Iron-based amorphous electrode material for wastewater treatment and use thereof

Abstract

An iron-based amorphous electrode material for industrial wastewater treatment, wherein the material is amorphous alloy used as an electrode for electrochemical degradation of industrial wastewater, and the atom percentage of iron element in the alloy being 40-84%, wherein a method for treating dye wastewater by using the iron-based amorphous electrode material and a use of the iron-based amorphous electrode material in the electrochemical degradation of industrial wastewater are also disclosed.

Claims

1. An iron-based amorphous electrode for industrial wastewater treatment, wherein the iron-based amorphous electrode is made of an iron-based amorphous alloy, wherein the iron-based amorphous electrode defines a ribbon, wherein the atomic percentage of iron element in the iron-based amorphous alloy is 65% to 84%, and the remaining alloying element is one or more elements selected from the group consisting of P, C, Mo, Ni and Co.

2. An iron-based amorphous electrode for industrial wastewater treatment, wherein the iron-based amorphous electrode is made of an iron-based amorphous alloy, wherein the atomic percentage of iron element in the iron-based amorphous alloy is 40% to 84%, wherein the iron-based amorphous electrode defines a ribbon, and the remaining alloying element is one or more elements selected from the group consisting of P, C, Mo, Ni and Co.

3. An iron-based amorphous electrode for industrial wastewater treatment, wherein the iron-based amorphous electrode is made of an iron-based amorphous alloy, wherein the atomic percentage of iron element in the iron-based amorphous alloy is 40% to 84%, wherein the iron-based amorphous electrode defines a ribbon, wherein the iron-based amorphous electrode is made of one or more iron-based amorphous alloys selected from the group consisting of Fe.sub.83Si.sub.4B.sub.10P.sub.2Cu.sub.1 (at. %), Fe.sub.65Co.sub.13Si.sub.8B.sub.14 (at. %), Fe.sub.40Co.sub.38Si.sub.8B.sub.14 (at. %), Fe.sub.68Ni.sub.10Si.sub.8B.sub.14 (at. %) and Fe.sub.50Ni.sub.28Si.sub.8B.sub.14 (at. %).

4. A method for treating industrial wastewater, comprising the following steps: putting an iron-based amorphous electrode into the industrial wastewater, wherein the iron-based amorphous electrode is made of an iron-based amorphous alloy, wherein the atomic percentage of iron element in the iron-based amorphous alloy is 40% to 84%; applying a potential to the iron-based amorphous electrode, wherein the potential is 0 to 5V and controlling the current flowing through the iron-based amorphous electrode to be 0.005A to 1A; and maintaining the temperature of the industrial wastewater at ambient temperature to 100° C.

5. The method for treating industrial wastewater, as recited in claim 4, further comprising the following step: adjusting the pH of the industrial wastewater at 1˜12.

6. The method for treating industrial wastewater, as recited in claim 4, further comprising the following step: stirring the industrial wastewater by a stirrer at a speed of 100 rpm˜800 rpm.

7. The method for treating industrial wastewater, as recited in claim 5, further comprising the following step: stirring the industrial wastewater by a stirrer at a speed of 100 rpm˜800 rpm.

8. The method for treating industrial wastewater, as recited in claim 4, wherein the iron-based amorphous electrode defines a ribbon.

9. The method for treating industrial wastewater, as recited in claim 8, wherein the ribbon has a thickness of 15 μm−100 μm.

10. The method for treating industrial wastewater, as recited in claim 4, wherein the atomic percentage of iron element in the iron-based amorphous alloy is 70% to 84%, and the remaining alloying element is one or more elements selected from the group consisting of P, C, Mo, Ni and Co.

11. The method for treating industrial wastewater, as recited in claim 4, wherein the iron-based amorphous electrode is made of one or more iron-based amorphous alloys selected from the group consisting of Fe.sub.83Si.sub.4B.sub.10P.sub.2Cu.sub.1 (at. %), Fe.sub.65Co.sub.13Si.sub.8B.sub.14 (at. %), Fe.sub.40Co.sub.38Si.sub.8B.sub.14 (at. %), Fe.sub.68Ni.sub.10Si.sub.8B.sub.14 (at. %) and Fe.sub.50Ni.sub.28Si.sub.8B.sub.14 (at. %).

12. The method for treating industrial wastewater, as recited in claim 5, wherein the iron-based amorphous electrode is made of one or more iron-based amorphous alloys selected from the group consisting of Fe.sub.83Si.sub.4B.sub.10P.sub.2Cu.sub.1 (at. %), Fe.sub.65Co.sub.13Si.sub.8B.sub.14 (at. %), Fe.sub.40Co.sub.38Si.sub.8B.sub.14 (at. %), Fe.sub.68Ni.sub.10Si.sub.8B.sub.14 (at. %) and Fe.sub.50Ni.sub.28Si.sub.8B.sub.14 (at. %).

13. The method for treating industrial wastewater, as recited in claim 6, wherein the iron-based amorphous electrode is made of one or more iron-based amorphous alloys selected from the group consisting of Fe.sub.83Si.sub.4B.sub.10P.sub.2Cu.sub.1 (at. %), Fe.sub.65Co.sub.13Si.sub.8B.sub.14 (at. %), Fe.sub.40Co.sub.38Si.sub.8B.sub.14 (at. %), Fe.sub.68Ni.sub.10Si.sub.8B.sub.14 (at. %) and Fe.sub.50Ni.sub.28Si.sub.8B.sub.14 (at. %).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows the XRD patterns of an iron-based amorphous alloy Fe.sub.73.5Nb.sub.3Cu.sub.1Si.sub.13.5B.sub.9 (at. %) ribbon, before and after reaction of degrading an acidic orange II solution.

(2) FIG. 2 is a graph showing the time variation of the UV-visible absorption spectrum of an acidic orange II solution, and the time variation of C.sub.t/C.sub.0 of the acidic orange II solution, under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.73.5Nb.sub.3Cu.sub.1Si.sub.13.5B.sub.9 (at. %) ribbon, wherein the electrode voltage is 0.5V and the solution temperature is 60° C.

(3) FIG. 3 is a graph showing the time variation of the UV-visible absorption spectrum of the acidic orange II solution, and the time variation of C.sub.t/C.sub.0 of the acidic orange II solution, under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.73.5Nb.sub.3Cu.sub.1Si.sub.13.5B.sub.9 (at. %) ribbon, wherein the electrode voltage is 1V and the solution temperature is 60° C.

(4) FIG. 4 is a graph showing the time variation of the UV-visible absorption spectrum of the acidic orange II solution and the time variation of C.sub.t/C.sub.0 of the acidic orange II solution, under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.73.5Nb.sub.3Cu.sub.1Si.sub.13.5B.sub.9 (at. %) ribbon, wherein the electrode voltage is 0V and the solution temperature is 60° C.

(5) FIG. 5 is a graph showing the time variation of the UV-visible absorption spectrum of the acidic orange II solution and the time variation of C.sub.t/C.sub.0 of the acidic orange II solution, under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.78Si.sub.8B.sub.14 (at. %) ribbon, wherein the electrode voltage is 1V and the solution temperature is 60° C.

(6) FIG. 6 is a graph showing the time variation of the UV-visible absorption spectrum of the acidic orange II solution and the time variation of C.sub.t/C.sub.0 of the acidic orange II solution, under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.83Si.sub.4B.sub.10P.sub.2Cu.sub.1 (at. %) ribbon, wherein the electrode voltage is 1V and the solution temperature is 60° C.

(7) FIG. 7 is a graph showing the time variation of C.sub.t/C.sub.0 of the acidic orange II solution, under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.65Co.sub.13Si.sub.8B.sub.14 (at. %) ribbon, wherein the electrode voltage is 1V and the solution temperature is 60° C.

(8) FIG. 8 is a graph showing the time variation of C.sub.t/C.sub.0 of the acidic orange II solution, under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.40Co.sub.38Si.sub.8B.sub.14 (at. %) ribbon, wherein the electrode voltage is 1V and the solution temperature is 60° C.

(9) FIG. 9 is a graph showing the time variation of C.sub.t/C.sub.0 of the acidic orange II solution, under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.68Ni.sub.10Si.sub.8B.sub.14 (at. %) ribbon, wherein the electrode voltage is 1V and the solution temperature is 60° C.

(10) FIG. 10 is a graph showing the time variation of C.sub.t/C.sub.0 of the acidic orange II solution, under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.50Ni.sub.28Si.sub.8B.sub.14 (at. %) ribbon, wherein the electrode voltage is 1V and the solution temperature is 60° C.

(11) FIG. 11 is two photographs showing respectively the acid orange II solution samples before and after reaction, under the degradation of Fe.sub.73.5Nb.sub.3Cu.sub.1Si.sub.13.5B.sub.9 ribbon, wherein the electrode voltages is respectively 1V and 0V.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(12) The present invention prepares an iron-based amorphous alloy ribbon by utilizing a ribbon-casting method, which is mainly concentrated in an alloy system of Fe—B, Fe—Si—B, Fe—Co—Si—B, Fe—Ni—Si—B, Fe—Si—B—P, Fe—Si—B—Mo, Fe—Si—B—Nb, Fe—Si—B—P—Cu, Fe—Si—B—Nb—Cu, Fe—B—C, Fe—B—C—Nb, Fe—B—C—Cu, Fe—P—C, Fe—P—C—Cu and so on, and its typical nominal composition (atomic %), such as: Fe.sub.83B.sub.17, Fe.sub.78Si.sub.8B.sub.14, Fe.sub.65Co.sub.13Si.sub.8B.sub.14, Fe.sub.40Co.sub.38Si.sub.8B.sub.14, Fe.sub.68Ni.sub.10Si.sub.8B.sub.14, Fe.sub.50Ni.sub.28Si.sub.8B.sub.14, Fe.sub.83B.sub.10Si.sub.4P.sub.3, Fe.sub.77Si.sub.8B.sub.14Mo.sub.1, Fe.sub.74.5Nb.sub.3Si.sub.13.5B.sub.9, Fe.sub.83Si.sub.4B.sub.10P.sub.2Cu.sub.1, Fe.sub.73.5Nb.sub.3Cu.sub.1Si.sub.13.5B.sub.9, Fe.sub.84B.sub.10C.sub.6, Fe.sub.83Nb.sub.1B.sub.10C.sub.6, Fe.sub.83.5Cu.sub.0.5B.sub.10C.sub.6, Fe.sub.84P.sub.10C.sub.6, Fe.sub.83.25P.sub.10C.sub.6Cu.sub.0.75, etc., and they are applied to the electrochemical degradation test of dye wastewater, and the test results show that an electrode of the iron-based amorphous alloy ribbon has a good stability, a high degradation efficiency and greatly reduces electricity consumption, during the electrochemical degradation of the dye wastewater.

(13) FIG. 1 shows the XRD patterns of the iron-based amorphous alloy Fe.sub.73.5Nb.sub.3Cu.sub.1Si.sub.13.5B.sub.9 (at. %) ribbon, before and after reaction, and there is no distinctive difference between the XRD patterns of the ribbon before and after reaction, wherein the dispersion peaks illustrate the amorphous structures of the samples.

(14) The iron-based amorphous alloy ribbon is applied for electrochemically degrading the acidic orange II solution, by utilizing it as an electrode, wherein the surface area of the electrode participating in the reaction is 50 cm.sup.2, the concentration of the acidic orange II solution is 0.2 g/L, and the volume of the acidic orange II solution is 300 mL. Placing the beaker containing the acidic orange II solution in an electromagnetic stirring system, and then stirring the dye solution at a speed of 200 rpm, wherein the temperature is controlled at 60° C. The test is performed by selecting electrode voltages of 0.5V and 1V, respectively. After the start of the reaction, about 3 mL solution is taken at intervals to detect ultraviolet-visible absorption spectroscopy thereof. According to the spectroscopy knowledge, the maximum absorption peak of the acidic orange II solution is 484 nm, which represents its azo structure (—N=N—). The corresponding absorbance is proportional to the solubility of the solution, so the change of the solution solubility of the acidic orange II solution can be obtained by the change of the absorbance of the solution solubility of the acidic orange II solution at the maximum absorption peak. The comparison test is carried out when the electrode is under an open state thereof. In addition, when the electrode voltage is 0.5V, a high-purity iron foil is selected as the electrode for perform the comparison test.

(15) FIG. 2 is a graph showing the time variation of the UV-visible absorption spectrum of the acidic orange II solution, under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.73.5Nb.sub.3Cu.sub.1Si.sub.13.5B.sub.9 (at. %) ribbon. As shown in FIG. 2a, the electrode voltage is 0.5V. As the reaction time increases, the absorbance of the acidic orange II solution, at 484 nm, gradually decreases, which means that the azo bond (—N=N—) is continuously broken and the acid orange II is continuously degraded. FIG. 2a shows the kinetic curve of degradation of the acid orange II. After nonlinear fitting, it is found that the degradation process satisfies the pseudo first-order reaction:

(16) C.sub.t/C.sub.0=(I−C.sub.ult/C.sub.0) exp(−kt)+C.sub.ult/C.sub.0, wherein C.sub.t represents the solution concentration at time t, and Co represents the solution concentration at the initial time, C.sub.ult represents the final residual solution concentration, t represents the reaction time, t represents the reaction time, k represents the reaction rate constant, and the degradation efficiency η=I−C.sub.ult/C.sub.0.

(17) When the electrode voltage is 0.5V and the reaction time is 240 min, the degradation efficiency of the acidic orange II solution can reach 90.42%, and the rate constant obtained by fitting is 0.014 min.sup.−1. The calculated electrical energy consumption is 40.76 J, the electrical energy consumption per unit of degradation efficiency is 0.45 J/%, and the mass loss of the electrode is 16 mg. As a comparison, a high-purity iron foil is used as the electrode, and when the other experimental conditions are the same and the reaction time is 120 min, the degradation efficiency of the acidic orange II solution can reach 98.06%, the energy consumption is 91.65 J, and the electrical energy consumption per unit of degradation efficiency is 0.94 J/%, the mass loss of the electrode is 60 mg. In the experiment, the high-purity iron foil and the iron-based amorphous alloy ribbon have the same surface area, and the thickness of the iron foil (100 μm) is three times that of the iron-based amorphous alloy ribbon (30 μm), and the iron-based amorphous alloy contains a large amount of non-metallic elements. Therefore, the iron content per unit surface area of the iron-based amorphous alloy ribbon is much less than that of the high-purity iron foil. However, when the iron-based amorphous alloy ribbon is used as the electrode, the degradation efficiency of the acidic orange II can also be more than 90%. So to speak, the iron content per unit of the iron-based amorphous alloy ribbon as the electrode is more effective in degrading the acid orange II solution than that of the high-purity iron foil. Moreover, when the high-purity iron foil is used as the electrode, the energy consumption and mass loss of the electrode far exceeds that of the iron-based amorphous alloy ribbon as the electrode. Thus it can be seen that the iron-based amorphous alloy ribbon is used as the electrode for electrochemically degrading the acidic orange II solution, it has the advantages of high degradation efficiency, less electrode loss, long electrode life and low energy consumption, with respect to the high-purity iron foil.

(18) FIG. 3 shows the degradation process of the acidic orange II solution, when the electrode voltage is increased to 1V, under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.73.5Nb.sub.3Cu.sub.1Si.sub.13.5B.sub.9 (at. %) ribbon, wherein when the reaction time is 30 min, the degradation efficiency can reach 92.67%, and when the reaction time is 60 min, the degradation efficiency can reach 96.60%. Thus it can be seen that a certain increase of the electrode voltage is helpful to the degradation of the acidic orange II solution.

(19) FIG. 4 shows the degradation of the acidic orange II solution, when the electrode of the iron-based amorphous alloy Fe.sub.73.5Nb.sub.3Cu.sub.1Si.sub.13.5B.sub.9 (at. %) ribbon is under an open state. It can be seen that the acid orange II is slowly degraded in the absence of electrochemical action. When the reaction time is 30 min, the degradation efficiency is only 25.34%, and the reaction rate constant is 0.006 min.sup.−1. It can be seen that the reaction rate and degradation efficiency of the iron-based amorphous alloy ribbon is far greater than that without electricity, under electrochemical action, when it is used for degrading the acidic orange II solution.

(20) FIG. 5 shows the degradation process of the acidic orange II solution, when the electrode voltage is increased to 1V, under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.78Si.sub.8B.sub.14 (at. %) ribbon, wherein when the reaction time is 10 min, the degradation efficiency can reach 95.47%, and when the reaction time is 20 min, the degradation efficiency can reach 98.46%. Thus it can be seen that the degradation rate of acid orange II is accelerated, with the increase of Fe content in the iron-based amorphous alloy.

(21) In the following examples, the surface area of the electrode participating in the reaction is 5 cm.sup.2, the volume of the acidic orange II solution is 300 mL, and other conditions are unchanged.

(22) FIG. 6 shows the degradation process of the acidic orange II solution under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.83Si.sub.4B.sub.10P.sub.2Cu.sub.1 (at. %) ribbon, wherein when the reaction time is 18 min, the degradation efficiency can reach 97.32%, and the reaction rate constant is 0.295 min.sup.−1. FIG. 7 shows the degradation process of the acidic orange II solution under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.65Co.sub.13Si.sub.8B.sub.14 (at. %) ribbon, wherein when the reaction time is 20 min, the degradation efficiency can reach 96.19%, and the reaction rate constant is 0.225 min.sup.−1. FIG. 8 shows the degradation process of the acidic orange II solution under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.40Co.sub.38Si.sub.8B.sub.14 (at. %) ribbon, wherein when the reaction time is 14 min, the degradation efficiency can reach 97.94%, and the reaction rate constant is 0.435 min.sup.−1. It can be seen that the small addition of Co in the Fe-based amorphous alloy does not significantly affect the degradation effect, while the increase of the content of Co accelerates the rate of electrochemical degradation of the iron-based amorphous alloy ribbon.

(23) Similar to the Co element, the addition of a small amount of Ni in the Fe-based amorphous alloy has no significant effect on the degradation, and as the content of Ni increases, the rate of electrochemical degradation of the acidic orange II solution by the iron-based amorphous alloy ribbon accelerates, as shown in FIG. 9 and FIG. 10. FIG. 9 shows the degradation of the acidic orange II solution under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.68Ni.sub.10Si.sub.8B.sub.14 (at. %) ribbon, wherein when the reaction time is 20 min, the degradation efficiency can reach 96.19%, and the reaction rate constant is 0.217 min.sup.−1. FIG. 10 shows the degradation of the acidic orange II solution under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.50Ni.sub.28Si.sub.8B.sub.14 (at. %) ribbon, wherein when the reaction time is 20 min, the degradation efficiency can reach 95.67%, and the reaction rate constant is 0.327 min.sup.−1.

(24) FIG. 11 provides two sample photographs of the acid orange II solution before and after reaction, under the electrochemical degradation of the iron-based amorphous alloy Fe.sub.73.5Nb.sub.3Cu.sub.1Si.sub.13.5B.sub.9 ribbon, when the electrode voltages are 1V and 0V, respectively. It can be seen that when the acid orange II solution is under the action of electrochemistry and the reaction time is 60 min, the acid orange II solution is changed from the initial orange-red color to a colorless, and when the reaction is performed for 300 min without the electrochemical action, the color of the solution nearly remains unchanged.

(25) In order to further illustrate the technological advancement of the present invention, the following comparative examples are supplemented:

Comparative Example 1

(26) The technical solution is basically the same as the above embodiments, and the composition of the iron-based amorphous alloy is Fe.sub.78Si.sub.8B.sub.14 (at. %), wherein the differences is that the present example does not apply current and voltage, and the remaining technical details are the same as the above embodiments. The test results show that it takes 120 min to effectively degrade the azo dye, and the decolorizing efficiency is 96.09%. Obviously, by comparison, it can be found that the decoloring effect of the technical solution of the present invention is greatly enhanced.

Comparative Example 2

(27) The reaction is performed by utilizing a high-purity iron foil and an iron-based amorphous alloy Fe.sub.78Si.sub.8B.sub.14 (at. %) ribbon as the electrodes, the voltages are 0.5V, and the other experimental conditions are the same. When the reaction time is 120 min and the high-purity iron foil is used as the electrode, the degradation efficiency of the acidic orange II solution can reach 98.06%, the electric energy consumption is 91.65 J, the electric energy consumption per unit degradation efficiency is 0.94 J/%, and the mass loss of the electrode is 60 mg; When the iron-based amorphous alloy Fe.sub.78Si.sub.8B.sub.14 (at. %) ribbon is used as the electrode, the degradation efficiency of the acidic orange II solution can reach 98.35%, the electrical energy consumption per unit degradation efficiency is 0.66 J/%, and the mass loss of the electrode is 21 mg. It can be seen that compared with the high-purity iron foil, when the iron-based amorphous alloy ribbon is used as an electrode for electrochemically degrading the acidic orange II solution, it has the advantages of high degradation efficiency, low electrode loss, long electrode life and low electric energy consumption.

(28) The above embodiments are only intended to illustrate the technical concept and the features of the present invention, and the purpose of the present invention is to enable those skilled in the art to understand the contents of the present invention and to implement the present invention. Equivalent changes or modifications made in accordance with the spirit of the invention are intended to be included within the scope of the invention.