drug concentration (2.5 - 40 mg L−1) over 180 min at various current densities in fresh synthetic effluent revealed a noteworthy 75% removal at 48 mA cm−2. ACT degradation kinetics and that of the other organic components followed a pseudo-first-order reaction. Uric acid degradation competed with ACT degradation, whereas urea and creatinine possessed higher oxidation resistance. Fresh real urine presented the most challenging scenario for the electrochemical process. Whereas, hydrolyzed real urine achieved higher ACT removal than fresh synthetic urine. Carboxylic acids like acetic, tartaric, maleic, and oxalic were detected as main by-products. Inorganic ionic species nitrate, nitrite, and ammonium ions were released to the medium from N-containing organic compounds. These findings underscore the importance of considering urine composition complexities and provide significant advancements in strategies for efficiently addressing trace pharmaceutical contamination.

Unraveling roles of dissolved organic matter in the co-occurrence of arsenic and ammonium in Quaternary alluvial-lacustrine aquifers

Geogenic arsenic (As) and ammonium (NH4+)-contaminated groundwaters are global public concerns, posing threats to human health and ecological security. However, when considering the enrichment of either As or NH4+ in groundwater, the concurrent occurrence of both contaminants warrants further discussion. Herein, we conducted a hydrogeochemical study in the shallow confined aquifer of the central Yangtze River basin to elucidate the key mechanism of coexistence of As and NH4+ through a thorough analysis of groundwater chemistry, inorganic carbon isotope (δ13C-DIC), and dissolved organic matter (DOM). High As and NH4+ groundwater mainly occurs in meanders of the middle reaches of Yangtze River, with maximum concentrations up to 936 μg/L and 45.3 mg/L, respectively. Our findings indicate that the degradation levels and characteristics of DOM play a significant role in the co-occurrence of As and NH4+ with varying concentrations in groundwater. δ13C-DIC signatures show that there was a simultaneous increase in the concentrations of As and NH4+ in groundwater, with the highest concentration of As during fermentative conditions. In contrast, during the progression of OM degradation towards methanogenesis, the NH4+ concentration reached its peak, while the As concentration was lower compared to the fermentation stage. Optical properties of DOM demonstrate that elevated levels of NH4+ result from the mineralization of N-containing organic compounds particularly as the degradation proceeds to methanogenesis stage, while both fermentation and methanogenesis processes significantly contribute to the microbially reductive dissolution of As-bearing iron oxides in groundwater systems. This study presents isotopic and fluorescent evidence to clarify the co-existence of As and NH4+ in Quaternary alluvial-lacustrine aquifers.

A study on the structures and primary reaction products of kerogens in Longkou oil shale with different densities through supercritical ethanolysis

The difference in the density of oil shale significantly affects the structural characteristics of the kerogen, which brings the change in the pyrolysis behavior, thus leading to different retorting oil yields. The primary reaction (the cleavage of weak covalent bonds into free radicals) in the pyrolysis of oil shale greatly affects the retorting oil yield and quality. In this work, the structural characteristics and primary reaction products of the kerogens in Longkou oil shale (LKOS) with three different densities (<1.3, 1.4 − 1.5, 1.8 − 1.9 g/cm3) were investigated by supercritical ethanolysis, 13C nuclear magnetic resonance (13C NMR) and Fourier transform infrared spectroscopy (FTIR). The weak covalent bonds in the kerogens were broken by ethanolysis at 350 °C to obtain small molecular substances (SMSs) with the carbon conversions of 28 %, 47 % and 54 %, respectively. The SMSs can be divided into aliphatic acid esters, aromatics, alkanes and N-containing organic compounds (NCCs). Among the SMSs, the relative contents of the aliphatic acid esters, whose aliphatic chain lengths distribute in C3-C23, C1-C24 and C1-C28, are the highest. The aromatics are mainly monocyclic, and the NCCs mainly exist as amines. The possible pathways for these ethanolysis products were proposed. The 13C NMR and FTIR analyses of the kerogens and their ethanolysis residues show that the aliphaticity (fal) and average methylene chain length (Cn) increase, while the aromaticity (fa) and average aromatic cluster size (Xb) decrease with the increasing oil shale density. After ethanolysis, the value of fa gradually increases, while that of fal and Cn decrease. Furthermore, the contents of C=O and O-C=O decrease, while that of O-C-O and C-OH increase. The results suggest that the SMSs are connected to the kerogen matrix by weak covalent bonds. The cleavage of C=O, O-C=O and C-O bonds dominates the early stage of the oil shale pyrolysis. During the pyrolysis of oil shale, these weak covalent bonds are first broken and the above SMSs are the most primary reaction products and then undergo the second reactions to yield oil and gas.

Enhancing characterization of organic nitrogen components in aerosols and droplets using high-resolution aerosol mass spectrometry

Abstract. This study aims to enhance the understanding and application of the Aerodyne high-resolution aerosol mass spectrometer (HR-AMS) for the comprehensive characterization of organic nitrogen (ON) compounds in aerosol particles and atmospheric droplets. To achieve this goal, we analyzed 75 N-containing organic compounds, representing a diverse range of ambient non-organonitrate ON (NOON) types, including amines, amides, amino acids, N heterocycles, protein, and humic acids. Our results show that NOON compounds can produce significant levels of NHx+ and NOx+ ion fragments, which are typically recognized as ions representative of inorganic nitrogen species. We also identified the presence of CH2N+ at m/z = 28.0187, an ion fragment rarely quantified in ambient datasets due to substantial interference from N2+. As a result, the utilization of an updated calibration factor of 0.79 is necessary for accurate NOON quantification via the HR-AMS. We also assessed the relative ionization efficiencies (RIEs) for various NOON species and found that the average RIE for NOON compounds (1.52 ± 0.58) aligns with the commonly used default value of 1.40 for organic aerosol. Moreover, through a careful examination of the HR-AMS mass spectral features of various NOON types, we propose fingerprint ion series that can aid the NOON speciation analysis. For instance, the presence of CnH2n+2N+ ions is closely linked with amines, with CH4N+ indicating primary amines, C2H6N+ suggesting secondary amines, and C3H8N+ representing tertiary amines. CnH2nNO+ ions (especially for n values of 1–4) are very likely derived from amides. The co-existence of three ions, C2H4NO2+, C2H3NO+, and CH4NO+, serves as an indicator for the presence of amino acids. Additionally, the presence of CxHyN2+ ions indicates the occurrence of 2N-heterocyclic compounds. Notably, an elevated abundance of NH4+ is a distinct signature for amines and amino acids, as inorganic ammonium salts produce only negligible amounts of NH4+ in the HR-AMS. Finally, we quantified the NOON contents in submicron particles (PM1) and fog water in Fresno, California, and PM1 in New York City (NYC). Our results revealed the substantial presence of amino compounds in both Fresno and NYC aerosols, whereas concurrently collected fog water in Fresno contained a broader range of NOON species, including N-containing aromatic heterocycle (e.g., imidazoles) and amides. These findings highlight the significant potential of employing the widespread HR-AMS measurements of ambient aerosols and droplets to enhance our understanding of the sources, transformation processes, and environmental impacts associated with NOON compounds in the atmosphere.

N-methyl pyrrolidone manufacturing wastewater as the electron donor for denitrification: From bench to pilot scale

Actual wastewater generated from N-methylpyrrolidone (NMP) manufacture was used as electron donor for tertiary denitrification. The organic components of NMP wastewater were mainly NMP and monomethylamine (CH3NH2), and their biodegradation released ammonium that was nitrified to nitrate that also had to be denitrified. Bench-scale experiments documented that alternating denitrification and nitrification realized effective total‑nitrogen removal. Ammonium released from NMP was nitrified in the aerobic reactor and then denitrified when actual NMP wastewater was used as the electron donor for endogenous and exogenous nitrate. Whereas TN and NMP removals occurred in the denitrification step, dissolved organic carbon (DOC) and CH3NH2 removals occurred in the denitrification and nitrification stages. The genera Thauera and Paracoccus were important for NMP biodegradation and denitrification in the denitrification reactor; in the nitrification stage, Amaricoccus and Sphingobium played key roles for biodegrading intermediates of NMP, while Nitrospira was responsible for NH4+ oxidation to NO3−. Pilot-scale demonstration was achieved in a two-stage vertical baffled bioreactor (VBBR) in which total‑nitrogen removal was realized sequential anoxic-oxic treatment without biomass recycle. Although the bench-scale reactors and the VBBR had different configurations, both effectively removed total nitrogen through the same mechanisms. Thus, an N-containing organic compound in an industrial wastewater could be used to drive total-N removal in a tertiary-treatment scenario.

Pollutant Emissions from Municipal Biowaste Composting: Comparative Analysis and Contribution of N-Containing Organic Compounds

The disposal of municipal biowaste is associated with the formation of malodorous and frequently hazardous volatile compounds. The composition of volatile pollutants formed during composting of mechanically sorted organic fraction of municipal solid waste (ms-OFMSW), sewage sludge (SS), food waste (FW), and wood waste (WC) during 28 days in a laboratory setup was analysed using electrochemical measurements, gas chromatography, and solid phase microextraction. Despite the close biodegradation intensity of SS+WC, ms-OFMSW, and FW+WC, the average temperature values were 57.0, 51.7, and 50.6 °C. The emission of volatile substances per day were: CO2 0.64, 0.68, and 0.64 g/kg, NH3 22.3, 93.1, and 4.9 µg/kg, CH4 5.3, 1.5 and 8.7 mg/kg, H2S 5.0, 3.3 and 1.8 µg/kg organic matter. The ratios of emission from SS+FW, ms-OFMSW and FW+WC for inorganic substances were 1.0, 1.1, and 1.0, and for organic compounds (VOC) were 1, 24, and 123. A total of 121 VOC was identified. The 12 N-containing compounds detected at the beginning of composting, some of which are highly toxic, ranged from 3.2 to 21.0% of the total VOC and belonged to amines with a very low olfactory thresholds and heterocyclic compounds. The results of this research help to optimise the systems used to remove pollutants from exhaust air.

Formation of nitrogen-containing gas phase products from the heterogeneous (photo)reaction of NO2 with gallic acid

Heterogeneous reaction of gas phase NO2 with atmospheric humic-like substances (HULIS) is potentially an important source of volatile organic compounds (VOCs) including nitrogen (N)-containing compounds, a class of brown carbon of emerging importance. However, the role of ubiquitous water-soluble aerosol components in this multiphase chemistry, namely nitrate and iron ions, remains largely unexplored. Here, we used secondary electrospray ionization ultrahigh-resolution mass spectrometry for real-time measurements of VOCs formed during the heterogeneous reaction of gas phase NO2 with a solution containing gallic acid (GA) as a proxy of HULIS at pH 5 relevant for moderately acidic aerosol particles. Results showed that the number of detected N-containing organic compounds largely increased from 4 during the NO2 reaction with GA in the absence of nitrate and iron ions to 55 in the presence of nitrate and iron ions. The N-containing compounds have reduced nitrogen functional groups, namely amines, imines and imides. These results suggest that the number of N-containing compounds is significantly higher in deliquescent aerosol particles due to the influence of relatively higher ionic strength from nitrate ions and complexation/redox reactivity of iron cations compared to that in the dilute aqueous phase representative of cloud, fog, and rain water.

Influence of temperature on the heterogeneous reaction of toluene to N-containing organic compounds using in situ DRIFTS

Heterogeneous reactions of toluene/NO2 with and without O3 on α-Fe2O3 particles was studied as a function of temperature by using in situ diffuse reflectance infrared Fourier transform spectrometry (DRIFTS). The results show that the formation of R-ONO2 group is identified on the α-Fe2O3 particles surface, indicating the formation of benzyl nitrate in the presence of toluene/NO2 with or without O3 at different temperatures from 253 K to 298 K. From the analysis of the spectral changes, the reaction kinetics, such as reaction rate and uptake coefficient are sensitive to temperature. During the heterogeneous reaction of toluene/NO2, the formation rate of organic nitrate increases from (2.38 ± 0.07) × 1017 ions g−1 s−1 to (5.95 ± 0.09) × 1017 ions g−1 s−1 when the temperature decreases from 278 K to 253 K. When the trace gases were toluene/NO2/O3, the reaction rate increases about 3 folds with the increasing of temperature from 253 K to 298 K. In the absence of ozone, nitrification from heterogeneous reaction is exothermic process. However, the addition of ozone dominates the whole reaction process, resulting the different change trends of formation rate at similar range of temperatures. Furthermore, reactive uptake coefficient increases from (6.73 ± 0.02) × 10−7 to (1.64 ± 0.05) × 10−6 with decreasing temperature from 278 K to 253 K during the heterogeneous reaction of toluene/NO2 on α-Fe2O3 particles. The values of activation energy for the heterogeneous reaction of toluene/NO2 and toluene/NO2/O3 are determined to be −8.60 ± 0.91 kJ mol−1 and 15.14 ± 2.51 kJ mol−1, respectively. It implies that the heat change is an important factor in affecting the heterogeneous reaction under the seasonal temperature changes.

Systematic Characterization of the Chemical Components of Canna edulis Ker-Gawl Based on UHPLC Q-Exactive Orbitrap MS Technology

Canna edulis Ker-Gawl is a versatile crop that integrates food, energy, and feed in China. The rhizome is a traditional Chinese medicine with a long history. However, there are few studies on chemical components. Crude plant extracts are a complex mixture of several biologically active secondary metabolites. Therefore, rapid and accurate identification and quantification are critical in phytochemical analysis. An efficient approach based on ultrahigh-performance liquid chromatography coupled with Q-Exactive Orbitrap tandem mass spectrometry (UHPLC Q-Exactive Orbitrap MS) was used to analyze the chemical components systematically. We used retention time, accurate molecular weight, parent peaks, fragment peaks, fragmentation characteristics, comparative analysis with the literature, reference standards, and standard databases, including ChemSpider, mzVault, MassBank, and mzCloud. A total of 54 chemical constituents were identified from the methanol extract of the rhizome, including 36 organic acids (with six phenolic acids), three phenols, one sugar (and its derivatives), one coumarin, one triterpenoid, ten N-containing organic compounds (including seven amino acids), and two other compounds. Moreover, three compounds were quantitatively analyzed and a methodological study of the three components was carried out. The established method provided satisfactory precision and accuracy, acceptable recovery, good linearity, and a reasonable detection limit. The UHPLC Q-Exactive Orbitrap MS method was used for the first time to accurately, quickly, and systematically characterize the compounds of the rhizome, revealing the pharmacodynamic substances and providing a theoretical basis for its quality control, in-depth research, and development.

From Dinitrogen to N-Containing Organic Compounds: Using Li2CN2 as a Synthon.

By synergizing the heterogeneous synthetic approach with the homogeneous synthetic methodology, N-containing organic compounds can be synthesized via activated N-containing species prepared from N2 gas and suitable carbon sources. From N2, carbon, and LiH, we have previously succeeded in the high-yield preparation of Li2CN2 as the activated N-containing species. In this work, we applied Li2CN2 as a novel synthetic synthon for constructing N-containing organic compounds. A series of reaction models, including substitution reaction, cycloaddition reaction, and transition metal-catalyzed coupling reaction, were successfully performed using Li2CN2 under mild conditions. Various valuable cyanamides, carbodiimides, N-aryl cyanamides and 1,2,4-triazole derivatives were readily synthesized in moderate to excellent yields. With this method, the 15N-labeled products, including oxazolidine derivatives with anti-cancer activity, could also be facilely prepared from 15N2 gas.

Release and evolution mechanism of oxygen-containing compounds and aromatics during the co-pyrolysis of waste tire and bamboo sawdust/rice husk by Py-GC/MS

Using the measurement technique pyrolysis gas-chromatography/mass spectrometry, the release characteristics of oxygen-containing compounds and aromatics during the pyrolysis of waste tire (WT) and the co-pyrolysis of WT and bamboo sawdust (BS)/rice hull (RH) were analyzed at low temperature (350 °C), medium temperature (550 °C) and high temperature (750 °C). The oxygen-containing compounds from the WT pyrolysis contained acids, phenols, alcohols, esters, peroxides and oxygen-containing heterocycles. Especially, the acids such as palmitic acid and stearic acid presented the highest proportion of 8.68% at 350 °C. The oxygen-containing compounds proportion showed a sharply decreasing trend with the increase of temperature. The aromatics proportion was extremely low at 350 °C and 550 °C, while aromatics proportion was as high as 44.64%, including benzene, alkyl substituted benzene, indene, naphthalene and alkyl substituted naphthalene at 750 °C. The proportion of benzene, toluene and xylene was 17.05%, and that of naphthalene and its derivatives was 7.86%. After adding BS or RH, the aromatics proportion increased at 550 °C. The aromatics proportion decreased by more than 16% with the addition of BS, while the aromatics proportion increased with the addition of RH, such as benzene, indene and naphthalene derivatives. It was also found that the relative oxygen-containing components and aromatics proportion showed an opposite trend along the temperature. At 750 °C, oxygen-containing compounds could be converted into aromatics through a series of free radical reactions. For the WT pyrolysis, N-containing organic compounds proportion in gas product as the temperature increased. While the S-containing organic compounds were released into gas phase only at 550 °C. Adding BS could reduce the formation of N- and S- containing organic compounds. However, adding RH inhabited the N-containing organic compounds formation only at 350 °C. Adding RH also inhabited the formation of S-containing organic compounds formation, while this while this positive effect was weaker than that of adding BS. Finally, according to the obtained results from Py-GC/MS at different temperatures, it was found that the active oxygen-containing free radicals released from BS could promote the chain breaking of rubber components and release hydrogen free radicals. With the aggravation of hydrogen transfer reaction, the oxygen-containing organic compounds were continuously transformed into hydrocarbon products. Co-pyrolysis promoted decarboxylation and decarbonylation reaction, resulting in the formation of H2 and free radicals, thus promoting the generation of alicyclic hydrocarbons, aliphatic chain hydrocarbons and benzene. This work provided the in-depth comparison and investigation the waste tire pyrolysis and products evolution.

Mechanism of Nitrogen-Carbon Bond Formation from Iron(IV) Disilylhydrazido Intermediates during N2 Reduction.

We recently reported a reaction sequence that activates C-H bonds in simple arenes as well as the N-N triple bond in N2, delivering the aryl group to N2 to form a new N-C bond (Nature 2020, 584, 221). This enables the transformation of abundant feedstocks (arenes and N2) into N-containing organic compounds. The key N-C bond forming step occurs upon partial silylation of N2. However, the pathway through which reduction, silylation, and migration occurred was unknown. Here, we describe synthetic, structural, magnetic, spectroscopic, kinetic, and computational studies that elucidate the steps of this transformation. N2 must be silylated twice at the distal N atom before aryl migration can occur, and sequential silyl radical and silyl cation addition is a kinetically competent pathway to a formally iron(IV)-NN(SiMe3)2 intermediate that can be isolated at low temperature. Kinetic studies show its first-order conversion to the migrated product, and DFT calculations indicate a concerted transition state for migration. The electronic structure of the formally iron(IV) intermediate is examined using DFT and CASSCF calculations, which reveal contributions from iron(II) and iron(III) resonance forms with oxidized NNSi2 ligands. The depletion of electron density from the Fe-coordinated N atom makes it electrophilic enough to accept the incoming aryl group. This new pathway for the N-C bond formation offers a method for functionalizing N2 using organometallic chemistry.

High-capacity proton battery based on π-conjugated N-containing organic compound

Aqueous proton batteries (APBs) have tremendous potential in the energy storage field. Currently, high-performance electrode materials need to be urgently exploited to satisfy the development of APBs. Here, we introduce a π-conjugated N-containing organic compound (diquinoxalino [2,3-a:2’,3’-c] phenazine, HATN) with abundant active sites as the anode. By assembling HATN with a β-MnO2 cathode, we produce a high-capacity proton battery with a reversible specific capacity of 260 mAh g−1 at 0.1 A g−1 and an excellent energy density up to 118 Wh kg−1. The high performance is found to result from the abundant C=N moieties and the π-conjugated structure of HATN, which assure the capability of reversible H+ storage and the corresponding stability.

Physical and chemical characterization of urban grime: An impact on the NO2 uptake coefficients and N-containing product compounds.

Urban grime represents an important environmental surface for heterogeneous reactions in urban environment. Here, we assess the physical and chemical properties of urban grime collected during six consecutive months in downtown of Guangzhou, China. There is a significant variation of the uptake coefficients of NO2 on the urban grime as a function of the relative humidity (RH). In absence of water molecules (0% RH), the light-induced uptake coefficients of NO2 on urban grime samples collected during six months are very similar in order of ≈10-6. At 80% RH, depending on the sampling month the light-induced uptake coefficient of NO2 can reach one order of magnitude higher values (1.5 × 10-5, at 80% RH) compared to those uptakes at 0% RH. In presence of 80% RH, there are strong correlations between the measured NO2 uptakes and the concentrations of the water soluble carbon, soluble anions, polycyclic aromatic hydrocarbons and n-alkanes depicted in the urban grime. These correlations, demonstrate that surface adsorbed water on urban grime play an important role for the uptakes of NO2. The heterogeneous conversion of NO2 on two-month old urban grime under sunlight irradiation (68 W m-2, 300 nm < λ < 400 nm) at 60% RH leads to the formation of unprecedented HONO surface flux of 4.7 × 1010 molecules cm-2 s-1 which is higher than all previously observed HONO fluxes, thereby affecting the oxidation capacity of the urban atmosphere. During the heterogeneous chemistry of NO2 with urban grime, the unsaturated and N-containing organic compounds are released in the gas phase which can affect the air quality in the urban environment.

(n-Bu)4NBr-Promoted N2 Splitting to Molybdenum Nitride.

Splitting of N2 via six-electron reduction and further functionalization to value-added products is one of the most important and challenging chemical transformations in N2 fixation. However, most N2 splitting approaches rely on strong chemical or electrochemical reduction to generate highly reactive metal species to bind and activate N2, which is often incompatible with functionalizing agents. Catalytic and sustainable N2 splitting to produce metal nitrides under mild conditions may create efficient and straightforward methods for N-containing organic compounds. Herein, we present that a readily available and nonredox (n-Bu)4NBr can promote N2-splitting with a Mo(III) platform. Both experimental and theoretical mechanistic studies suggest that simple X- (X = Br, Cl, etc.) anions could induce the disproportionation of MoIII[N(TMS)Ar]3 at the early stage of the catalysis to generate a catalytically active {MoII[N(TMS)Ar]3}- species. The quintet MoII species prove to be more favorable for N2 fixation kinetically and thermodynamically, compared with the quartet MoIII counterpart. Especially, computational studies reveal a distinct heterovalent {MoII-N2-MoIII} dimeric intermediate for the N≡N triple bond cleavage.

Investigation of Plasma Induced Reactions of Liquid Toluene in Ar/NH3: the Formation of Organic Compounds through Radical Intermediates

Abstract The treatment of liquid toluene in Ar/NH3 plasma generated by a dielectric barrier discharge (DBD) at ambient temperature and atmospheric pressure was studied. N-containing organic compounds and toluene-derived hydrocarbons were detected by gas chromatography-mass spectrometry analysis (GC-MS) after plasma treatment. Oxygenated organic compounds were also found due to the presence of residual oxygen in this plasma system.

Carbon balance analysis of sewage sludge biochar-to-soil system

Converting sewage sludge (SS) into biochar via pyrolysis is proposed as a prospective strategy for recycling nutrients and reducing environmental risks. Yet, from the perspective of carbon (C) balance the viability of pyrolyzing SS still remains unclear. Here we quantified the C footprint of the whole process from raw SS pyrolysis to final disposal of SS-derived biochar (SSB) using life cycle assessment based on a 20-tonne industrial pyrolysis furnace and field experiments. Results indicated that about 0.101 tonnes of direct CO2 equivalent (CO2e) (from N-containing organic compounds in SS) plus 1.506 tonnes of indirect CO2e (from energy consumption and dewatering agents) were emitted for each tonne of dry SS treated during its dewatering and pyrolysis processes, and at least 0.252 tonnes of CO2e were sequestered as stable C in SSB, depending on the final application route of SSB. In contrast, the net C emissions from traditional SS treatments amounted to at least 2.432 tonnes of CO2e per tonne of dry SS under the similar scenarios. Converting SS into SSB thus showed great advantages in C balance over the traditional treatments of SS. Sensitivity analyses indicated that the moisture and C contents of SS and the usage of dewatering agents were the key factors affecting C balance in the SSB-to-soil system. These findings highlight the C sequestration potential of pyrolysis and provide important support for the optimization and management of SS treatment.

Aqueous zinc batteries using N-containing organic cathodes with Zn2+ and H+ Co-uptake

Aqueous zinc batteries are considered as one of the most promising energy storage systems for large-scale energy storage and wearable electronics, owing to their low cost and intrinsic safety. However, developing high-performance cathode materials with environmentally friendly is still an important task. Here, we demonstrate that two N-containing organic compounds, hexamethoxy hexaazatrinaphthylene (HMHATN) and hexaazatrinaphthylene (HATN), used as cathodes can exhibit high capacity with fast kinetics. Thus, the Zn//HMHATN and Zn//HATN full batteries display the high energy density of 160 and 221.6 W h Kg−1, respectively, and long-term cycling stability. Electrochemical analysis, density functional theory calculation and ex situ analysis identify that the organic cathodes involve uptake and removal of Zn2+ and H+ in the discharging-charging process. Furthermore, the flexible aqueous Zn//HMHATN and Zn//HATN batteries fabricated also have high capacity, long-term cycling life and impressive energy density, displaying its application prospect in wearable electronics.

High-Capacity Proton Battery Based on Π-Conjugated N-Containing Organic Compound

High-Capacity Proton Battery Based on Π-Conjugated N-Containing Organic Compound

Molecular Characterization of Nitrogen-Containing Compounds in Humic-like Substances Emitted from Biomass Burning and Coal Combustion.

N-containing organic compounds (NOCs) in humic-like substances (HULIS) emitted from biomass burning (BB) and coal combustion (CC) were characterized by ultrahigh-resolution mass spectrometry in the positive electrospray ionization mode. Our results indicate that NOCs include CHON+ and CHN+ groups, which are detected as a substantial fraction in both BB- and CC-derived HULIS, and suggest that not only BB but also CC is the potential important source of NOCs in the atmosphere. The CHON+ compounds mainly consist of reduced nitrogen compounds with other oxygenated functional groups, and straw- and coal-smoke HULIS exhibit a lower degree of oxidation than pine-smoke HULIS. In addition, the NOCs with higher N atoms (N2 and/or N3) generally bear higher modified aromaticity index (AImod) values and are mainly contained in BB HULIS, especially in straw-smoke HULIS, whereas the NOCs with a lower N atom (N1) always have relatively lower AImod values and are the dominant NOCs in CC HULIS. These findings imply that the primary emission from CC may be a significant source of N1 compounds, whereas high N number (e.g., N2-3) compounds could be associated with burning of biomass materials. Further study is warranted to distinguish the NOCs from more sources.