Abstract:Nitrobenzene compounds widely exist in the explosives， petrochemical， dye and other industries， and a large amount of nitrobenzene wastewater are produced in the production process， which is of great concern to scientists because of its stable structure， high toxicity and poor biodegradability. Traditional wastewater treatment methods have limited mass transfer and low treatment efficiency， and the enhanced treatment of nitrobenzene wastewater using high gravity technology has become a new and promising method. In this paper， the research progress in the treatment of nitrobenzene wastewater by high gravity enhanced physical method， reduction method and advanced ozone oxidation method is reviewed， including enhancing mass transfer process， material preparation， catalytic degradation and so on， and the key issues of scale-up process and future development for improving structure and extending the liquid residence time for high gravity enhanced treatment of nitrobenzene wastewater that should be concerned are discussed and prospected.

Abstract:Nitrobenzene， nitrotoluene and dinitrophenol in aromatic nitro compounds are the main components of explosives. In addition to their own explosiveness and danger， they also have high stability and high toxicity， which can cause great harm to human health， soil， water source and ecological environment. In this paper， the current status of aromatic nitro compound wastewater treatment technology is summarized. Based on three treatment methods of physical treatment， chemical treatment and biodegradation， the advantages and disadvantages of various technologies are summarized， and the development trend is prospected. Among the three treatment methods， the physical treatment method has potential secondary pollution risks， and the biodegradation method has higher time cost， therefore， it is considered that the chemical treatment method is considered to be the most promising method. Among them， the photocatalytic method can efficiently degrade aromatic nitro compounds wastewater only with the help of sunlight， which has the advantages of green environmental protection and energy saving. Although this method has not been applied to practical applications， other treatment technologies can be combined with photocatalytic methods to achieve the effect of complementing each other.

Abstract:Explosive TNT is the most important weapon energy source in military activities. It not only has a powerful damaging effect， but also has chemical toxicity. Even a trace amount of TNT will pose a serious threat to the natural environment and human health. Therefore， the development of trace explosive detection technology with high sensitivity， high accuracy and fast response has far-reaching research significance for protecting the ecological environment and maintaining human health. Among many trace detection technologies， biosensing technology has the advantages of good selectivity， simple synthesis， fast response and high sensitivity， and has good application prospects. This paper reviews the research progress of biosensor technology in the detection of trace explosives in recent years， focusing on the advantages and limitations of five types of biosensors： antibody immunity， peptides， aptamers， enzymes and multi-parameter loading. Among them， the sensor prepared based on aptamer has good affinity and specificity for explosive molecules， the detection limit is 1000 times lower than other types of sensors， and has good stability， easy modification and modification， and strong structural expansion ability. Future research will focus on the construction of high-throughput trace explosives sensing systems based on bioreceptor components such as aptamers， combined with neural network algorithms and machine learning to construct biosensors with multiple detection and bionic remote sensing properties.

Abstract:This review summarized progress of 2，4，6-trinitrotoluene （TNT） multifarious reutilization in the aspects of chemical transformation and microorganism degradation. Chemical transformation pathways are classified into TNT methyl oxidation， nitro reduction， and substitution reaction. The diverse chemical transformation pathways were systematically summarized according to the green environmental protection， reaction mechanism， reaction efficiency and product properties combined with resource reuse. The microorganism transformation pathways are classified into aerobic bacteria， anaerobic bacteria and fungus. A more comprehensive overview of the aerobic and anaerobic metabolic pathways of TNT microorganisms is presented， summarizing the relevant microorganisms. Finally， the development direction of waste TNT resourceful reuse based on chemical and biological transformation is prospected. Chemical transformation of TNT will go beyond the laboratory research stage， and green process research and safety will be the focus of this stage of research. Microbial transformation of TNT remains the focus of research， and combined with genetic engineering and modern molecular biology technology， it is expected to provide new solutions for deep reuse of waste TNT.

Abstract:A method of determination of hydrazine， monomethylhydrazine （MMH）， and unsymmetrical dimethylhydrazine （UDMH） in water by hydrophilic interaction chromatography （HILIC） coupled with mass spectrometry （MS） was developed. Sample preparation， composition of mobile phase and parameters of MS detection were investigated for optimization for HILIC-MS analysis of hydrazine compounds. 80% isopropanol-0.1% formic acid was used as sample solvent， and injection volume was 10 μL. Composition of mobile phase was 70% acetonitrile-10 mmol·L^-1 ammonium formate， pH=3.5. Hydrophilic interaction chromatographic column was utilized for separation. Protonated non-covalent adduct of hydrazine and acetonitrile， protonated MMH and protonated UDMH were selected as detection ions， and post-source collision energy were 50， 100， 100 eV， respectively. Good linearity between MS response intensity and analyte concentration for quantitative analysis was obtained in certain range of analyte concentration. The limits of detection for hydrazine， MMH and UDMH were 0.04， 0.005， 0.025 mg·L^-1， respectively. Recovery of spiked water sample was determined as 92%-115%.

Abstract:Due to the actual application requirement for Unsymmetrical Dimethylhydrazine（UDMH） degradation， low temperature plasma（LTP） was employed as an efficient proposal. An application device based on dielectric barrier discharge（DBD） was designed and developed with microsecond pulse power supply and six coaxial reaction tubes as the key components to generate LTP for UDMH degradation. The effects on the discharge power and power factor of power parameters were explored under different frequencies and pulse widths. Under optimal conditions， the removal efficiency of UDMH and the energy consumption were analyzed. The power factor of the experimental device increases with the increase of frequency， and has a maximum value between 2 μs and 10 μs， which is near 6 μs. The optimal parameters for power supply is the input voltage of 200 V， frequency of 1000 Hz and pulse width of 6 ms. The removal efficiency of 43.5 and 264.5 mg·L^-1 UDMH reached 99.9% and 93.8%， and the energy consumption was 0.51 and 0.18 kWh·g^-1. Therefore， the coaxial reaction tube with quartz glass and water film as barrier medium and air as the working gas can generate large-area LTP through DBD， which can degrade UDMH efficiently with low energy consumption， indicating that LTP technology has good practical value for UDMH wastewater treatment.

Abstract:The production and processing of pyrotechnics produce aniline wastewater， which causes a great pollution to the environment. To provide an efficient strain resource for aniline degradation， a strain Q6 with aniline as the only carbon source and energy growth was isolated from the activated sludge in the aerobic aeration tank of the chemical wastewater treatment plant. Through morphological observation， physiological and biochemical characteristics and 16S rDNA gene sequence phylogeny analysis， the strain was identified as Acidovorax sp. The effects of inoculum amount， temperature， pH value and additional carbon and nitrogen sources on aniline degradation by strain Q6 were studied. Meanwhile， the degradation kinetics of aniline at different initial concentrations and the growth kinetics of strain Q6 were fitted. The results showed that under the conditions of temperature 23-37 ℃ and pH 5-8， strain Q6 could degrade aniline efficiently， and ammonium chloride was the best co-metabolizing nitrogen source to promote the degradation of aniline.The optimum conditions of 33 ℃， pH 7 and inoculation amount of 10%， the degradation rate of aniline at different initial concentrations （200-3000 mg·L^-1） was above 95.0%， and the degradation process of aniline showed first-order and zero-order kinetics. The growth process of Q6 conformed to the Haldane equation with a maximum specific growth rate μ_max of 0.130 h^-1， a half-satiation constant K_s of 190 mg·L^-1 and the inhibition constant K_i of 8497 mg·L^-1. The results show that strain Q6 has unique potential in the treating industrial wastewater containing high concentration of aniline.

Abstract:The wastewater generated in the production process of dinitrotoluene（DNT） is characterized by complex composition and difficult biodegradation. In this study， the idea of O₃/Fe（Ⅱ） oxidation enhanced by high gravity to degrade actual DNT wastewater was proposed. The effect of operating parameters on DNT wastewater removal was studied， and the catalytic mechanism of O₃/Fe（Ⅱ） oxidation degradation of DNT enhanced by high gravity was revealed. The intermediate products in DNT degradation process were analyzed， and the degradation pathway was speculated.The results showed that the increase of the high gravity factor facilitated the deep degradation of nitro compounds， and the pH of the system affected the direct and indirect oxidation reactions of ozone and the concentration of catalyst Fe（Ⅱ）. Under the conditions of high gravity factor （β）of 40， the Fe（Ⅱ） concentration of 0.8 mmol·L^-1 ， the O₃ concentration of 60 mg·L^-1 ， liquid flow（Q_L）of 80 L·h^-1 and pH of 1.1， 60% of nitro compounds were removed after the reaction for 60 min. Under similar operating conditions， the removal rate of nitro compounds was 18.30% higher than that of the bubbled reactor （BR） O₃/Fe（Ⅱ） system. The electron paramagnetic resonance spectrum showed the relative peak intensity of 1∶2∶2∶1， indicating the existence of hydroxyl radical （·OH） ， confirming that the degradation process followed the catalytic mechanism of ·OH. The intermediates of DNT degradation in rotating packed bed（RPB）O₃/Fe（Ⅱ） system mainly include dinitrobenzaldehyde， dinitrobenzoic acid， dinitrobenzene， resorcinol， malonic acid. The degradation pathway of Fe（Ⅱ）-catalyzed ozonation of dinitrotoluene was speculated.

Abstract:In order to treat the harmful acid wastewater from the refining process of 3-nitro-1，2，4-triazol-5-one （NTO）， the basic ion exchange resin was used to treat the wastewater and recover NTO. The resin with better adsorption effect was screened among four commercial resins（D301，D201，D311，IRA402）， and the effects of adsorption time and initial concentration on the adsorption of NTO by the resins were studied. In the dynamic adsorption experiment， the pH， initial concentration and flow rate of the simulated wastewater were screened to obtain the best adsorption conditions， and the desorption agent with better effect was screened. Five repeated experiments of adsorption and desorption were carried out under optimal conditions， and the desorption solution was acidified and extracted to recover NTO. The results show that D301 wet resin has good adsorption capacity for NTO， and the adsorption curve conforms to Langmuir equation. The theoretical saturated adsorption capacity can be inferred from the equation to be 232 mg·mL^-1. When the initial concentration of the simulated wastewater is 8 mg·mL^-1， the flow rate is 3 BV·h^-1， and the pH is 3， the adsorption effect of D301 is the best， and the saturated adsorption capacity is 205 mg·mL^-1. The resin is desorbed by 10% NaOH solution， and the best desorption rate can reach 98%. In repeated experiments， the recovery rate of NTO is 82%-88%， indicating that the resin has stable performance and can be recycled. In conclusion， the method of using basic ion exchange resin to adsorb NTO in wastewater is feasible and has practical application prospect.

Abstract:The special polycylic cage structure of the typical third-generation energy-containing material hexanitrohexaazoisowoodsane （CL-20） makes its production process accompanied by high concentration of organic solvents， which has large biological toxicity. In order to solve the serious pollution emission caused by CL-20 production. A combined internal electrolysis-alkaline hydrolysis-biodegradation process was proposed. Firstly， nitro compounds were reduced by zero-valent. Ethyl acetate and chloroform could be decomposed to small molecular organic acids by alkaline hydrolysis. Then， organic pollutants in wastewater were removed by anaerobic-aerobic biological combination process. The results indicated that CL-20 in the wastewater was thoroughly removed at the optimal reaction pH of 2. For alkaline hydrolysis process， the optimal pH value and treatment time was found to be 11.0 and 4 h， respectively. The removal efficiencies of ethyl acetate and chloroform reached （99.4±0.1）% and （95.4±0.9）%， respectively. Biodegradability could be improved by internal electrolysis-alkaline hydrolysis pretreatment. The chemical oxygen demand （COD） in effluent could be as low as 300 mg·L^-1 during the integrated biological process of upflow anaerobic sludge reactor （UASB） and biological aerated filter （BAF）. The combined internal electrolysis-alkaline hydrolysis-biodegradation process offers bright prospects for the treatment of wastewater from the manufacture of CL-20.

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