We are the sole developer and manufacturer in the world for the pre-sulfided sulfur-resistant CO-shift catalysts by ex-situ presulfiding and passivating technology (KTRES), the newly invented catalysts have been installed and successfully operated in almost 30 large-scale coal-based chemical facilities.

 

The novel technology of ex-situ deep presulfiding and accompanying passivating processes for sulfur-resistant shift catalysts were developed by Professor Xintang ZHANG, over a decade’s R&D work. The ex-situ presulfiding technology features shift catalysts with higher sulfur uptake and higher operating stability. The pre-sulfided sulfur-resistant shift catalysts eliminate the catalyst sulfidation stage, which debottlenecks the troublesome start-up process for using the conventional shift catalysts. All shift catalysts can be supplied in pre-sulfided state, allowing an economical efficient and simplified operation by avoiding the use of flammable and toxic agents during start-up. The outstanding advantages of the ex-situ pre-sulfided sulfur-resistant shift catalyst technology have been summarized as below:

1) Same as for the conventional sulfur-resistant shift catalyst, no special protection is required during packing and transportation as the passivated pre-sulfided catalysts do NOT get oxidized in the presence of air, while other kinds of sulfided catalysts require special protections to prevent from contacting with air.

 

2) The ex-situ deep sulfidation provides the higher catalytic activity, higher operating stability and longer working life compared to the conventional sulfur-resistant shift catalysts.

 

3) Significantly reduces the process startup time (by 2/3) and costs as the production can be started immediately after the catalyst is pre-heated to the required inlet temperature under N₂ flow.

 

4) Since no sulfidation stage is required for start-up of the new pre-sulfided catalyst, the usage of H₂, CS₂ and other sulfiding reagents are eliminated, therefore, the new process reduces pollutions and greatly enhances process safety.

 

5) Neither the catalysts and or the passivator contains any undesired components, such as potassium and sodium ions that may cause equipment corrosions. The passivator can be decomposed to water, N₂ and CO₂ which can be vented along with the N₂ purge gas during temperature ramp at the process startup stage.

 

6) Compared to the conventional sulfur-resistant shift catalyst, the new pre-sulfided catalyst features 15 % higher catalytic activity, with a greater mechanical strength and better catalytic stability. The detailed experimental data for both conventional and pre-sulfided catalysts has approved this conclusion. 

 

7) The new pre-sulfided catalyst can be operated under a wider range of water/gas ratio e.g. the pre-sulfided catalyst is able to perform under the conditions of  only 15︒C above the dew point of the inlet gas, providing a high CO conversion rate.

 

8) The new pre-sulfided catalyst can be operated under the low sulfur-content conditions e.g. 0.01% sulfur, with the ability to convert organic sulfur and HCN, in which carbonyl sulfide conversion can reach as high as 95%. Additionally, the catalyst is able to remove arsenic with the anti-fouling performance.

 

9) With the 35% higher mechanical strength and improved strength stability than the conventional shift catalyst, the strength loss of the new pre-sulfided catalysts during industrial operation is incredibly small. It is well known that catalyst strength loss and volume shrinkage may cause increased pressure drop through the reactor, which would lead to higher energy consumptions. Experiments showed the mechanical strength and catalytic activity of the catalyst made by KTRES technology are not affected after being chilled by cold water for 20 times.

 

10) With an extensive range of portfolios, the pre-sulfided sulfur-resistant shift catalysts have been successfully installed and operated in almost 30 large-capacity coal based chemical industrial facilities, in which the longest operating catalyst has been online for almost 4 years and is still performing well. In addition to the high performance catalyst, we provide technical supports to help our customers from process startup through the whole catalyst operating life cycle to ensure optimum performance of the catalysts.