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1.
Reduction of NO
x
/SO2 by Wire-plate Type Pulsed Discharge Reactor with Pulsed Corona Radical Shower
Ke-Feng Shang Yan Wu Jie Li Guo-Feng Li Duan Li Ning-Hui Wang 《Plasma Chemistry and Plasma Processing》2006,26(5):443-454
Pulsed discharge deNO
x
/deSO2 process has been studied for over 20 years, but how to achieve higher removal rate at lower cost remains one of the crucial issues for realization of its industrial application. This paper presents a novel deNO
x
/deSO2 process that combines a wire-plate type pulsed discharge reactor and a corona radical shower. Our aim is to increase the deNO
x
/deSO2 rate of wire-plate type reactor by enhancing the generation of radicals with pulsed corona radical shower. Effect of a nozzle electrode on the production of OH radical was studied by emissive spectrum, and deNO
x
/deSO2 experiments using a wire-plate reactor with pulsed corona radical shower were conducted. The experimental results demonstrated that corona radical shower could enhance the production of radicals and the deNO
x
/SO2 performance of a wire-plate reactor. This study will play a positive role in the industrial application of wire-plate pulsed discharge deNO
x
/deSO2 reactor. 相似文献
2.
Ogata A. Yamanouchi K. Mizuno K. Kushiyama S. Yamamoto T. 《Plasma Chemistry and Plasma Processing》1999,19(3):383-394
The combination of plasma discharge and adsorption was examined for oxidation of dilute benzene in air in a plasma reactor packed with a mixture of BaTiO
3
pellets and porous Al
2
O
3
pellets (i.e., an alumina hybrid reactor). The oxidative decomposition of benzene was enhanced by the benzene concentrating on the Al
2
O
3
pellets. Furthermore, there was a higher selectivity to CO
2
in the products from the hybrid than from a plasma reactor packed with BaTiO
3
pellets alone. The presence of the Al
2
O
3
pellets suppressed the formation of N
2
O. 相似文献
3.
Lim JM Kim SW Hwang HJ Joo JH Kim HO Choi JW Yun JW 《Applied biochemistry and biotechnology》2004,119(2):159-170
Optimization of submerged culture conditions for the production of mycelial growth and exopolysaccharides (EPSs) by Collybia maculata was investigated. The optimum temperature and the initial pH for EPS production in a shake-flask culture of C. maculata were found to be 20°C and 5.5, respectively. Among the various medium’s constituents examined, glucose, Martone A-1, K2HPO4, and CaCl2 were the most suitable carbon, nitrogen, and mineral sources for EPS production, respectively. The optimum concentration
of the medium’s ingredients determined using the orthogonal matrix method was as follows: 30 g/L of glucose, 20 g/L of Martone
A-1, 1g/L of K2HPO4, and 1g/L of CaCl2. Under the optimized culture conditions, the maximum concentration of EPSs in a 5-L stirred-tank reactor was 2.4 g/L, which
was approximately five times higher than that in the basal medium. A comparative fermentation result showed that the EPS productivity
in an airlift reactor was higher than that in the stirred-tank reactor despite the lower mycelial growth rate. The specific
productivities and the yield coefficients in the airlift reactor were higher than those in the stirred-tank reactor even though
the volumetric productivities were higher in the stirred-tank reactor than in the airlift reactor. 相似文献
4.
Yu-Chuan Liang Can-Yong Jhu Sheng-Hung Wu Sun-Ju Shen Chi-Min Shu 《Journal of Thermal Analysis and Calorimetry》2011,106(1):173-177
Methyl ethyl ketone peroxide (MEKPO) is generally applied to manufacturing in the polymerization processes. Due to thermal
instability and high exothermic behaviors of MEKPO, if any operation is undertaken recklessly or some environmental effect
is produced suddenly during the processes, fires and explosions may inevitably occur. In this study, thermal analysis was
evaluated for MEKPO by differential scanning calorimetry (DSC) test. Vent sizing package 2 (VSP2) was used to analyze the
thermal hazard of MEKPO under various stirring rates in a batch reactor. Thermokinetic and safety parameters, including exothermic
onset temperature (T
0), maximum temperature (T
max), maximum pressure (P
max), self-heating rate (dT dt
−1), pressure rise rate (dP dt
−1), and so on, were discovered to identify the safe handling situation. The stirring rates of reactor were confirmed to affect
runaway and thermal hazard characteristics in the batch reactor. If the stirring rate was out of control, it could soon cause
a thermal hazard in the reactor. 相似文献
5.
Morteza Jafarikojour Morteza Sohrabi Sayed Javid Royaee 《Journal of Dispersion Science and Technology》2019,40(3):338-345
A new immobilized photocatalytic impinging jet stream reactor was designed, and the influences of the effective parameters like jet flow rate, TiO2 coating disc diameter, nozzle-to-disc distance, and initial concentration on phenol removal were investigated. The reactor was also used as a slurry reactor, and degradation efficiencies in both reactors were compared based on their catalyst loading. The results indicated that the slurry reactor has a higher degradation efficiency than the immobilized reactor at the same TiO2 loading and other operational conditions. The slurry reactor needs to separate and recover the TiO2 nanoparticles from the reaction medium which increases the overall process complexity and cost, while the immobilized reactor could be reused at least 4times without any significant decrease in removal efficiency. RTD result indicates that the tank in series model (N?=?5) could properly predict the reactors hydrodynamic behavior. 相似文献
6.
The conversion of a 1:1 CH
4
/CO
2
mixture to H
2
and CO was shown to occur at ambient temperature in a silent discharge reactor. Conversions of up to 50% were achieved with two reactors in series with a total residence time of 3 min at 13kV and 25 mA. 相似文献
7.
Jong-Hwa Moon Sun-Ha Kim Yong-Sam Chung Young-Jin Kim 《Journal of Radioanalytical and Nuclear Chemistry》2007,271(2):289-295
The k
0-standardization method (k
0-NAA) is known as one of the most remarkable progresses of the NAA with its many advantages. For the application of k
0-NAA method at the NAA #1 irradiation position where the neutrons are well thermalized in the HANARO research reactor, KAERI,
Korea, the determination of the reactor neutron spectrum parameters such as α and f have been carried out. The measured values of α and f using the “Cd-ratio” triple monitor method were 0.127±0.022 and 1010±70, respectively. To evaluate the applicability of k
0-NAA in our analytical system, the analysis of three kinds of SRMs was executed. The analytical results showed that the relative
error of most of the elements was less than 10% and the U-scores were within 2. It is turned out that the procedure of the k
0-NAA in the HANARO research reactor is available for a practical application in the environmental fields. 相似文献
8.
Keiichiro Yoshida Toshiaki Yamamoto Tomoyuki Kuroki Masaaki Okubo 《Plasma Chemistry and Plasma Processing》2009,29(5):373-386
A pilot-scale pulse corona induced plasma chemical process (PPCP) reactor for controlling gas-phase dioxins and NO
x
simultaneously is installed in a garbage incineration plant. The flow rate of the sampled flue gas is 5,000 Nm3/h (N: standard state) in maximum at the PPCP reactor, which consists of 22 wire-cylinder electrodes and is energized by a
50 kW nanosecond pulse high voltage generator. With an applied plasma energy density of 2.9–6.1 Wh/Nm3, the decomposition efficiency for dioxins is 75–84% based on TEQ (toxic equivalents); the conversion efficiency of NO to
NO2 is ~93% at maximum. The flue gas treated by the PPCP reactor is introduced at a rate of 50 Nm3/h to a wet-type chemical reactor, which uses an aqueous solution of sodium sulfite (Na2SO3). More than 90% of NO
x
is reduced to nitrogen, with negligible byproducts such as NO2
− or NO3
− ions left in the solution. 相似文献
9.
Nataša D. Pejić Slavica M. Blagojević Nataša B. Sarap Jelena P. Maksimović Slobodan R. Anić Željko D. Čupić Ljiljana Z. Kolar‐Anić 《Helvetica chimica acta》2014,97(1):47-55
Perturbation of the Bray? Liebhafsky non‐oscillating subsystem (mixture of KIO3 and H2SO4), i.e., Dushman reaction (DR), by piroxicam (PX), was observed in an open reactor, i.e., in the continuously fed well‐stirred tank reactor (CSTR). Monitoring the response of DR to perturbations by different concentrations of PX allows developing a simple procedure for quantitative determination of this analyte in both bulk drug and pharmaceutical preparation (injection). A tentative perturbation mechanism of PX action on the DR matrix, based on a kinetic scheme that was suggested by Agreda et al., is proposed. The PX reactivity in DR has been generally related to the reaction of PX with hypoiodous acid (HIO) present in the matrix. 相似文献
10.
This work reports on the removal of organic matter and nitrogen in a radial-flow aerobic-anoxic immobilized biomass (RAIB)
reactor fed with domestic sewage pretreated in a horizontal-flow anaerobic immobilized biomass (HAIB) reactor. Polyurethane
foam was used as support material for biomass attachment in both reactors. In batch experiments, a first-order kinetic model
with residual concentration represented the organic matter removal rate, whereas nitrogen conversion followed a pseudo-first-order
reaction in series model, with kinetic constants k
1 (ammonium to nitrite) and k
2 (nitrite to nitrate) of 0.25 and 6.62 h−1, respectively. The RAIB reactor was operated in continuous-flow mode and changes in the airflow rate and hydraulic retention
time were found to interfere in the apparent kinetic constants to the nitritation (k
1) and nitratation (k
2). Nitrification and denitrification were achieved in the partially aerated RAIB reactor operating with hydraulic retention
times of 3.3 h and 2.7 h in the aerobic and anoxic zones, respectively. Ethanol was added in the anoxic zone of the reactor
to promote denitrification. The effluent flow of the RAIB reactor presented a COD of 52 mg l−1, and concentrations of 2 mg , 1.24 mg and 3.46 mg . 相似文献
11.
In recent years the k
0-NAA method has been applied and developed at the 500 kW Dalat research reactor, which includes (1) the establishment of a PC database of k
0-NAA-related nuclear parameters, e.g., radionuclide produced, half-lives, k
0-factors, Q
0, r, E
g, etc; the access to the database is able by a k
0-NAA software or by manual; (2) the detection efficiency calibration of gamma spectrometers used in k
0-NAA, (3) the determination of reactor neutron spectrum parameters such as a and f factors and neutron fluxes in the irradiation channels, and (4) the validation of the developed k
0-NAA procedure by analysing some SRMs, namely Coal Fly Ash (NIST-1633b), Bovine Liver (NIST-1577b) and IAEA-Soil7. The analytical results showed the deviations between experimental and certified values were mostly less than 15% with most Z-scores lower than 2. The k
0-NAA procedure established at the Dalat research reactor has been regarded as a reliable standardization method of NAA and as available for practical applications, in particularly for airborne particulate and crude oil samples. 相似文献
12.
The kinetics of ethylene oxidation by PdCl2 and CrO3 complexes supported on silica gel (300 K, closed batch reactor) and the adsorption of C2H4 by silica gel and metal complex reaction centers (M
n
) were studied. A new version of the kinetic distribution method was applied to determine the rate constants of ethylene reactions with metal complexes with consideration for the equilibrium distribution of C2H4 among the reactor gas phase, silica gel, and M
n
. The rate constant of a first-order reaction with respect to Cr(VI) (k
e) remained constant as [M
n
] was increased up to 0.15 mol % with the absence of detectable ethylene adsorption by chromium(VI). In the case of Pd(II)/SiO2, strong ethylene adsorption by palladium(II) was found, and k
e was an exponential function of [M
n
]. This exponential function is indicative of an increase in the specific activity of Pd(II) with palladium concentration on SiO2. Taking into account the adsorption of ethylene (physisorption on SiO2 and chemisorption on Pd(II)), we found an analogy between the kinetic behaviors of Pd(II) in reactions with ethylene on silica gel and with ethylene and other hydrocarbons in solutions. 相似文献
13.
Hassouni K. Leroy O. Farhat S. Gicquel A. 《Plasma Chemistry and Plasma Processing》1998,18(3):325-362
One-dimensional transport models of moderate-pressure H
2
and H
2
/CH
4
plasmas obtained in a diamond deposition microwave reactor are presented. These models describe the plasma as a thermochemically nonequilibrium flow with three different energy modes. The solution of the one-dimensional plasma transport equations enabled the estimation of plasma species concentrations and temperatures on the axis of the reactor. As far as pure H
2
plasmas are concerned, results showed that the model predictions of gas and vibration temperatures are in good agreement with experimental measurements. The model also yields a relatively good qualitative prediction of the variations of H-atom mole fraction with the power density absorbed by the plasma. The results obtained for H
2
/CH
4
discharges showed that the model prediction on the variations of H-atom mole fraction with methane percentage in the discharge is in good qualitative agreement with experimental results. They also showed that methane is rapidly converted to acetylene before reaching the discharge zone. The concentrations of neutral hydrocarbon species in the reactor are mainly governed by thermal chemistry. The addition of methane strongly affects the ionization kinetics of the plasma. Three major ions are generally obtained in H
2
/CH
4
plasmas: C
2
H
2
+
, C
2
H
3
+
, and C
2
H
5
+
. The relative predominance of these ions depends on the considered plasma region and on the discharge conditions. The ionic species concentrations are also mainly governed by chemistry, except very near the substrate surface. Finally the use of this transport model along with the surface chemistry model of Goodwin
(1)
enabled us to estimate the diamond growth rate for several discharge conditions. 相似文献
14.
Heidi Van Parys Els Tourw Tom Breugelmans Marnix Depauw Johan Deconinck Annick Hubin 《Journal of Electroanalytical Chemistry》2008,622(1):44-50
In this work, the validation of a newly constructed inverted rotating disk electrode (IRDE) reactor is reported. Compared to the rotating disk electrode (RDE) reactor, the working electrode is changed in position from the top to the bottom of the electrochemical cell. The IRDE reactor is designed to facilitate the actual study of gas evolution reactions. It is studied whether the first-order analytical expression for the velocity field in an RDE reactor is also acceptable for an IRDE configuration. To that purpose, the kinetic parameters of the well-known ferri/ferro cyanide redox system are determined in both configurations and compared. This is done qualitatively by comparing the polarization curves obtained in the inverted and the conventional RDE configuration. Additionally, a statistically founded fitting algorithm is used to quantitatively determine the model parameters of the oxidation and reduction reaction. Not only the diffusion coefficients of Fe2+ and Fe3+ are calculated, but also the rate constants (kox and kred) and the transfer coefficients (αox and αred) are quantified and compared together with their respective standard deviation. It is found that the parameters of mass and charge transfer in both configurations agree well. So it is concluded that the same analytical equations of mass and charge transfer can be used in both the RDE and the IRDE reactor. 相似文献
15.
The kinetics of the reaction of methanol with hydrogen sulfide in the presence of an IKT-31 catalyst was experimentally studied. The experiments were performed in a fixed-bed flow reactor under the following conditions: T = 598-653 K, P = 0.1-1.0 MPa, and P0
H
2
S/P0
Me =0.4-15.0. Rate equations were derived which describe the rates of formation of methanethiol as the main product and dimethyl sulfide and dimethyl ether as by-products. The rate constants and activation energies were found by the mathematical treatment of experimental data. The model proposed can be used for reactor design. 相似文献
16.
Ying-Jun Wang Xin-ping Wang Song-Hai Chai Tian-Xi Cai 《Reaction Kinetics and Catalysis Letters》2002,77(1):125-132
The dynamics of n-heptane isomerization on the reduced MoO3 catalyst have been studied in a fixed bed flow reactor. In the reaction temperature ranging from 523 to 673 K, the apparent energy for n-heptane isomerization obtained from the Arrhenius plot was 49.3 kJ/mol. At 573 K, the reaction orders of 0.33 in n-heptane and 0.35 in H2 have been obtained. 相似文献
17.
This study was undertaken to identify factors exerting the strongest influence on the adsorption of dye. The maximum adsorption
capacity (at the adopted operating conditions) was the main parameter used to evaluate the process. In addition, the feasible
adsorption capacity of chitosan was evaluated. Breakthrough experiments were carried out in a circulating air-lift reactor
at a constant concentration of reactive dye Black 8 (100 mg/dm3). The tests studied different chitosan concentrations in the reactor and a range of flow intensities. The results of the
breakthrough tests were compared by means of apparent mass transfer coefficients, determined by slopes at C/C
0=1/2. The adsorption capacity of chitosan was affected to the greatest extent by the flow rate of the medium to the reactor.
In turn, the utilization of the maximum adsorption capacity of chitosan, at the assumed efficiency of dye removal, was determined
by chitosan concentration in the reactor. 相似文献
18.
The rate coefficient for the reaction of the peroxypropionyl radical (C2H5C(O)O2) with NO was measured with a laminar flow reactor over the temperature range 226–406 K. The C2H5C(O)O2 reactant was monitored with chemical ionization mass spectrometry. The measured rate coefficients are k(T) = (6.7 ± 1.7) × 10−12 exp{(340 ± 80)/T} cm3 molecule−1 s−1 and k(298 K) = (2.1 ± 0.2) × 10−11 cm3 molecule−1 s−1. Our results are comparable to recommended rate coefficients for the analogous CH3C(O)O2 + NO reaction. Heterogeneous effects, pressure dependence, and concentration gradients inside the flow reactor are examined. © 1999 John Wiley & Sons, Inc. Int J Chem Kinet: 31: 221–228, 1999 相似文献
19.
Sherly K. Bhaskaran Thrivikrama T. Venugopal 《Reaction Kinetics and Catalysis Letters》2001,74(1):99-102
The liquid phase benzoylation of o-xylene with benzoyl chloride over rare earth oxide catalysts like CeO2 and Pr2O3 is studied in a batch reactor at atmospheric pressure and 411 K. Surface area, pore volume, acid strength distribution on
the catalyst surface and optimum temperature of the catalyst are reported.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
20.
The liquid phase benzylation of o-xylene with benzyl chloride over rare earth oxide catalysts like CeO2 and Pr2O3 was studied in a batch reactor at atmospheric pressure and 363 K. Surface area, pore volume, DTA, acid strength distribution on the catalyst surface and optimum temperature of the catalyst are reported. 相似文献