Catalyst particle shape

A catalytic system comprising:

• a. a tubular reactor having a cylindrical form around an axis A-A;
• the internal surface of said tubular reactor having an internal diameter D and an internal radius of curvature R, defined in a plane perpendicular to the axis A-A;
• b. at least one catalyst particle located in said tubular reactor,
• wherein the catalyst particle has a three-dimensional shape comprising a body portion;
• said body portion being in the form of an elliptic cylinder and comprising a sidewall extending parallel to a primary axis L between a first end-face and a second end-face;
• wherein the first end-face and the second end-face are arranged perpendicular to said primary axis L at least in the region in which they cross said primary axis L;
• and
• wherein the ellipse of said elliptic cylinder has a major axis 2a and a minor axis 2b, and a radius of curvature R5 defined as:
• R
• ⁢
• 5
• =
• a
• 2
• b
• being 0.9-1.10 times the internal radius of curvature R of the tubular reactor,
• and wherein the maximum width D1 of the catalyst particle, measured in a plane perpendicular to said primary axis L, is less than 0.25 times the internal diameter D1 of the tubular reactor.

A catalyst particle having a three-dimensional form with a primary length axis L, wherein each catalyst particle has;

• a first end-face and a second end-face, arranged substantially perpendicular to said primary axis L,
• opposing first and second sidewalls extending between the first and second end-faces, each sidewall having a curved profile in a plane defined perpendicular to the primary axis L, wherein each of said first and second sidewalls independently has an external radius of curvature R2 in said plane,
• opposing third and fourth sidewalls extending between the first and second sidewalls and said first and second end-faces, each third and fourth sidewall having a curved profile in said plane defined perpendicular to the primary axis L;
• wherein each of said third and fourth sidewalls independently has an external radius of curvature R3;
• R4 in said plane, or
• wherein each third and fourth sidewall having an elliptical profile in said plane defined perpendicular to the primary axis L,
• wherein the radius of curvature R1, R2 of the first and second sidewalls is greater than the radius of curvature R3, R4 of the third and fourth sidewalls.