Photocatalytic electrode responding to visible lights and application thereof on chromium-containing wastewater treatment

A photocatalysis and visible light technology, applied in the field of advanced oxidation technology and water treatment, can solve the problem of high probability of photo-generated electrons and holes recombination, and achieve the effect of inhibiting electron-hole recombination, saving operating costs and having broad application prospects.

Inactive Publication Date: 2014-05-28
ZHEJIANG GONGSHANG UNIVERSITY
View PDF5 Cites 23 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the recombination probability of photogenerated electrons and holes generated after excitation by visible light is very high, Bi 2 o 3 The visible light photocatalytic activity still cannot meet the requirements of practical application and needs to be further improved.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Photocatalytic electrode responding to visible lights and application thereof on chromium-containing wastewater treatment
  • Photocatalytic electrode responding to visible lights and application thereof on chromium-containing wastewater treatment
  • Photocatalytic electrode responding to visible lights and application thereof on chromium-containing wastewater treatment

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0046] In AgI / TiO 2 Bi loading during the preparation of -NTs 2 o 3 , by comparing AgI / TiO 2 -NTs, Bi 2 o 3 / TiO 2 -NTs and Bi 2 o 3 / AgI / TiO 2 Hexavalent chromium removal rate constant of -NTs, investigation of AgI and Bi 2 o 3 Whether there is a synergistic effect.

[0047] From figure 1 It can be seen that under the applied bias voltage of 2V, using Bi 2 o 3 / AgI / TiO 2 - The removal rate constant of hexavalent chromium in the reactor of the NTs electrode is significantly higher than that of AgI / TiO 2 -NTs and Bi 2 o 3 / TiO 2 - The sum of the removal rate constants at the NTs electrode. Visible, for TiO 2 -Diversified modification of NTs electrodes can improve catalytic efficiency, Bi 2 o 3 The synergistic effect with AgI is obvious, which makes the separation of photogenerated charges easier.

Embodiment 2

[0049] Study on Calcination Temperature Treatment vs Bi 2 o 3 / AgI / TiO 2 -The effect of photocatalytic degradation of Cr(VI) by NTs under visible light (λ﹥420nm), at pH 3, Cr(VI) concentration is 8×10 -5 Under the reaction conditions of mol / L, the concentration of Cr(VI) in each reactor with photocatalysts calcined at 0°C, 100°C, 200°C, 350°C, and 500°C was calculated respectively when the reaction reached 70 minutes. Determination.

[0050] From figure 2 Compared with no calcination treatment, the calcination treatment effectively increased the Bi 2 o 3 / AgI / TiO 2 - the photocatalytic performance of NTs, and when the calcination temperature is 350 °C, the Bi 2 o 3 / AgI / TiO 2 The removal rate of -NTs to Cr(VI) reaches the maximum and the effect is the best.

Embodiment 3

[0052] To study the effect of different applied bias voltages on Bi 2 o 3 / AgI / TiO 2 -Influence of photocatalytic reduction of Cr(VI) by NTs-350℃ under visible light (λ>420nm), at pH 3, Cr(VI) concentration is 8×10 -5 Under the reaction conditions of mol / L, the applied bias voltages of each reactor were 0.5V, 1V, 1.5V, 2V and 2.5V, respectively. The concentration of Cr(VI) in each reactor was measured when the reaction was carried out to 70min.

[0053] From image 3 It can be seen that the concentration of Cr(VI) decreases with the increase of the applied bias voltage. It can be seen that the applied bias voltage is one of the important factors affecting the photocatalytic efficiency, and it can be known from reasonable speculation that within a certain range, with the The increase of Cr(VI) removal rate showed an upward trend.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a photocatalytic electrode responding to visible lights and an application thereof on chromium-containing wastewater treatment. The preparation method of the photocatalytic electrode comprises the following steps: impregnating a TiO2-NTs electrode in a KI solution for 2 to 2.5 hours, taking out the TiO2-NTs electrode, impregnating the TiO2-NTs electrode in an AgNO3 solution with a pH value of 10.5 to 11.5 for 2 to 2.5 hours, washing the prepared electrode with deionized water, drying in the air, then soaking the electrode in a Bi(NO3)3 solution for 0.5 to 1 hour, taking out the electrode, drying in the air, and calcinating the electrode in a muffle furnace for 2 to 2.5 hours so as to obtain the Bi2O3/AgI/TiO2-NTs electrode. The application of the electrode on a chromium-containing wastewater treatment comprises the following steps: adding wastewater containing hexavalent chromium into a reactor taking the Bi2O3/AgI/TiO2-NTs electrode as the work electrode and Pt as the counter electrode, adjusting the reaction pH value by using an inorganic acid, stirring in the absence of light so as to ensure the absorption balance on the electrodes, applying a work voltage, and starting a light source to irradiate the system so as to carry out reactions. A photocatalytic electrode responding to visible lights is utilized, at the same time a certain amount of anode deflecting voltage is applied on the electrode so as to treat Cr(VI) through a photoelectric synergetic effect, and the treatment has the advantages of good treatment effect, rapid speed, and low cost.

Description

technical field [0001] The invention relates to the fields of advanced oxidation technology and water treatment technology, in particular to the use of a visible light responsive photocatalytic electrode Bi 2 o 3 / AgI / TiO 2 A method for photocatalytic treatment of chromium-containing wastewater by NTs. Background technique [0002] The heavy metal chromium (Cr(VI)) is a common pollutant in the wastewater of electroplating, tanning and printing and dyeing industries. It has strong teratogenicity and carcinogenicity. my country's key control object. At present, the idea of ​​chromium pollution control is to reduce hexavalent chromium Cr(VI) with good solubility, easy migration and high toxicity to trivalent chromium Cr(III) which is 100 times less toxic and easy to coordinate and precipitate. [0003] As an emerging sewage advanced treatment technology, photoelectrocatalytic technology has the following advantages compared with photocatalytic technology: on the one hand, be...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C02F1/467C02F101/22
CPCY02W10/37
Inventor 余可儿许剑佳邹钢郭丝丝俞柯军许媛媛王齐
Owner ZHEJIANG GONGSHANG UNIVERSITY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap