Chemical Catalyst Extruders

Hydrotreating, hydrocracking, and catalytic reforming catalysts based on alumina, silica-alumina, and zeolite supports shaped into trilobe and quadrilobe extrudates represent the largest single market for catalyst extrusion. The geometric precision required for these bodies – trilobe or quadrilobe cross-sections with tolerances of tenths of millimetres – controls bed packing density and pressure drop in fixed-bed reactors that may contain hundreds of tonnes of catalyst, making dimensional consistency a direct factor in the operational economics of the refinery unit.

Catalysts for ethylene oxide production, acrylonitrile synthesis, propylene oxidation, and polymerisation reactions commonly require promoted mixed-oxide paste formulations that contain halides, organic acids, or other corrosive promoters – conditions that directly dictate the metallurgical specification of the extruder. The CT series’ availability in 316SS and 17-4PH stainless steel makes it the preferred platform for the full range of petrochemical catalyst paste chemistries.

DeNOx SCR catalysts for stationary and mobile emissions applications, VOC oxidation catalysts for industrial air treatment, and diesel oxidation catalysts for automotive applications all require extruded bodies with geometric and structural properties that are determined at the extrusion stage. For DeNOx honeycomb catalysts in particular, wall thickness and cell pitch tolerances are direct determinants of catalyst light-off temperature and back-pressure – and therefore of the catalyst’s ability to meet emissions targets under real driving conditions.

Adsorbent and guard-bed materials for hydrogen sulfide removal, mercury capture, and desiccant applications in natural gas treating systems require extruded bodies with crush strength sufficient to survive bed loading, cyclic pressure changes, and fluidisation without generating fines that would contaminate the process gas stream. The CT extruder’s ability to produce pellets with consistent geometry and green density is directly responsible for the pellet-to-pellet crush strength uniformity that guard bed operators rely on.

Catalyst bodies for pharmaceutical intermediate synthesis, agrochemical production, and specialty oxidation chemistry are typically produced in smaller quantities with more complex formulations and more stringent quality requirements than commodity refining catalysts. The CT 1 and CT 2.25 laboratory and small-production models are particularly relevant for these applications, where batch sizes are small, formulation development is ongoing, and the ability to change die geometries and screw configurations rapidly is more important than raw throughput.