CN105597746A - Efficient preparation method of automobile exhaust catalyst - Google Patents

Abstract

The invention provides an efficient preparation method of an automobile exhaust catalyst. The method comprises the following steps: anodizing aluminum foil, removing a surface alumina layer in an acid liquid, anodizing the obtained aluminum foil, and corroding the aluminum foil in a phosphoric acid solution to obtain a nano-alumina template; drying the nano-alumina template, and sintering the dried template to obtain a catalyst carrier; mixing CeO2, Y2O3, ZrO2, gamma-Al2O3, adding RhCl3 and PtCl3, and roasting and drying above materials to obtain a powdery catalyst; adding the powdery catalyst to an acid solution, and carrying out ball milling on the obtained material to obtain a catalyst coating liquid; coating the catalyst carrier in a dipping mode, removing the superfluous coating liquid in the coated catalyst carrier, and roasting the obtained catalyst carrier; and roasting the catalyst carrier. Addition of yttrium oxide to CeO2-ZrO2 increases the heat stability and the oxonium ion mobility of the catalyst and improves the redox activity of the catalyst, and the method is simple and effective; and the catalyst has very good heat stability and a large specific surface area.

Description

A kind of preparation method of efficient auto-exhaust catalyst

Technical field

The present invention relates to a kind of preparation method of auto-exhaust catalyst, belong to automobile exhaust pollution thing process field.

Background technology

In recent years, along with the rapid growth of vehicle guaranteeding organic quantity, cause urban air pollution to be on the rise, the polluter such as CO, HC, NOx in vehicle exhaust becomes the main source of urban atmospheric pollution especially, and improving constantly vehicle emission standards becomes inexorable trend.

Metallic honeycomb substrate catalyst has following advantage: thermal capacity is little, thermal conductivity is high, pre-good in thermal property, be easy to the short time heat up reach catalysis light-off temperature, therefore the use of metallic carrier can effectively improve the efficiency of motor vehicle tail gas catalytic purification processing under cold start-up, low speed, idling mode; Have the mechanical strength of higher heat shock resistance and vibrations, life cycle is long and installation is easy. We have started the research of metallic honeycomb substrate catalyst.

Summary of the invention

The invention provides a kind of preparation method of efficient auto-exhaust catalyst.

In order to solve the problems of the technologies described above, the present invention adopts following technical scheme:

A preparation method for efficient auto-exhaust catalyst, is characterized in that, comprises the following steps:

(1) using aluminium foil as anode, graphite is as negative electrode, in the oxalic acid solution of 0.3mol/L, anode alumina foil 4h under the voltage of room temperature and 30-50V, in the H3PO4 of 6wt% and the H2CrO4 mixed solution of 1.8wt%, in the water-bath of 60 DEG C, remove surface oxidation aluminium lamination, in the oxalic acid solution of 0.3mol/L, anode alumina foil 2h under the voltage of room temperature and 30-50V, corrosion oxidation aluminium foil at 30 DEG C of phosphoric acid solutions in 5%, obtains nano-alumina template;

(2) nano-alumina template is carried out to slowly dry processing, put into inert gas at 1150-1250 DEG C, sintering time is 2-5h, obtains catalyst carrier;

(3) raw material of following mass parts is mixed: the ZrO2 of the CeO2 of 1.6-3 part, the Y2O3 of 1-2 part, 0.4-1 part, the γ-Al2O3 of 60-80 part, add RhCl3, the PtCl3 of 4-20 part at 500 DEG C of roasting 2h and 110 DEG C of dry powdered form catalyst that obtain for 2 hours;

(4) powdered form catalyst is mixed by the weight ratio of 1:2-1:4 with water, add acid to make pH value between 3-4, ball milling 8-15h, obtains catalyst-coated liquid;

(5) in the mode of flooding by catalyst carrier hanging, coating liquid unnecessary in the catalyst carrier after hanging is removed, at 100-300 DEG C, dry 20-40min, then put into Muffle furnace in 300-500 DEG C of roasting temperature 20-40min;

(6) repeating step (5) at least one times;

(7) catalyst carrier of step (6) is placed in to Muffle furnace in 350-650 DEG C of roasting 2-7h, and is incubated 8-15h.

Preferably, the water-bath equipment in step (1) adopts LH501-2 thermostat water bath.

Preferably, the anodic oxidation equipment in step (1) adopts YJ32-1 transistor npn npn direct current stabilizer.

Preferably, the treatment temperature of the dry run in step (2) is 150 DEG C, and the time is 2-3h.

Preferably, regulate pH value to adopt HCl solution.

The invention has the beneficial effects as follows: add CeO2-ZrO2 to increase the heat endurance of catalyst and the mobility of oxonium ion yittrium oxide, improved the redox active of catalyst, the cellular aluminium oxide catalyst of nanometer prepared by the present invention, method is simply effective.; There is good heat endurance simultaneously and there is large specific area.

Detailed description of the invention

Embodiment 1:

A preparation method for efficient auto-exhaust catalyst, is characterized in that, comprises the following steps:

(1) using aluminium foil as anode, graphite is as negative electrode, in the oxalic acid solution of 0.3mol/L, in YJ32-1 transistor npn npn direct current stabilizer under the voltage of room temperature and 30V anode alumina foil 4h, in the H2CrO4 mixed solution of the H3PO4 of 6wt% in LH501-2 thermostat water bath and 1.8wt%, in the water-bath of 60 DEG C, remove surface oxidation aluminium lamination, in the oxalic acid solution of 0.3mol/L, anode alumina foil 2h under the voltage of room temperature and 30V, corrosion oxidation aluminium foil at 30 DEG C of phosphoric acid solutions in 5%, obtains nano-alumina template;

(2) nano-alumina template is carried out to slowly dry processing, baking temperature is 150 DEG C, and the time is 2h, puts into inert gas at 1150 DEG C, and sintering time is 2h, obtains catalyst carrier;

(3) raw material of following mass parts is mixed: the CeO2 of 1.6 parts, the Y2O3 of 1 part, the ZrO2 of 0.4 part, the γ-Al2O3 of 60 parts, add RhCl3, the PtCl3 of 4 parts at 500 DEG C of roasting 2h and 110 DEG C of dry powdered form catalyst that obtain for 2 hours;

(4) powdered form catalyst is mixed by the weight ratio of 1:2 with water, add HCl solution to make pH value between 3-4, ball milling 8h, obtains catalyst-coated liquid;

(5) in the mode of flooding by catalyst carrier hanging, coating liquid unnecessary in the catalyst carrier after hanging is removed, at 100 DEG C, dry 20min, then put into Muffle furnace in 300 DEG C of roasting temperature 20min;

(6) repeating step (5) once;

(7) catalyst carrier of step (6) is placed in to Muffle furnace in 350 DEG C of roasting 2h, and is incubated 8h.

Embodiment 2:

A preparation method for efficient auto-exhaust catalyst, is characterized in that, comprises the following steps:

(1) using aluminium foil as anode, graphite is as negative electrode, in the oxalic acid solution of 0.3mol/L, in YJ32-1 transistor npn npn direct current stabilizer under the voltage of room temperature and 40V anode alumina foil 4h, in the H2CrO4 mixed solution of the H3PO4 of 6wt% in LH501-2 thermostat water bath and 1.8wt%, in the water-bath of 60 DEG C, remove surface oxidation aluminium lamination, in the oxalic acid solution of 0.3mol/L, anode alumina foil 2h under the voltage of room temperature and 40V, corrosion oxidation aluminium foil at 30 DEG C of phosphoric acid solutions in 5%, obtains nano-alumina template;

(2) nano-alumina template is carried out to slowly dry processing, baking temperature is 150 DEG C, and the time is 2.5h, puts into inert gas at 1200 DEG C, and sintering time is 3.5h, obtains catalyst carrier;

(3) raw material of following mass parts is mixed: the CeO2 of 2 parts, the Y2O3 of 1.5 parts, the ZrO2 of 0.7 part, the γ-Al2O3 of 70 parts, add RhCl3, the PtCl3 of 12 parts at 500 DEG C of roasting 2h and 110 DEG C of dry powdered form catalyst that obtain for 2 hours;

(4) powdered form catalyst is mixed by the weight ratio of 1:3 with water, add HCl solution to make pH value between 3-4, ball milling 11h, obtains catalyst-coated liquid;

(5) in the mode of flooding by catalyst carrier hanging, coating liquid unnecessary in the catalyst carrier after hanging is removed, at 200 DEG C, dry 30min, then put into Muffle furnace in 400 DEG C of roasting temperature 30min;

(6) repeating step (5) secondary;

(7) catalyst carrier of step (6) is placed in to Muffle furnace in 500 DEG C of roasting 5h, and is incubated 11h.

Embodiment 3:

A preparation method for efficient auto-exhaust catalyst, is characterized in that, comprises the following steps:

(1) using aluminium foil as anode, graphite is as negative electrode, in the oxalic acid solution of 0.3mol/L, in YJ32-1 transistor npn npn direct current stabilizer under the voltage of room temperature and 50V anode alumina foil 4h, in the H2CrO4 mixed solution of the H3PO4 of 6wt% in LH501-2 thermostat water bath and 1.8wt%, in the water-bath of 60 DEG C, remove surface oxidation aluminium lamination, in the oxalic acid solution of 0.3mol/L, anode alumina foil 2h under the voltage of room temperature and 50V, corrosion oxidation aluminium foil at 30 DEG C of phosphoric acid solutions in 5%, obtains nano-alumina template;

(2) nano-alumina template is carried out to slowly dry processing, baking temperature is 150 DEG C, and the time is 3h, puts into inert gas at 1250 DEG C, and sintering time is 5h, obtains catalyst carrier;

(3) raw material of following mass parts is mixed: the CeO2 of 3 parts, the Y2O3 of 2 parts, the ZrO2 of 1 part, the γ-Al2O3 of 80 parts, add RhCl3, the PtCl3 of 20 parts at 500 DEG C of roasting 2h and 110 DEG C of dry powdered form catalyst that obtain for 2 hours;

(4) powdered form catalyst is mixed by the weight ratio of 1:4 with water, add HCl solution to make pH value between 4, ball milling 15h, obtains catalyst-coated liquid;

(5) in the mode of flooding by catalyst carrier hanging, coating liquid unnecessary in the catalyst carrier after hanging is removed, at 100-300 DEG C, dry 40min, then put into Muffle furnace in 500 DEG C of roasting temperature 40min;

(6) repeating step (5) secondary;

(7) catalyst carrier of step (6) is placed in to Muffle furnace in 650 DEG C of roasting 7h, and is incubated 15h.

Claims (6)

1. a preparation method for efficient auto-exhaust catalyst, is characterized in that, comprises the following steps:

(1) using aluminium foil as anode, graphite is as negative electrode, in the oxalic acid solution of 0.3mol/L, anode alumina foil 4h under the voltage of room temperature and 30-50V, in the H3PO4 of 6wt% and the H2CrO4 mixed solution of 1.8wt%, in the water-bath of 60 DEG C, remove surface oxidation aluminium lamination, in the oxalic acid solution of 0.3mol/L, anode alumina foil 2h under the voltage of room temperature and 30-50V, corrosion oxidation aluminium foil at 30 DEG C of phosphoric acid solutions in 5%, obtains nano-alumina template;

(2) nano-alumina template is carried out to slowly dry processing, put into inert gas at 1150-1250 DEG C, sintering time is 2-5h, obtains catalyst carrier;

(3) raw material of following mass parts is mixed: the ZrO2 of the CeO2 of 1.6-3 part, the Y2O3 of 1-2 part, 0.4-1 part, the γ-Al2O3 of 60-80 part, add RhCl3, the PtCl3 of 4-20 part at 500 DEG C of roasting 2h and 110 DEG C of dry powdered form catalyst that obtain for 2 hours;

(4) powdered form catalyst is mixed by the weight ratio of 1:2-1:4 with water, add acid to make pH value between 3-4, ball milling 8-15h, obtains catalyst-coated liquid;

(5) in the mode of flooding by catalyst carrier hanging, coating liquid unnecessary in the catalyst carrier after hanging is removed, at 100-300 DEG C, dry 20-40min, then put into Muffle furnace in 300-500 DEG C of roasting temperature 20-40min;

(6) repeating step (5) at least one times;

(7) catalyst carrier of step (6) is placed in to Muffle furnace in 350-650 DEG C of roasting 2-7h, and is incubated 8-15h.

2. the preparation method of a kind of efficient auto-exhaust catalyst according to claim 1, is characterized in that, the water-bath equipment in step (1) adopts LH501-2 thermostat water bath.

3. the preparation method of a kind of efficient auto-exhaust catalyst according to claim 1, is characterized in that, the anodic oxidation equipment in step (1) adopts YJ32-1 transistor npn npn direct current stabilizer.

4. the preparation method of a kind of efficient auto-exhaust catalyst according to claim 1, is characterized in that, the treatment temperature of the dry run in step (2) is 150 DEG C, and the time is 2-3h.

5. the preparation method of a kind of efficient auto-exhaust catalyst according to claim 1, is characterized in that, regulates pH value to adopt HCl solution.

6. the preparation method of a kind of efficient auto-exhaust catalyst according to claim 1, is characterized in that, comprises the following steps:

(1) using aluminium foil as anode, graphite is as negative electrode, in the oxalic acid solution of 0.3mol/L, anode alumina foil 4h under the voltage of room temperature and 30V, in the H3PO4 of 6wt% and the H2CrO4 mixed solution of 1.8wt%, in the water-bath of 60 DEG C, remove surface oxidation aluminium lamination, in the oxalic acid solution of 0.3mol/L, anode alumina foil 2h under the voltage of room temperature and 30V, corrosion oxidation aluminium foil at 30 DEG C of phosphoric acid solutions in 5%, obtains nano-alumina template;

(2) nano-alumina template is carried out to slowly dry processing, put into inert gas at 1150 DEG C, sintering time is 2h, obtains catalyst carrier;

(3) raw material of following mass parts is mixed: the CeO2 of 1.6 parts, the Y2O3 of 1 part, the ZrO2 of 0.4 part, the γ-Al2O3 of 60 parts, add RhCl3, the PtCl3 of 4 parts at 500 DEG C of roasting 2h and 110 DEG C of dry powdered form catalyst that obtain for 2 hours;

(4) powdered form catalyst is mixed by the weight ratio of 1:2 with water, add acid to make pH value between 3-4, ball milling 8h, obtains catalyst-coated liquid;

(5) in the mode of flooding by catalyst carrier hanging, coating liquid unnecessary in the catalyst carrier after hanging is removed, at 100 DEG C, dry 20min, then put into Muffle furnace in 300 DEG C of roasting temperature 20min;

(6) repeating step (5) once;

(7) catalyst carrier of step (6) is placed in to Muffle furnace in 350 DEG C of roasting 2h, and is incubated 8h.