Application of Sr-Ni-Cr co-doped LaAlO<3> photocatalyst in treatment of organic wastewater

Abstract

The invention relates to an application of a Sr-Ni-Cr co-doped LaAlO<3> photocatalyst in treatment of organic wastewater. The photocatalyst is prepared according to a stoichiometric ratio as shown ina chemical formula of LaSrNi<c>Al<d>Cr<e>O<3>, wherein a is in a range of 0.7 to 0.9, b is in a range of 0.05 to 0.15, c is in a range of 0.05 to 0.15, d is in a range of 0.7 to 0.9 and e is ina range of 1 to 0.3. A preparation method for the photocatalyst comprises the following steps: weighing strontium nitrate, nickel nitrate, chromium nitrate, lanthanum nitrate and aluminum nitrate, dissolving the weighed substances in water, then adding a certain amount of urea, conducting ultrasonic dispersion, performing microwave heating, carrying out drying and roasting, performing grinding andcompression molding, carrying out calcining for a period of time, and carrying out grinding again so as to obtain the photocatalyst with a forbidden band width of 1.31-1.35 eV. The photocatalyst hasthe advantages that organic pollutants in organic wastewater can be efficiently degraded under the condition of visible light, repeatability is good, secondary pollution cannot be caused and the photocatalyst can be widely used; and the photocatalyst has very good practical application prospects.

Description

[0001] 1.1.1 Technical field

[0002] The invention belongs to the field of organic wastewater treatment, in particular to a method of co-doping LaAlO with Sr, Ni and Cr 3 Application of photocatalysts in organic wastewater treatment.

[0003] 1.1.2 Background technology

[0004] At present, the problem of environmental pollution has become one of the focal issues of global concern. The quality of the environment seriously affects people's living standards and the sustainable development of society. The development and utilization of photocatalytic technology is one of the effective ways to solve the problem of environmental pollution.

[0005] LaAlO 3 It is a perovskite-type semiconductor, and it is a new photocatalyst with low price, stable chemical properties and non-toxic and harmless to the environment. Its band gap is 3.23eV, and it has no response under visible light. while for LaAlO 3 Ion doping to reduce its forbidden band width and make it correspondingly under vi...

Examples

preparation example Construction

[0027] A kind of Sr, Ni and Cr co-doped LaAlO provided by the invention 3 The preparation method of photocatalyst comprises the following steps:

[0028] 1) According to the chemical formula La a Sr b Ni c Al d Cr e o 3 stoichiometric ratio, wherein a=0.7~0.9, b=0.05~0.15, c=0.05~0.15, d=0.7~0.9, e=0.1~0.3, weigh strontium nitrate, nickel nitrate, chromium nitrate, lanthanum nitrate and Put aluminum nitrate into a beaker, add appropriate amount of distilled water and stir to dissolve;

[0029] 2) Add urea 1 to 1.5 times the total molar amount of metal ions to the beaker under stirring conditions, ultrasonically disperse for 1 to 3 hours, then microwave in a microwave chemical reactor at 70 to 90°C for 1 to 3 hours, and evaporate to obtain intermediate Product A;

[0030] 3) Put product A in a drying oven at 100-140°C and dry for 10-16 hours, then grind the dried sample, then put it in a muffle furnace and bake it at 1100-1300°C for 1-3 hours, take out the sample and wa...

Embodiment 1

[0036] A Sr, Ni and Cr co-doped LaAlO 3The preparation method of photocatalyst comprises the following steps:

[0037] 1) According to the chemical formula La a Sr b Ni c Al d Cr e o 3 stoichiometric ratio, where a=0.8, b=0.1, c=0.1, d=0.8, e=0.2, weigh strontium nitrate, nickel nitrate, chromium nitrate, lanthanum nitrate and aluminum nitrate into a beaker, add an appropriate amount of Distilled water was stirred thoroughly to dissolve;

[0038] 2) Add urea 1.5 times the total molar amount of metal ions to the beaker under stirring conditions, ultrasonically disperse for 2 hours, then heat in microwave at 85°C for 2 hours in a microwave chemical reactor, and evaporate to obtain intermediate product A;

[0039] 3) Put the product A in a drying oven at 120°C for 14 hours, then grind the dried sample, then put it into a muffle furnace and bake it at 1250°C for 2 hours, take out the sample and wait for it to cool to room temperature before fully grinding to obtain a loose ...

Embodiment 2

[0042] A Sr, Ni and Cr co-doped LaAlO 3 The preparation method of photocatalyst comprises the following steps:

[0043] 1) According to the chemical formula La a Sr b Ni c Al d Cr e o 3 stoichiometric ratio, where a=0.8, b=0.15, c=0.05, d=085, e=0.15, weigh strontium nitrate, nickel nitrate, chromium nitrate, lanthanum nitrate and aluminum nitrate into a beaker, add an appropriate amount of Distilled water was stirred thoroughly to dissolve;

[0044] 2) Add urea 1 times the total molar amount of metal ions to the beaker under stirring conditions, ultrasonically disperse for 3 hours, then heat in a microwave chemical reactor at 75°C for 3 hours, and evaporate to obtain intermediate product A;

[0045] 3) Put product A in a drying oven at 100°C for 16 hours, then grind the dried sample, then put it into a muffle furnace and bake it at 1300°C for 1 hour, take out the sample and wait for it to cool to room temperature before fully grinding to obtain a loose powder;

[004...

[0001] 1.1.1 Technical field

[0002] The invention belongs to the field of organic wastewater treatment, in particular to a method of co-doping LaAlO with Sr, Ni and Cr 3 Application of photocatalysts in organic wastewater treatment.

[0003] 1.1.2 Background technology

[0004] At present, the problem of environmental pollution has become one of the focal issues of global concern. The quality of the environment seriously affects people's living standards and the sustainable development of society. The development and utilization of photocatalytic technology is one of the effective ways to solve the problem of environmental pollution.

[0005] LaAlO 3 It is a perovskite-type semiconductor, and it is a new photocatalyst with low price, stable chemical properties and non-toxic and harmless to the environment. Its band gap is 3.23eV, and it has no response under visible light. while for LaAlO 3 Ion doping to reduce its forbidden band width and make it correspondingly under vi...

Examples

preparation example Construction

[0027] A kind of Sr, Ni and Cr co-doped LaAlO provided by the invention 3 The preparation method of photocatalyst comprises the following steps:

[0028] 1) According to the chemical formula La a Sr b Ni c Al d Cr e o 3 stoichiometric ratio, wherein a=0.7~0.9, b=0.05~0.15, c=0.05~0.15, d=0.7~0.9, e=0.1~0.3, weigh strontium nitrate, nickel nitrate, chromium nitrate, lanthanum nitrate and Put aluminum nitrate into a beaker, add appropriate amount of distilled water and stir to dissolve;

[0029] 2) Add urea 1 to 1.5 times the total molar amount of metal ions to the beaker under stirring conditions, ultrasonically disperse for 1 to 3 hours, then microwave in a microwave chemical reactor at 70 to 90°C for 1 to 3 hours, and evaporate to obtain intermediate Product A;

[0030] 3) Put product A in a drying oven at 100-140°C and dry for 10-16 hours, then grind the dried sample, then put it in a muffle furnace and bake it at 1100-1300°C for 1-3 hours, take out the sample and wa...

Embodiment 1

[0036] A Sr, Ni and Cr co-doped LaAlO 3The preparation method of photocatalyst comprises the following steps:

[0037] 1) According to the chemical formula La a Sr b Ni c Al d Cr e o 3 stoichiometric ratio, where a=0.8, b=0.1, c=0.1, d=0.8, e=0.2, weigh strontium nitrate, nickel nitrate, chromium nitrate, lanthanum nitrate and aluminum nitrate into a beaker, add an appropriate amount of Distilled water was stirred thoroughly to dissolve;

[0038] 2) Add urea 1.5 times the total molar amount of metal ions to the beaker under stirring conditions, ultrasonically disperse for 2 hours, then heat in microwave at 85°C for 2 hours in a microwave chemical reactor, and evaporate to obtain intermediate product A;

[0039] 3) Put the product A in a drying oven at 120°C for 14 hours, then grind the dried sample, then put it into a muffle furnace and bake it at 1250°C for 2 hours, take out the sample and wait for it to cool to room temperature before fully grinding to obtain a loose ...

Embodiment 2

[0042] A Sr, Ni and Cr co-doped LaAlO 3 The preparation method of photocatalyst comprises the following steps:

[0043] 1) According to the chemical formula La a Sr b Ni c Al d Cr e o 3 stoichiometric ratio, where a=0.8, b=0.15, c=0.05, d=085, e=0.15, weigh strontium nitrate, nickel nitrate, chromium nitrate, lanthanum nitrate and aluminum nitrate into a beaker, add an appropriate amount of Distilled water was stirred thoroughly to dissolve;

[0044] 2) Add urea 1 times the total molar amount of metal ions to the beaker under stirring conditions, ultrasonically disperse for 3 hours, then heat in a microwave chemical reactor at 75°C for 3 hours, and evaporate to obtain intermediate product A;

[0045] 3) Put product A in a drying oven at 100°C for 16 hours, then grind the dried sample, then put it into a muffle furnace and bake it at 1300°C for 1 hour, take out the sample and wait for it to cool to room temperature before fully grinding to obtain a loose powder;

[004...