Hydrothermal preparation method of nano-ZnO cellulose composite material on basis of NaOH-urea solution and application

Abstract

The invention discloses a hydrothermal preparation method of a nano-ZnO cellulose composite material on the basis of a NaOH-urea solution and application. The method comprises the step that in the NaOH-urea cellulose solution, the nano-ZnO cellulose composite material is prepared through in-situ compounding by adopting the hydrothermal method. According to the hydrothermal preparation method of the nano-ZnO cellulose composite material on the basis of the NaOH-urea solution, after cellulose is dissolved, hydroxyl groups on molecules of the cellulose are combined with zinc ions, and the defect that a zinc source does not easily penetrate into a carrier is overcome; in addition, the adopted NaOH-urea solvent is cheap and easy to obtain, and the hydrothermal synthesis temperature is obviously reduced. The nano-ZnO cellulose composite material contains 47.5% of ZnO and has the high removal efficiency on phenol in photodegradation wastewater. The ZnO cellulose composite material prepared through the method is cheap and environmentally friendly and has the very good practicability on phenolic wastewater treatment by serving as a photodegradation catalyst.

Description

technical field

[0001] The invention belongs to the technical field of nano ZnO cellulose composite materials, and in particular relates to a hydrothermal preparation method and application of nano ZnO cellulose composite materials based on NaOH / urea solution. Background technique

[0002] Zinc oxide (ZnO) is a unique wide bandgap direct bandgap semiconductor oxide with a bandgap of 3.37eV at room temperature. Its wide bandgap, high breakdown strength and saturated electron mobility make it have excellent It is widely used in photoanode materials of solar cells and high-performance transistors and other fields. Due to its nano-effects, ZnO nanomaterials have been greatly improved in terms of mechanical, photoelectric, piezoelectric, gas-sensing, and catalytic properties, and have shown some new physical properties, such as good photocatalytic performance, excellent field Emission properties, superior wave-absorbing properties, and good doped dilute magnetism, etc. These pro...

Examples

Embodiment 1Z

[0026] The preparation of embodiment 1ZnO cellulose nanocomposite material (zinc acetate is zinc source)

[0027] Take 50g of NaOH / Urea aqueous solution (NaOH:Urea:H 2 The mass ratio of O is 7︰12︰81), add 2g of microcrystalline cellulose, stir rapidly until dissolved, add dropwise 30mL of 1mol / L Zn(CH 3 COO) 2 solution, after stirring and aging for 30min, with 2% H 2 SO 4 The pH value of the solution was adjusted to 9, transferred to a hydrothermal reaction kettle for 2 hours at 100°C, washed with distilled water for 3 times, dried in an oven at 70°C, and weighed to obtain a nano-ZnO cellulose composite material.

[0028] The prepared ZnO cellulose nanocomposites were characterized as follows:

[0029] Electron microscope images of the prepared ZnO cellulose nanocomposites figure 1 As shown, the infrared image is shown as figure 2 As shown, TG as image 3 As shown, the XRD pattern is as Figure 4 . It can be seen from the electron microscope that ZnO gathers on the s...

Embodiment 2Z

[0030] Photodegradation performance of embodiment 2 ZnO cellulose nanocomposites to phenol wastewater

[0031] Get the phenol solution of 100mL 50mg / L in the 250mL quartz beaker, add the ZnO / cellulose composite material 0.1g that obtains in the embodiment 1, add the hydrogen peroxide of 0.01g30% after stirring on the magnetic stirrer, under ultraviolet light and Under sunlight, samples were taken every half hour to analyze the concentration of phenol in the solution, and the solution was stirred for 6 hours. After 6 hours, the removal rate of phenol was 66.36%.

[0032] The concentration of phenol was obtained by measuring the absorbance at 235 nm with a UV-visible spectrophotometer according to the phenol standard curve.

[0033] The formula for calculating the removal rate of phenol is:

[0034] In the formula, C 0 and C are the concentration of phenol solution before and after photodegradation respectively;

[0035] The removal rate of phenol is as follows Figure 5 s...

Embodiment 3

[0037] Take 50g of NaOH / Urea aqueous solution (NaOH:Urea:H 2 The mass ratio of O is 7︰12︰81), add 4g microcrystalline cellulose, stir rapidly until dissolved, add 1mol / L ZnCl dropwise 2 , after stirring and aging for 30min, with 2% H2 SO 4 The pH value of the solution was adjusted to 9, transferred to a hydrothermal reaction kettle for 2 hours at 100°C, washed with distilled water for 3 times, dried in an oven at 70°C, and weighed to obtain a nano-ZnO cellulose composite material.

[0038] Electron microscope images of the prepared ZnO cellulose nanocomposites Image 6 As shown, the infrared image is shown as Figure 7 As shown, the XRD pattern is as Figure 8 shown, from Image 6 It can be seen that due to the addition of more cellulose, the cellulose dissolution is not sufficient, and some cellulose microfibrils exist, and the generated ZnO is wrapped on the surface of the cellulose microfibrils. The dissolved and regenerated cellulose particles are small, and fluffy Zn...

technical field

[0001] The invention belongs to the technical field of nano ZnO cellulose composite materials, and in particular relates to a hydrothermal preparation method and application of nano ZnO cellulose composite materials based on NaOH / urea solution. Background technique

[0002] Zinc oxide (ZnO) is a unique wide bandgap direct bandgap semiconductor oxide with a bandgap of 3.37eV at room temperature. Its wide bandgap, high breakdown strength and saturated electron mobility make it have excellent It is widely used in photoanode materials of solar cells and high-performance transistors and other fields. Due to its nano-effects, ZnO nanomaterials have been greatly improved in terms of mechanical, photoelectric, piezoelectric, gas-sensing, and catalytic properties, and have shown some new physical properties, such as good photocatalytic performance, excellent field Emission properties, superior wave-absorbing properties, and good doped dilute magnetism, etc. These pro...

Examples

Embodiment 1Z

[0026] The preparation of embodiment 1ZnO cellulose nanocomposite material (zinc acetate is zinc source)

[0027] Take 50g of NaOH / Urea aqueous solution (NaOH:Urea:H 2 The mass ratio of O is 7︰12︰81), add 2g of microcrystalline cellulose, stir rapidly until dissolved, add dropwise 30mL of 1mol / L Zn(CH 3 COO) 2 solution, after stirring and aging for 30min, with 2% H 2 SO 4 The pH value of the solution was adjusted to 9, transferred to a hydrothermal reaction kettle for 2 hours at 100°C, washed with distilled water for 3 times, dried in an oven at 70°C, and weighed to obtain a nano-ZnO cellulose composite material.

[0028] The prepared ZnO cellulose nanocomposites were characterized as follows:

[0029] Electron microscope images of the prepared ZnO cellulose nanocomposites figure 1 As shown, the infrared image is shown as figure 2 As shown, TG as image 3 As shown, the XRD pattern is as Figure 4 . It can be seen from the electron microscope that ZnO gathers on the s...

Embodiment 2Z

[0030] Photodegradation performance of embodiment 2 ZnO cellulose nanocomposites to phenol wastewater

[0031] Get the phenol solution of 100mL 50mg / L in the 250mL quartz beaker, add the ZnO / cellulose composite material 0.1g that obtains in the embodiment 1, add the hydrogen peroxide of 0.01g30% after stirring on the magnetic stirrer, under ultraviolet light and Under sunlight, samples were taken every half hour to analyze the concentration of phenol in the solution, and the solution was stirred for 6 hours. After 6 hours, the removal rate of phenol was 66.36%.

[0032] The concentration of phenol was obtained by measuring the absorbance at 235 nm with a UV-visible spectrophotometer according to the phenol standard curve.

[0033] The formula for calculating the removal rate of phenol is:

[0034] In the formula, C 0 and C are the concentration of phenol solution before and after photodegradation respectively;

[0035] The removal rate of phenol is as follows Figure 5 s...

Embodiment 3

[0037] Take 50g of NaOH / Urea aqueous solution (NaOH:Urea:H 2 The mass ratio of O is 7︰12︰81), add 4g microcrystalline cellulose, stir rapidly until dissolved, add 1mol / L ZnCl dropwise 2 , after stirring and aging for 30min, with 2% H2 SO 4 The pH value of the solution was adjusted to 9, transferred to a hydrothermal reaction kettle for 2 hours at 100°C, washed with distilled water for 3 times, dried in an oven at 70°C, and weighed to obtain a nano-ZnO cellulose composite material.

[0038] Electron microscope images of the prepared ZnO cellulose nanocomposites Image 6 As shown, the infrared image is shown as Figure 7 As shown, the XRD pattern is as Figure 8 shown, from Image 6 It can be seen that due to the addition of more cellulose, the cellulose dissolution is not sufficient, and some cellulose microfibrils exist, and the generated ZnO is wrapped on the surface of the cellulose microfibrils. The dissolved and regenerated cellulose particles are small, and fluffy Zn...

Images