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A BaF(p-BDC)0.5 catalyst was prepared by solid state reaction at room temperature with Ba(OH)2 as precursor, NH4F as F source, and H2(p-BDC) as organic ligand. The calcined samples were used as catalysts for dehydrochlorination of 1-chloro-1,1-difluoroethane to generate vinylidene fluoride (VDF) at 350 °C. Commercial production of VDF is carried out at 600–700 °C. Clearly, pyrolysis of the BaF(p-BDC)0.5 catalyst provided a promising way to prepare VDF at low temperatures. Prior to calcination, the activity of the BaF(p-BDC)0.5 catalyst was low. Following calcination at high temperatures, BaF(p-BDC)0.5 decomposed to BaF2 and BaCO3, and then the catalyst was chlorinated and fluorinated to BaClF, which showed high activity and stable VDF selectivity for dehydrochlorination of 1-Chloro-1,1-Difluoroethane to VDF.

Hydrochlorofluorocarbon (HCFC) has been widely applied as the third-generation refrigerant globally, however, the global warming potential of such gases is often 100 and 1000 times higher than that of CO 2 . Dehydrochlorination reaction offers an encouraging strategy to transform the high-global-warming-potential gases of hydrochlorofluorocarbons (HCFCs) to low-global-warming-potential gases of hydrofluoroolefins (HFOs). However, the handling of a large amount of byproduct HCl remains one of the major challenges blocking the industrialization of dehydrochlorination of HCFC-142a for the production of vinylidene fluoride (VDF). A one-pot cascade reaction combining dehydrochlorination of HCFC-142b and hydrochlorination of acetylene was first proposed to spontaneously produce valuable monomers of VDF and vinyl chloride monomer (VCM) while eliminating the tedious HCl treatment step. Both thermodynamic calculations and experimental results validate the feasibility of the cascade reaction. Five different heterogeneous catalysts were screened for the proposed cascade reaction, including monocomponent catalyst BaF 2 , NAC, bifunctional BaF 2 /NAC catalyst, and bicomponent BaF 2 -NAC-S and BaF 2 -NAC-M catalysts. Among them, the mixed BaF 2 -NAC-M catalyst demonstrated the best catalytic performance, with BaF 2 mainly acting as the dehydrochlorination site and NAC mainly acting as the hydrochlorination site. The corresponding reaction mechanism was also proposed.