阅读说明：本技术 一种室温冷热交替下处理染料污水的热释电催化剂及其制备方法和应用 (Pyroelectric catalyst for treating dye sewage at room temperature under alternating cold and heat, and preparation method and application thereof ) 是由 胡长征 孙朝中 季瑞 郭晓莹 方亮 于 2020-03-20 设计创作，主要内容包括：本发明公开了一种室温冷热交替下处理染料污水的热释电催化剂及其制备方法和应用。将高纯碳酸钡、碳酸钠、五氧化二铌和五氧化二钽,根据名义化学式Ba<Sub>4</Sub>Na<Sub>2</Sub>Nb<Sub>4</Sub>Ta<Sub>6</Sub>O<Sub>30</Sub>(BNNT)按化学计量比配料,经一次球磨、干燥、压柱、预烧、二次球磨等工序,利用高温固相反应,最终产物经高能球磨制得BNNT亚微米粉体。在经过25～50℃冷热交替循环30次后,染料罗丹明B的降解率在99％以上。该方法制作成本低,制备简单,适合规模化工业化生产,对染料罗丹明B具有极佳的降解效果,对于治理染料污水降解方面具有重要意义。(The invention discloses a pyroelectric catalyst for treating dye sewage at room temperature under alternating cold and heat, and a preparation method and application thereof. High-purity barium carbonate, sodium carbonate, niobium pentoxide and tantalum pentoxide are mixed according to a nominal chemical formula Ba 4 Na 2 Nb 4 Ta 6 O 30 (BNNT) burdening according to the stoichiometric ratio, carrying out the procedures of primary ball milling, drying, column pressing, presintering, secondary ball milling and the like, utilizing high-temperature solid phase reaction, and carrying out high-energy ball milling on the final product to prepare BNNT submicron powder. After cold and hot circulation is carried out for 30 times at 25-50 ℃,the degradation rate of the dye rhodamine B is more than 99 percent. The method is low in manufacturing cost, simple in preparation, suitable for large-scale industrial production, has an excellent degradation effect on dye rhodamine B, and has important significance in the aspect of treating dye sewage degradation.)

1. A pyroelectric catalyst for treating dye sewage at room temperature by alternating cold and heat is characterized in that the nominal chemical formula of the pyroelectric catalyst is Ba₄Na₂Nb₄Ta₆O₃₀。

2. The preparation method of the pyroelectric catalyst according to claim 1, characterized by comprising the following specific steps:

(1) BaCO with purity of more than 99.9 percent₃、Na₂CO₃、Nb₂O₅And Ta₂O₅As starting material, according to BaCO₃:Na₂CO₃:Nb₂O₅:Ta₂O₅Mixing the materials according to the molar ratio of 4:1:2:3, then using absolute ethyl alcohol as a ball milling medium, mixing and ball milling for 24 hours, and finally obtaining the productDrying for 4 hours at 100 ℃ to prepare a dried sample;

(2) pre-sintering the dried sample prepared in the step (1) at 1000-1200 ℃ for 4 hours to prepare a pre-sintered column body;

(3) putting the pre-sintered column body prepared in the step (2) into an agate mortar to be ground into powder, then using absolute ethyl alcohol as a ball milling medium to perform ball milling for 24 hours, uniformly mixing, drying for 4 hours at 100 ℃, then grinding into powder, pressing the column, sintering for 4-10 hours at 1400-1550 ℃ in the air atmosphere of a high-temperature furnace, then naturally cooling to room temperature along with the furnace, finally grinding the sample into powder, putting the sample into a high-energy ball mill, using absolute ethyl alcohol as a ball milling medium to perform ball milling for 24 hours, drying for 4 hours at 100 ℃, and then grinding into powder, thus obtaining Ba₄Na₂Nb₄Ta₆O₃₀The catalyst powder of (3).

3. The preparation method according to claim 2, wherein the pyroelectric catalyst is prepared from high-purity barium carbonate, sodium carbonate, niobium pentoxide and tantalum pentoxide.

4. Ba of claim 2₄Na₂Nb₄Ta₆O₃₀The preparation method of the pyroelectric catalyst is characterized in that Ba is prepared₄Na₂Nb₄Ta₆O₃₀The catalyst powder is prepared by ball milling zirconium dioxide with a ball diameter of 0.5mm and anhydrous ethanol as a ball milling medium for 24-48 h in a zirconium dioxide ceramic ball milling tank at a rotating speed of 300-350 r/min.

5. The pyroelectric catalyst of claim 1 is used for degrading rhodamine B dye sewage.

6. Use of the pyroelectric catalyst according to claim 5, characterized in that: the catalyst is used for degrading dye rhodamine B under the cold-hot circulation at 25-50 ℃, and the catalytic efficiency is 99%.

Technical Field

The invention belongs to the field of sewage treatment, relates to a method for degrading dye sewage by adopting a pyroelectric catalyst, and particularly relates to a tungsten bronze structure Ba₄Na₂Nb₄Ta₆O₃₀A method for degrading rhodamine B dye sewage by using a pyroelectric catalyst.

Background

The dye is used as an important chemical raw material and is closely related to human clothes and eating habits. But a large amount of dye sewage is generated in the production and use processes of the dye, and the sewage has the characteristics of large water quantity, complex components, deep chroma, difficult degradation and the like. And most dyes have toxicity and carcinogenicity, and seriously affect the natural environment. Effective treatment of dye sewage is a difficult problem in industry development. However, the traditional biochemical treatment of dye sewage has high operation cost and more byproducts, which easily cause secondary pollution of water. Although the photocatalytic treatment degradation is a clean and green sewage treatment method, the photocatalytic efficiency is low, and the actual application of the photocatalytic treatment degradation is restricted due to insufficient response force in a dark environment. Therefore, the method for degrading the dye sewage with green color and high catalytic efficiency is of great significance.

Disclosure of Invention

The nominal chemical formula of the pyroelectric catalyst is Ba₄Na₂Nb₄Ta₆O₃₀。

In order to realize the purpose, the invention provides a method for degrading dye sewage by alternately cooling and heating at room temperature, which has high degradation efficiency, low production cost and simple treatment. The principle is that the interior of the catalyst is polarized through the change of the environmental temperature, polarization charges appear on the surface of the material macroscopically, and the charges are combined with oxygen and hydroxide ions in dye sewage to generate active particles with strong oxidizing property, so that the organic dye is oxidized and degraded, and the principle is shown in figure 1.

Based on the research, the method is applied to the specific process that 50mg of BNNT submicron powder is added into 50m L rhodamine B solution (the concentration is 5-15 mg/L), degradation is carried out under the condition of cold and hot circulation at the temperature of 25-50 ℃, circulation is carried out for 6-30 times, centrifugal separation is carried out, the ultraviolet absorbance of the dye rhodamine B before and after degradation is measured, and the degradation rate of the dye is calculated.

The invention has the following advantages: (1) the invention adopts the traditional solid phase method to prepare and uses the high-energy ball mill to prepare the BNNT submicron powder, so that the treatment cost is low, the industrial production is convenient, and the application prospect is wide. (2) The degradation condition is simple, and only room temperature cold-hot circulation is needed. And (3) the method has good decolorizing effect when being used for treating dye wastewater, and the efficiency of degrading dye rhodamine B is up to more than 99%. (4) Is environment-friendly and does not cause secondary pollution to water.

Drawings

FIG. 1 shows Ba prepared in an example of the present invention₄Na₂Nb₄Ta₆O₃₀The catalytic principle of the pyroelectric catalyst is shown schematically.

FIG. 2 shows Ba prepared according to an embodiment of the present invention₄Na₂Nb₄Ta₆O₃₀X-ray spectra of the pyroelectric catalysts.

FIG. 3 shows Ba prepared according to an embodiment of the present invention₄Na₂Nb₄Ta₆O₃₀Surface microtopography photo of pyroelectric catalyst.

FIG. 4 shows Ba prepared by an example of the present invention₄Na₂Nb₄Ta₆O₃₀Size distribution of the pyroelectric catalyst particles.

FIG. 5 shows Ba prepared according to an embodiment of the present invention₄Na₂Nb₄Ta₆O₃₀And an ultraviolet-visible absorption spectrum data graph of the 5 mg/L rhodamine B dye solution degraded by the pyroelectric catalyst after different thermal cycle times (from 25-50 ℃), wherein an inset shows a cold-heat cycle curve.

FIG. 6 shows Ba prepared according to an embodiment of the present invention₄Na₂Nb₄Ta₆O₃₀The degradation efficiency of the pyroelectric catalyst for degrading the RhB dye by thermal cycle times (25-50 ℃) is compared with that of the RhB dye degraded by thermal catalysis without BNNT.

Detailed Description