CN102909089A - Catalyst granule for dimethyl ether - Google Patents

Abstract

The invention discloses a solid catalyst granule used in the process of preparing dimethyl ether through a heterogeneous catalytic reaction, in particular to a catalyst granule used in the process of directly preparing the dimethyl ether by a one-step method in a slurry bed reactor. An outer contour line of a radial cross section of the catalyst granule is in a continuous and smooth six-tooth gear shape, and a through hole is formed along a central axis. The catalyst granule is large in specific surface area and high in abrasive resistance.

Description

A kind of dimethyl ether catalyst particle

Technical field

The present invention relates to the solid catalyst particle that uses in a kind of heterogeneous catalytic reaction preparation of dimethyl ether process, relate in particular to a kind of catalyst granules that in paste state bed reactor, uses in the one-step method direct preparation of dimethyl ether technique.

Background technology

In the one-step method synthesis process for dimethyl ether, what reactor adopted is paste state bed reactor.Catalyst exists with graininess in the slurries of high gas holdup, and synthesis gas enters into bed and forms tiny homogeneous from the bottom bubble is upward through catalyst bed reaction.So; this technique belongs to gas-liquid-solid reaction; the shape of catalyst and intensity have significant impact to reaction; high specific area can provide the space of more gas-liquid contacts; and high mechanical strength especially scuff resistance for guaranteeing the stable also extremely important of catalytic reaction, because can constantly bump friction in the paste state bed reactor between the catalyst granules, if insufficient strength; particle can break, and too much breaking must affect the catalytic reaction effect.Therefore, to the requirement of catalyst, both need high specific area in this technique, needed again high mechanical strength.

Summary of the invention

The technical problem that mainly solves among the present invention is to reduce local stress to concentrate when improving the catalyst granules specific area, thereby can improve the scuff resistance of catalyst granules.According to mechanics principle, reduce the concentrated method of stress is to make the monnolithic case of member realize rounding off as far as possible.For this reason, the outer contour of the radial cross-section of catalyst granules main body is continuous, the smooth gear shape that is joined end to end and formed by the tangent minor arc of multistage among the present invention.Because like this characteristic function of the curve of shape has the continuous derivative of single order, thus according in the higher mathematics to the judging rules of smooth curve, the outer contour of catalyst granules cross section is smooth curve among the present invention.Having the frictional force of the in theory minimum except circle and minimum stress on the outer contour of this feature concentrates; And with respect to common cylinder, this gear-like of catalyst granules has higher specific area among the present invention.In sum, the present invention has also significantly reduced local stress when improving the catalyst granules specific area, has reached the effect that improves the catalyst granules scuff resistance.

Concrete technical scheme of the present invention comprises:

A kind of solid catalyst particle of six gear shapes, the main body axial component is highly to be H, have clear opening along axis, the aperture of clear opening is D, the radial cross-section outer contour of catalyst granules is continuous, smooth six gear shapes, and the circumradius of outer contour is R, and inscribed circle radius is r.

Form above-mentioned catalyst granules main body radial cross-section continuous smooth gear-like outer contour be the curved section (as shown in Figure 1) with following feature: one group of quantity is 6, radius is the circle of β, around central point O, circular array in 0 ° to 360 ° scope; Do following three circles, be that (center of circle among Fig. 1 is O for the inscribed circle of outer contour, radius is the circle of r), and the circumcircle (such as the round S among Fig. 1) of 2 adjacent radiuses circle (such as the round P among Fig. 1 and circle Q) that is β, obtain another and organize quantity and be all 6 circle; Respectively from this circle of two groups, mutually circumscribed (mutually circumscribed with circle S such as circle P among Fig. 1 between any two, circle S is mutually circumscribed with circle Q), each circle is upper to form corresponding 2 point of contacts (such as the some A on the circle P among Fig. 1 and some B, some B on the circle S and some C), get the minor arc between these two point of contacts, these all minor arcs join end to end and consist of this continuously outer contour of smooth gear-like of cross section.

The various relevant parameters of above-mentioned formation catalyst particles grain character are of a size of:

R?=1mm?~3mm；

r?=?0.8R；

H?=?2R?~?2.2R；

β?=?0.2R；

D?=?0.3R。

Outline of the present invention is smooth continuously, and local stress is little, when improving the catalyst granules specific area, has more significantly improved the scuff resistance of catalyst granules.

Description of drawings

Fig. 1 is that catalyst granules cross section outer contour of the present invention forms schematic diagram.

Fig. 2 is the embodiment of the invention 1 cross sectional representation (also being the cross sectional representation of embodiment 2 and embodiment 3 simultaneously).

The specific embodiment

Below in conjunction with drawings and Examples the present invention is further detailed:

The marked improvement of technical solution of the present invention has been to improve the scuff resistance of catalyst granules, and scuff resistance can be investigated by this index of wear rate.Adopt the small-sized seed-coating machine of BY-300A type that Shanghai Huanghai Sea medicine inspection Instr Ltd. produces (stainless steel coating pan diameter 200 mm processed, the coating pan inclination angle is 35 to spend) during the wear rate of specimen particle.During test, every kind of sample is randomly drawed 200, puts into coating pan, the coating pan rotating speed is controlled to be 60 rev/mins, keeps rotating speed to stop after 1 hour, takes out particle, the particle number W that the reading contour structures is complete, meter abrasion of particles rate ω=[(200-W)/200] * 100%.

Related catalyst granules of the present invention all is according to these particles architectural feature separately in the specific embodiment, adopts same material and facility to prepare.

The following examples only are used for the present invention that explains in detail, and limit the scope of the invention never in any form.

Embodiment 1

The cross sectional representation of catalyst granules such as Fig. 2 in the present embodiment, the design parameter size sees Table 1.Catalyst granules body height H=4.4 mm; Clear opening diameter D=0.6 mm; The circumradius R of catalyst granules radial cross-section outer contour=2 mm, inscribed circle radius r=1.6 mm, radius β=0.4 mm.This catalyst granules wear rate ω is 8.5%.

Embodiment 2

The cross sectional representation of catalyst granules such as Fig. 2 in the present embodiment, the design parameter size sees Table 1.Catalyst granules body height H=6.3 mm; Clear opening diameter D=0.9 mm; The circumradius R of catalyst granules radial cross-section outer contour=3 mm, inscribed circle radius r=2.4 mm, radius β=0.6 mm.This catalyst granules wear rate ω is 7%.

Embodiment 3

The cross sectional representation of catalyst granules such as Fig. 2 in the present embodiment, the design parameter size sees Table 1.Catalyst granules body height H=2 mm; Clear opening diameter D=0.3 mm; The circumradius R of catalyst granules radial cross-section outer contour=1 mm, inscribed circle radius r=0.8 mm, radius β=0.2 mm.This catalyst granules wear rate ω is 8%.

Table 1

?	H (mm)	D (mm)	R (mm)	r (mm)	β (mm)	ω %
							Embodiment 1	4.4	0.6	2	1.6	0.4	8.5
Embodiment 2	6.3	0.9	3	2.4	0.6	7
							Embodiment 3	2	0.3	1	0.8	0.2	8

Claims (7)

1. one kind is used for the solid catalyst particle that heterogeneous catalytic reaction preparation of dimethyl ether process is used, the radial cross-section outer contour that it is characterized in that catalyst granules is continuous, smooth six gear shapes, and the circumradius of outer contour is (R), and inscribed circle radius is (r); The catalyst granules axial height is (H), has diameter along axis and is the clear opening of (D).

2. catalyst granules as claimed in claim 1, this continuously smooth gear-like outer contour that it is characterized in that the main body radial cross-section is comprised of the curved section with following feature: one group of quantity is 6, radius is the circle of (β), around central point (O), in 0 degree circular array in the 360 degree scopes; Do the inscribed circle of outer contour and adjacent 2 radiuses and be the circle of (β), it is 6 circle that the circumcircle of these three circles, these circumcircles form another group quantity; From these two groups circles, between any two mutually circumscribed respectively, the minor arc between these two point of contacts is got at corresponding 2 point of contacts of the upper formation of each circle, and these all minor arcs join end to end and consist of this continuously outer contour of smooth gear-like of cross section.

3. catalyst granules as claimed in claim 1 is characterized in that outer contour circumradius (R) is 1 mm to 3 mm.

4. catalyst granules as claimed in claim 1 is characterized in that outer contour inscribed circle radius (r) is 0.8R.

5. catalyst granules as claimed in claim 2 is characterized in that radius (β) is 0.2R.

6. catalyst granules as claimed in claim 1 is characterized in that along the clear opening diameter (D) that axis is opened be 0.3R.

7. catalyst granules as claimed in claim 1, the axial height (H) that it is characterized in that particle is 2R to 2.2R.