CN-121990675-A - Preparation of graphene loaded nano zero-valent iron and application of graphene loaded nano zero-valent iron in chromium-containing wastewater treatment

Abstract

The invention relates to preparation of graphene loaded nano zero-valent iron and application thereof in chromium-containing wastewater treatment, comprising the following steps of preparing 60mL of KBH 4 solution with the concentration of 0.5 mol/L as A solution, 60mL of FeSO 4 ·7H 2 O solution with the concentration of 0.1 mol/L as B solution, adding 0.25g of single-layer graphene oxide dispersion liquid into the B solution, stirring for 30min, marking the C solution as C solution, slowly dripping the A solution into the C solution, carrying out suction filtration and separation on the powder C, and drying to obtain nZVI@GO. According to the invention, after the graphene is loaded with the nZVI, the chromium in the chromium-containing wastewater is adsorbed, and the nZVI@GO@Cr formed after wastewater treatment can be used as an auxiliary tanning agent for leather tanning or retanning sections, so that the method has good recyclability.

Inventors

• TANG JINLU
• CHEN YIPENG
• XU WENJIAN
• LIU LIN
• PAN DANDAN
• WEN HUITAO

Assignees

• 兴业皮革科技股份有限公司

Dates

Publication Date

20260508

Application Date

20251229

Claims (2)

1. 1. The preparation method of the graphene loaded nano zero-valent iron is characterized by comprising the following steps of: Step 1, preparing 60mL of KBH 4 solution with the concentration of 0.5 mol/L as a solution A, and 60mL of FeSO 4 ·7H 2 O solution with the concentration of 0.1 mol/L as a solution B; step 2, adding 0.25g of single-layer graphene oxide dispersion liquid into the solution B under magnetic stirring, and stirring for 30min to obtain solution C; Step 3, slowly dripping the solution A into the solution C, and keeping the reaction temperature at 23-28 ℃; Step 4, stirring for 30min continuously, and changing the solution from light green to black to generate black powder C; and 5, carrying out suction filtration and separation on the powder C, alternately washing with ethanol and water for three times, and drying to obtain graphene loaded nano zero-valent iron, and marking the graphene loaded nano zero-valent iron as powder D.
2. 2. The application of graphene loaded nano zero-valent iron in chromium-containing wastewater treatment according to claim 1, wherein the pH value of the chromium-containing wastewater is adjusted to 3.5-4, 500mg of powder D is added into 1000mL of chromium-containing wastewater, and the powder D is vibrated for 30-120min at the temperature of 25-30 ℃ to complete the treatment of the chromium-containing wastewater by nZVI.

Description

Preparation of graphene loaded nano zero-valent iron and application of graphene loaded nano zero-valent iron in chromium-containing wastewater treatment Technical Field The invention relates to the technical field of chromium-containing wastewater treatment, in particular to preparation of graphene loaded nano zero-valent iron and application of the graphene loaded nano zero-valent iron in chromium-containing wastewater treatment. Background Chromium-containing wastewater is a typical characteristic pollutant discharged in the industrial production processes of electroplating, tanning, printing and dyeing and the like, wherein chromium element, especially hexavalent chromium (Cr 6+), has high toxicity, strong carcinogenicity and good environment mobility, and has serious potential threat to the ecological system and human health, namely hexavalent chromium can be enriched step by step through a food chain, and long-term exposure can cause health damage such as gene mutation, organ damage and the like, even malignant tumor. With the increasing strictness of environmental regulations, the efficient and compliant treatment of chromium-containing wastewater has become a key issue in the field of industrial pollution control. At present, the treatment means for chromium-containing wastewater in the field mainly comprise a chemical precipitation method, an adsorption method, an ion exchange method and a biological reduction method, but the methods have the common technical defects: 1. the chemical precipitation method has simple operation flow, but is easy to produce a large amount of chromium-containing dangerous sludge, and the subsequent sludge treatment is easy to cause secondary pollution risk; 2. The adsorption method is that the regeneration performance of the adsorbent is poor, so that the treatment cost is high, and the concentration of the chromium in the effluent is difficult to be stably controlled below the limit value of 0.5mg/L specified in the integrated wastewater discharge Standard (GB 8978-1996); 3. the ion exchange method has the problems of easy poisoning and deactivation of resin, complex operation and maintenance flow and the like; 4. The biological reduction method is limited by microorganism growth conditions (such as temperature and pH), the treatment efficiency is easy to fluctuate, and the large-scale industrial application difficulty is high. Along with the strict environmental protection supervision and the wide popularization of the green manufacturing concept, the field is urgently required to develop a novel chromium-containing wastewater chromium removal technology with high treatment efficiency, low operation cost and good effluent stability so as to meet the actual requirements of industrial wastewater on standard emission and recycling. Disclosure of Invention The invention provides a preparation method of graphene loaded nano zero-valent iron and application of the graphene loaded nano zero-valent iron in chromium-containing wastewater treatment, so as to solve the problems in the existing chromium-containing wastewater treatment. The invention adopts the following technical scheme: the preparation method of the graphene loaded nano zero-valent iron comprises the following steps: Step 1, preparing 60mL of KBH 4 solution with the concentration of 0.5 mol/L as a solution A, and 60mL of FeSO 4·7H2 O solution with the concentration of 0.1 mol/L as a solution B; Under the magnetic stirring, adding 0.25g of single-layer graphene oxide dispersion liquid (average radial dimension: 5-8 μm, thickness: 1nm,2mg/mL, dispersion in H 2 O, shanghai Michelin Biochemical technologies Co., ltd.) into the solution B, stirring for 30min, and recording as solution C; Step 3, slowly dripping the solution A into the solution C, and keeping the reaction temperature at 23-28 ℃; Step 4, stirring for 30min continuously, and changing the solution from light green to black to generate black powder C; and 5, carrying out suction filtration and separation on the powder C, alternately washing with ethanol and water for three times, and drying to obtain graphene loaded nano zero-valent iron (nZVI@GO), which is marked as powder D. The application of graphene loaded nano zero-valent iron in chromium-containing wastewater treatment is that the pH of the chromium-containing wastewater is regulated to 3.5-4, 500mg of powder D is added into 1000mL of chromium-containing wastewater, and oscillation is carried out for 30-120min at the temperature of 25-30 ℃ to finish the treatment of nZVI on the chromium-containing wastewater. As can be seen from the above description of the structure of the present invention, compared with the prior art, the present invention has the following advantages: 1. The nZVI prepared by adopting the chemical reduction method is easy to agglomerate, the specific surface area of the nZVI can be reduced, and the chromium removal rate is affected; Graphene (GO) is used as a functional material