The
mechanical strength of industrial catalysts and adsorbents is of
outstanding importance for their manufacturing and packaging, as well as
during loading and operation in the reactors. Two different mechanical
characteristics are measured to determine this mechanical strength : the
crush resistance and the attrition / abrasion resistance.
Vinci-Technologies offers two different testers to measure the
attrition and abrasion resistance of granular catalysts & adsorbents
: the Rotating Tube attrition Tester (SPENCE method) (RTT) and the
Rotating Drum attrition Tester (ASTM D-4058-96) (RDT). They differ by
the operating conditions of the test (rpm, duration of time) and the
size of the sieve used to recover the fines at the end of the test
procedure.
RTT - Rotating Tube attrition Tester (Spence Method)
This equipment is used to determine the attrition characteristics of a solid catalyst resulting from inter-particle friction or wall effect when the catalyst is handled under industrial conditions, especially in fluidized bed reactors in refining plants. Samples of catalysts (up to four), 25 grams each, are loaded into four cylindrical metal tubes of specific dimensions implemented on a disc-shaped frame.
The frame rotates at a speed of 25 rpm for one hour. At the end of this period of time the content of each tube is recovered and screened over a sieve.
The aperture of the sieve must be 2/3 of the smallest dimension of the granules (this mean an aperture of 1 mm for an extrudate of 1.5 mm diameter and 5 mm length).
The range of fines here is thus larger than in the ASTM test. Initial sample, residue on the sieve and "fines" are weighted and attrition is calculated.
Download : Attrition & Abrasion testers brochure
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