CN2368741Y

CN2368741Y - Thermal resistant three-component catalyst device

Info

Publication number: CN2368741Y
Application number: CN 99210674
Authority: CN
Inventors: 张文
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-05-11
Filing date: 1999-05-11
Publication date: 2000-03-15
Anticipated expiration: 2009-05-11

Abstract

The utility model relates to a three-component catalyzing device with high temperature resistance and pollution resistance. The utility model comprises a nickel-chromium alloy combustion net, a fixed copper hoop for the combustion net, and a honeycomb-shaped three-component catalyzing net with multiple layers, wherein, the diameter of alloy wires is decreased orderly from an air inlet end A to an air outlet end B by layers. The alloy net is added with noble metal catalyzing materials such as platinum catalyzing materials, palladium catalyzing materials, rhodium catalyzing materials, etc. inside, and thus, a three-component catalyzing device with high temperature resistance and pollution resistance is formed.

Description

High temperature resistant ternary catalyzing unit

The utility model relates to a kind of ternary catalyzing unit, specifically, relates to a kind of high temperature resistant ternary catalyzing unit that is used on the automobile engine exhaust system.

A kind of known secondary combustion filtering net that is used for purifying vehicle exhaust, certain part Korean Patent for example, it comprises several layers nickel steel silk screen, fixed with copper sheet, and this is installed on the deflation hole of driving engine, the high temperature that utilizes engine chamber to discharge carries out secondary combustion to waste gas, thereby reduces emission of harmful substances.Because this technology is only paid attention to the secondary combustion to waste gas, and the used nickeliferous stainless steel wire front and rear part of its burning filtering net is a kind of diameter of mono-, so only can play cleaning of off-gas effect preferably in a certain high-temperature area under the driving engine high idle speed, and under other most of low idling speed operating modes, its clean-up effect is not satisfactory, and also can occur emission of harmful substances sometimes on the contrary increases.

In addition, as a kind of ternary catalyzing unit of well-known automobile exhaust purifier, be the passage that in its shell, is designed to have tiny cellular dividing plate, scribble adhering coating on the surface of these passages, this coating adds γ-Al by catalyst ₂O ₃Make, its thickness is generally 10 μ m～15 μ m, and contains precious metal catalyst materials such as 0.1～0.15% platinum, palladium, rhodium.And existing three-way catalytic apparatus is installed in the rear end of freeing pipe, before the noise silencer without exception.When mixing A/F control 14.7 the time, it can reach 90% to the conversion ratio of auto emission objectionable impurities.From its effect that transforms waste gas, this is a kind of more satisfactory clean-up device.Yet, because some characteristics of this three-way catalytic apparatus itself and the position of being installed, often make it aspect contamination resistance, have certain limitation, for example, when pollutants is deposited on coating surface, then can reduce its original catalytic capability, especially after having misapplied lead-bearing gasoline, just must cause occurring the fatal infringement of converter.Have, when it is in hot conditions about 1000 ℃,, firing order entanglement slow excessively such as point of ignition and cutoff etc. are former thereby when excessive discharge temperature occurring, then may destroy the coating in this ternary catalyzing unit again.

Task of the present utility model is, creates a kind of high temperature resistant, resistant to pollution ternary catalyzing unit that is directly installed on the engine exhaust hole.

The method that solves the utility model task is, adopts the Q alloy material, and as 1Cr (18～25) Ni9Ti or 00Cr (18～80) Ni9Ti, used diameter of alloy wire is 0.05～0.5mm, it is made the bed filtration net, as shown in Figure 1.Free air capacity according to various vehicles, select the nickel filament of different-diameter for use, and successively reduce diameter of alloy wire, under the various exhaust gas temperature conditions that guarantee when burning, to discharge from inlet end A to outlet side B, sufficient secondary combustion be can carry out, CO, HC and NO made _xBe able to secondary combustion or catalytic cracking.

On this basis, with the silk screen of outlet side B, adopt the Q alloy that contains catalysis materials such as platinum, palladium, rhodium.And, also this can be made into cellular multi-layer silk screen structure, as shown in Figure 2.So, when the objectionable impurities of driving engine discharge is passed this multi-layer silk screen hole, utilize the high temperature of waste gas self that CO, HC and NOx etc. are carried out catalytic reaction, make the waste gas of discharge be converted into harmless CO ₂, N ₂And H ₂O.That is to say that outlet side B mainly plays catalytic action, the refractory honeycomb shape multi-layer silk screen structure here is in order to strengthen the catalytic cracking to CO, HC and NOx.

The utility model has the advantages that, at first solved the incomplete combustion that under various vehicle conditions, causes because of driving engine effectively and caused the CO that occurs, the problem that the HC quantity discharged increases, promptly reduced the quantity discharged of CO and HC in the mode of secondary combustion in the mode of the Q alloy filament diameter that successively decreases.Secondly, in the ordinary course of things, fuel oil economic combustion at high temperature can cause occurring the increase of NOx.For this reason, utilize the used usually main catalysis material platinum of other ternary catalyzing units, palladium, rhodium etc., carry out the reaction of actv. high-temperature catalytic and decomposing N Ox etc., and reduce other various emission of harmful substances simultaneously.So it has just possessed the function of the catalytic cracking that is similar to other ternary catalyzing unit.At this, because of adopting the high temperature alloy material, and the strong impact force of discharging when relying on engine combustion, the fatal infringement of converter that reduces catalytic capability or cause thus so then there is not the pollutants deposition in this ternary catalyzing unit, and high temperature occurs and cause phenomenons such as breakdown of coating because of accidental.

The utility model is by preferred embodiment brief description in addition in conjunction with the accompanying drawings, wherein:

Fig. 1, expression the utility model adopts the Q alloy material of different-diameter, is formed under the various exhaust temperatures, all can carry out the clean-up device of secondary combustion or catalysis to automotive exharst gas.

Fig. 2, expression the utility model adopts and contains noble metal Q alloys such as platinum, palladium, rhodium, and the filtering net outlet side is made into cellular multi-layer silk screen structure.

Claims

1, a kind of high temperature resistant ternary catalyzing unit contains a Q alloy net (1) and its fixed copper hoop (2), it is characterized in that this silk screen has adopted the Q alloy material, and its alloy filament diameter is successively successively decreased from inlet end A to outlet side B.

2, high temperature resistant ternary catalyzing unit according to claim 1, it is 0.05～0.25mm and the Multilayer Nickel Chromium silk that contains noble metals such as platinum, palladium, rhodium that diameter is adopted in wherein said outlet side, and constitutes cellular three-element catalytic net with this.