Kinetic Research of Boron Oxide Reducing Reaction at Low Temperature

2012 ◽  
Vol 512-515 ◽  
pp. 2372-2375 ◽  
Author(s):  
Ding Guo Zhao ◽  
Shu Huan Wang ◽  
Xiao Jie Cui ◽  
Jian Long Guo

The reducing process of boron-containing slag at low temperature is an important stage of the direct alloying for smelting boron steel. At low temperature boron slag generates mainly solid - solid reaction in the sintering period. The experiments were done on the carbon tube furnace in laboratory, and the effect of slag reaction in different times at 1200°C was researched. The samples were analyzed by XRD after the reaction. The experimental results shown that the reduction rate increased by increasing reducing time. The chemical reducing reaction of boron oxide by ferrosilicon is second-order reaction at solid state.

2012 ◽  
Vol 236-237 ◽  
pp. 751-754
Author(s):  
Ding Guo Zhao ◽  
Shu Huan Wang ◽  
Xiao Jie Cui ◽  
He Jun Zhang

In the paper, the reaction of solid-solid model was researched and we confirmed the reaction equation. The experiments in the lab shown that the t1/2 is 11.8min in the ferrosilicon reduction boron anhydride reaction at low temperature. The yield of boron is higher by direct reduction method smelting. In the boron oxide reducing experiment, the yield minimum is 76%, the maximum is 82%, and the average value is about 79%, which provides favorable foundation conditions for smelting amorphous mother alloy.


2019 ◽  
Vol 38 (2019) ◽  
pp. 905-915
Author(s):  
Yuekai Xue ◽  
Chenxiao Li ◽  
Chaogang Zhou ◽  
Dingguo Zhao ◽  
Shuhuan Wang

AbstractThe high-P content in steel slag limits its utilization in the next heats of steelmaking. In this work, P2O5-containing slag was reduced by carbon at high temperatures with flowing N2. The P-containing substances in the off-gas were collected after water cooling. Both XRD analysis and thermodynamic calculations indicate that the gas produced by P2O5 reduction is mainly composed of P2. The actual reduction Gibbs free energy of P2O5 is less than that of FeO; while the reduction rate of FeO is higher than that of P2O5 due to the good kinetic conditions and the low activation energy. The reduction of P2O5 agrees well with the second-order reaction, whose reduction rate is controlled by the mass transfer in the slag. The reduction of FeO agrees well with the first-order reaction, whose reduction rate is mainly controlled by the interface chemical reaction.


1971 ◽  
Vol 6 (1) ◽  
pp. 249-272
Author(s):  
P.B. Melynk ◽  
J.D. Norman ◽  
A.W. Wilson

Abstract It is postulated that the mixing conditions in a flow-through reactor can be characterized as having either completely mixed, completely plug flow, or some network of completely mixed and plug flow component vessels. A frequency-response technique is used to obtain an experimental Bodé plot for arbitrarily mixed vessels. The interpretation of the Bodé plot is discussed, and , in light of this interpretation, a network of plug flow and completely mixed components is specified as a flow model. A Rosenbrock search routine is used to improve the parameter estimates of the model. To verify the model, a second order reaction was run through the vessel and the experimentally measured conversion was compared to that predicted by the model. It is shown that the modeling technique, in addition to describing the mixing in the system, will indicate inactive volume, as well as measure the extent of any channeling or short circuiting in the reactor.


1985 ◽  
Vol 50 (7) ◽  
pp. 1594-1601 ◽  
Author(s):  
Jiří Klíma ◽  
Larisa Baumane ◽  
Janis Stradinš ◽  
Jiří Volke ◽  
Romualds Gavars

It has been found that the decay in dimethylformamide and dimethylformamide-water mixtures of radical anions in five of the investigated 5-nitrofurans is governed by a second-order reaction. Only the decay of the radical anion generated from 5-nitro-2-furfural III may be described by an equation including parallel first- and second-order reactions; this behaviour is evidently caused by the relatively high stability of the corresponding dianion, this being an intermediate in the reaction path. The presence of a larger conjugated system in the substituent in position 2 results in a decrease of the unpaired electron density in the nitro group and, consequently, an increase in the stability of the corresponding radical anions.


1983 ◽  
Vol 48 (11) ◽  
pp. 3279-3286
Author(s):  
Slavko Hudeček ◽  
Miloslav Bohdanecký ◽  
Ivana Hudečková ◽  
Pavel Špaček ◽  
Pavel Čefelín

The reaction between hexamethylenediisocyanate and 1-pentanol in toluene was studied by means of reversed-phase liquid chromatography. By employing this method, it was possible to determine all components of the reaction mixture including both products, i.e. N-(6-isocyanate hexyl)pentylcarbamate and N,N'-bis(pentyloxycarbonyl)hexamethylenediamine. Relations for the calculation of kinetic constants were derived assuming a competitive consecutive second-order reaction. It was demonstrated that the reaction involved in this case is indeed a second-order reaction, and the rate constants of the first and second consecutive reactions were determined.


1992 ◽  
Vol 57 (6) ◽  
pp. 1326-1334 ◽  
Author(s):  
Jaroslav Vojtěchovský ◽  
Jindřich Hašek ◽  
Stanislav Nešpůrek ◽  
Mojmír Adamec

2,4,4,6-Tetraphenyl-4H-thiopyran, C29H22S, orthorhombic, Pna21, a = 17.980(4), b = 6.956(2), c = 34.562(11) Å, V = 4323(2) Å3, Z = 8, Dx = 1.237 g cm-3, F(000) = 1696, λ(CuKα) = 1.54184 A, μ = 1.372 mm-2, T = 294 K. The final R was 0.050 for the unique set of 3103 observed reflections. The central 4H-thiopyran ring forms a boat conformation for both symmetrically independent molecules with average boat angles 4.4(3) and 6.8(3)° at S and C(sp3), respectively. The mean planes of phenyls at the position 2 and 6 are turned from the double plane of 4H-thiopyran by 42.5(5) and 35.8(3)°, respectively. The investigated material undergoes a photochromic change in the solid state after irradiation with UV light or X-rays. The maximum of the new absorption band is situated at 564 nm. The non-exponential time dependence of photochromic bleaching is analysed in terms of a dispersive first-order reaction.


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