Purpose and characteristics
Propylene, as one of the main raw materials of organic synthesis industry, is widely used in the synthesis of organic products. Because most of the catalysts for subsequent synthesis are usually composed of precious metals, or the amount is very small (generally ppm level), they are particularly sensitive to sulfur and chlorine. A little sulfur and chlorine in the raw materials can lead to poisoning and deactivation.
Hdl-1 catalyst is a COS hydrolysis catalyst which can be used at normal and low temperature with active alumina as support and several special active components added. The activity stability of the catalyst is obviously better than that of the conventional active alumina alkaline hydrolysis agent. The operation in series with Desulfurizer at room temperature can remove the micro amount of H2S, cos, CS2 and other sulfides in liquid-phase propylene, and protect the normal operation of post sequence synthesis catalyst. The reaction is as follows:
COS+H2O---- → H2S+CO2 ----------------- (1)
CS2+2H2O-----→ 2H2S+CO2----------------- (2)
H2S+ZnO--- -→ ZnS+H2O ----------------- (3)
Form | A12O3 |
Appearance | White globule |
Specifications | Φ3-5mm |
Anti-crush strength | ≥50N/ |
Bulk density | 0.7-0.8kg/L |
COSConversion rate |
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The catalyst has high activity. It reacts at room temperature or low temperature. Due to the large chemical adsorption potential of the surface, a large number of sulfides in propylene, such as H2S, CS2, CH3SH, cos, can interact with the electron acceptor center on the surface of active alumina to form surface compounds, such as sulfonates, sulfates, thiosulfates and thiocarboxylates.
The catalyst can not only hydrolyze organic sulfides, adsorb various sulfides and form stable compounds with their surfaces, but also remove chlorides such as HCI and cyanide. The 500 hour activity test showed that hdl-1 catalyst can remove more than 90% of the chlorine in liquid phase propylene, and the chlorine capacity of the top catalyst was 0.6% (weight).
temperature | 10-180℃(Operation above dew point) |
pressure | Atmospheric pressure-8.0Mpa |
Liquid space velocity | 1-5hr-1 |
Sulphur content(以COS、H2S为主) | 1-10ppm |
H2Ocontent | 100ppmAbout |
Bed height / tower diameter | >3 |
After treated with hdl-1 catalyst and Desulfurizer at room temperature, the content of s in liquid propylene is less than 0.1ppm, and the service life of catalyst is more than 1.0 years.
Driving and parking
1. When starting up hdl-1 catalyst unit, all outlet valves shall be closed first, and then the inlet valve of liquid-phase crude propylene shall be opened to boost the pressure at the rate of 0.5MPa every 10 minutes.
2. When the pressure is balanced with the feed pressure, the outlet valve of the device can be opened slowly and operated at 1 / 4 full load for 4 hours. During this period, the sulfur content at the analysis outlet shall not be greater than 0.1ppm.
3. After the H2S content at the outlet of the unit is qualified, gradually increase the load to 1 / 2 of the full load, and then transfer to the full load operation after stabilizing for 3-5 hours.
4. Avoid large fluctuation of pressure and load as much as possible in the process of use, so as not to affect the service life of catalyst
5. During shutdown, the feed valve shall be closed first, and the outlet valve shall be closed after the pressure of the device drops, so as to isolate the device from the system.
6. The adsorption rate of hdl-1 catalyst is very good under pressure, but partial desorption will occur during pressure reduction. Therefore, when stopping and pressure relief, attention shall be paid to prevent the sulfide desorbed from being introduced into the post system (the unit shall be equipped with recovery and vent pipelines).
Packaging, storage and transportation
The iron bucket or cardboard bucket is lined with two layers of plastic bags, with a net weight of 50kg per barrel. Hdl-1 catalyst shall be sealed, waterproof and moisture-proof, and it is not allowed to contact with other chemicals. During transportation, it is necessary to avoid falling, rolling and impact of packaging barrel. Sealed storage for 3-5 years does not affect its activity, it can be used as usual.