Swiss specialty chemicals producer Clariant has won a contract from China’s Hengli Petrochemical (Dalian) Refinery to develop a propane and butane dehydrogenation unit in cooperation with engineering contractor CB&I. The single-train unit, which Clariant said would be the world’s largest when completed, will be built in Dalian in the province of Liaoning. It will be capable of processing 300,000 t/y of propane and 600,000 t/y of isobutane into propylene and isobutylene respectively.

The design will be based on CB&I’s Catofin catalytic dehydrogenation technology using Clariant’s tailor-made catalyst and Heat Generating Material (HGM). A metal-oxide material, HGM is designed to significantly increase the selectivity and yield of Catofin units. It is loaded with the catalyst into the catalyst bed where it oxidates and reduces during operation, producing heat and driving the dehydrogenation reaction. As well as boosting yields, HGM is said to save energy and reduce emissions.

Clariant said Hengli’s plant will be the second co-processing unit to use HGM, following the success of one designed for Shandong Sincier Petrochemical in Dongying, Shandong province. The company added that HGM had also performed very well at Ningbo Haiyue New Material’s propane dehydrogenation plant in Ningbo City, China.

Daniel McCarthy, president of CB&I’s Technology operating group said Catofin technology offered proven reliability and the flexibility to co-process multiple feed compositions at world-scale capacities.

The Catofin process operates at optimum reactor pressure and temperature to maximize propane and isobutane conversion at high yields with correspondingly low investment and operating costs.