CN105370350A - 一种汽车三元催化器的封装方法 - Google Patents

一种汽车三元催化器的封装方法 Download PDF

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CN105370350A
CN105370350A CN201510710060.7A CN201510710060A CN105370350A CN 105370350 A CN105370350 A CN 105370350A CN 201510710060 A CN201510710060 A CN 201510710060A CN 105370350 A CN105370350 A CN 105370350A
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catalyst converter
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孟晓辉
孟雷军
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Suzhou Lianchi Environmental Science & Technology Development Co Ltd
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01NGAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/24Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
    • F01N3/28Construction of catalytic reactors
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/002Mixed oxides other than spinels, e.g. perovskite
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/38Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
    • B01J23/54Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/56Platinum group metals
    • B01J23/63Platinum group metals with rare earths or actinides
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01NGAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/24Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
    • F01N3/28Construction of catalytic reactors
    • F01N3/2839Arrangements for mounting catalyst support in housing, e.g. with means for compensating thermal expansion or vibration
    • F01N3/2842Arrangements for mounting catalyst support in housing, e.g. with means for compensating thermal expansion or vibration specially adapted for monolithic supports, e.g. of honeycomb type
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2523/00Constitutive chemical elements of heterogeneous catalysts
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01NGAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2370/00Selection of materials for exhaust purification
    • F01N2370/02Selection of materials for exhaust purification used in catalytic reactors
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02ATECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A50/00TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
    • Y02A50/20Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02TCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00Road transport of goods or passengers
    • Y02T10/10Internal combustion engine [ICE] based vehicles
    • Y02T10/12Improving ICE efficiencies

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Abstract

本发明涉及汽车三元催化器制备领域,具体涉及一种汽车三元催化器的封装方法,包括如下步骤:在蜂窝状载体上形成净化剂层;将具有净化剂层的载体在400-600摄氏度焙烧1-2小时后,在0-4摄氏度环境中冷却;将具有净化剂层的载体放入催化器壳体的一半,并使催化器壳体的两半式结构合拢,具有净化剂层的载体和催化器壳体内壁之间有一定距离,通过下压定位板使催化器壳体内壁和外壁压缩以使具有净化剂层的载体和催化器壳体内壁贴合。本发明采用上述的方法,方便了净化剂载体的安装与拆卸,减少净化剂载体的受压形变;采用特定组分的净化剂并分层涂布,提高了催化效果。

Description

一种汽车三元催化器的封装方法
技术领域
本发明涉及汽车三元催化器制备领域,具体涉及一种汽车三元催化器的封装方法。
背景技术
汽车三元催化器是安装在汽车排气***中最重要的机外净化装置,可将汽车尾气排出的一氧化碳、氧化氮和碳氢化合物等有害气体通过氧化和还原作用转变为无害的二氧化碳、水和氮气。由于这种催化器可同时将废气中的三种主要有害物质转换为无害物质,故称三元催化器。
汽车三元催化器在制备过程中,需要封装于催化器壳体内,但载体上首先需要涂布不同活性成分并实现净化剂层的成型,净化剂载体还需牢固封装于催化器壳体内,现有技术中往往净化剂载体牢固封装于催化器壳体后,拆卸净化剂载体较为麻烦。
发明内容
本发明针对现有技术的不足,提供了一种实现牢固封装、方便拆卸、催化效果好的汽车三元催化器的封装方法。
本发明采用以下技术方案:一种汽车三元催化器的封装方法,其特征在于,包括如下步骤:
(1)在蜂窝状载体上形成净化剂层,即形成具有净化剂层的载体;
(2)将具有净化剂层的载体在400-600摄氏度焙烧1-2小时后,在0-4摄氏度环境中冷却;
(3)制备催化器壳体,催化器壳体为两半式结构,催化器壳体的一半与进气管连接,另一半和排气管连接;催化剂壳体的内壁和外壁有弹性,催化剂壳体的外壁外侧贴合定位板,内壁与外壁贴合;将步骤(2)得到的具有净化剂层的载体放入催化器壳体的一半,并使催化器壳体的两半式结构合拢,具有净化剂层的载体和催化器壳体内壁之间有一定距离,通过下压定位板使催化器壳体内壁和外壁压缩以使具有净化剂层的载体和催化器壳体内壁贴合。
前述的一种汽车三元催化器的封装方法,在步骤(1)中,形成净化剂层的步骤具体为:将氧化铝粉末1-3份、铝溶胶0.5-1份加热至熔融并涂布于载体表面,冷却固化后形成净化剂第一层;再将二氧化铈和二氧化锆的混合物0.1-0.3份、硝酸钯1-3份、硝酸铑0.5-1份、过硫酸铵0.2-0.3份、亚硫酸氢钠0.2-0.3份、去离子水1-5份混合后涂布于净化剂第一层上,形成净化剂第二层。
前述的一种汽车三元催化器的封装方法,在步骤(3)中,催化器壳体的两半式结构合拢的方式为:通过螺栓式结构实现两半式结构连接,同时两半式结构之间由密封层密封。
前述的一种汽车三元催化器的封装方法,在步骤(3)中,通过将定位板的一端固定于排气管表面,另一端固定于进气管的表面实现定位板固定。
前述的一种汽车三元催化器的封装方法,在步骤(3)中,所述的一定距离指0.1-0.5cm。
前述的一种汽车三元催化器的封装方法,在步骤(2)中,在0-4摄氏度环境中冷却1-3小时。
本发明采用上述的方法,通过实现催化器壳体的两半式结构封装,以及催化器壳体壁的弹性结构,方便了净化剂载体的安装与拆卸,同时在净化剂载体受风压迫时,压迫力传导到弹性壳体壁,能够减少净化剂载体的受压形变;采用特定组分的净化剂并分层涂布,提高了催化效果。
具体实施方式
下面结合具体实施例对本发明作进一步详细介绍。
实施例1
一种汽车三元催化器的封装方法,包括如下步骤:
(1)在蜂窝状载体上形成净化剂层;形成净化剂层的步骤具体为:将氧化铝粉末2份、铝溶胶0.6份加热至熔融并涂布于载体表面,冷却固化后形成净化剂第一层;再将二氧化铈和二氧化锆的混合物02份、硝酸钯2份、硝酸铑1份、过硫酸铵0.2份、亚硫酸氢钠0.2份、去离子水3份混合后涂布于净化剂第一层上,形成净化剂第二层。
(2)将步骤(1)得到的具有净化剂层的载体在400-600摄氏度焙烧1-2小时后,在0-4摄氏度环境中冷却1-3小时;
(3)制备催化器壳体,催化器壳体为两半式结构,催化器壳体的一半与进气管连接,另一半和排气管连接;催化剂壳体的内壁和外壁有弹性,催化剂壳体的外壁外侧贴合定位板,内壁与外壁贴合;将步骤(2)得到的具有净化剂层的载体放入催化器壳体的一半,并使催化器壳体的两半式结构合拢,具有净化剂层的载体和催化器壳体内壁之间有一定距离(比如0.5cm),通过下压定位板使催化器壳体内壁和外壁压缩以使具有净化剂层的载体和催化器壳体内壁贴合。催化器壳体的两半式结构合拢的方式为:通过螺栓式结构实现两半式结构连接,同时两半式结构之间由密封层密封。通过将定位板的一端固定于排气管表面,另一端固定于进气管的表面实现定位板固定。
利用实施例1制备的三元催化器,检测其对尾气中CO的吸收率为92.2%,对尾气中氮氧化合物的吸收率为93.0%,对尾气中碳氢化合物的吸收率为92.6%。
实施例2
一种汽车三元催化器的封装方法,包括如下步骤:
(2)在蜂窝状载体上形成净化剂层;形成净化剂层的步骤具体为:将氧化铝粉末1.5份、铝溶胶0.8份加热至熔融并涂布于载体表面,冷却固化后形成净化剂第一层;再将二氧化铈和二氧化锆的混合物0.3份、硝酸钯3份、硝酸铑0.5份、过硫酸铵0.3份、亚硫酸氢钠0.2份、去离子水4份混合后涂布于净化剂第一层上,形成净化剂第二层。
(2)将步骤(1)得到的具有净化剂层的载体在400-600摄氏度焙烧1-2小时后,在0-4摄氏度环境中冷却1-3小时;
(3)制备催化器壳体,催化器壳体为两半式结构,催化器壳体的一半与进气管连接,另一半和排气管连接;催化剂壳体的内壁和外壁有弹性,催化剂壳体的外壁外侧贴合定位板,内壁与外壁贴合;将步骤(2)得到的具有净化剂层的载体放入催化器壳体的一半,并使催化器壳体的两半式结构合拢,具有净化剂层的载体和催化器壳体内壁之间有一定距离(比如0.4cm),通过下压定位板使催化器壳体内壁和外壁压缩以使具有净化剂层的载体和催化器壳体内壁贴合。催化器壳体的两半式结构合拢的方式为:通过螺栓式结构实现两半式结构连接,同时两半式结构之间由密封层密封。通过将定位板的一端固定于排气管表面,另一端固定于进气管的表面实现定位板固定。
利用实施例1制备的三元催化器,检测其对尾气中CO的吸收率为91.9%,对尾气中氮氧化合物的吸收率为92.5%,对尾气中碳氢化合物的吸收率为93.2%。
需要说明的是,以上所述仅为本发明的实施例,并非因此限制本发明的专利范围,凡是利用本发明说明书内容所做的等效结构或等效流程变换,或直接或间接运用在其他相关技术领域,均同理包括在本发明的专利保护范围内。

Claims (6)

1.一种汽车三元催化器的封装方法,其特征在于,包括如下步骤:
(1)在蜂窝状载体上形成净化剂层,即形成具有净化剂层的载体;
(2)将具有净化剂层的载体在400-600摄氏度焙烧1-2小时后,在0-4摄氏度环境中冷却;
(3)制备催化器壳体,催化器壳体为两半式结构,催化器壳体的一半与进气管连接,另一半和排气管连接;催化剂壳体的内壁和外壁有弹性,催化剂壳体的外壁外侧贴合定位板,内壁与外壁贴合;将步骤(2)得到的具有净化剂层的载体放入催化器壳体的一半,并使催化器壳体的两半式结构合拢,具有净化剂层的载体和催化器壳体内壁之间有一定距离,通过下压定位板使催化器壳体内壁和外壁压缩以使具有净化剂层的载体和催化器壳体内壁贴合。
2.根据权利要求1所述的一种汽车三元催化器的封装方法,其特征在于,在步骤(1)中,形成净化剂层的步骤具体为:将氧化铝粉末1-3份、铝溶胶0.5-1份加热至熔融并涂布于载体表面,冷却固化后形成净化剂第一层;再将二氧化铈和二氧化锆的混合物0.1-0.3份、硝酸钯1-3份、硝酸铑0.5-1份、过硫酸铵0.2-0.3份、亚硫酸氢钠0.2-0.3份、去离子水1-5份混合后涂布于净化剂第一层上,形成净化剂第二层。
3.根据权利要求1所述的一种汽车三元催化器的封装方法,其特征在于,在步骤(3)中,催化器壳体的两半式结构合拢的方式为:通过螺栓式结构实现两半式结构连接,同时两半式结构之间由密封层密封。
4.根据权利要求1所述的一种汽车三元催化器的封装方法,其特征在于,在步骤(3)中,通过将定位板的一端固定于排气管表面,另一端固定于进气管的表面实现定位板固定。
5.根据权利要求1所述的一种汽车三元催化器的封装方法,其特征在于,在步骤(3)中,所述的一定距离指0.1-0.5cm。
6.根据权利要求1所述的一种汽车三元催化器的封装方法,其特征在于,在步骤(2)中,在0-4摄氏度环境中冷却1-3小时。
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