Hydrochlorination of acetylene using supported phosphorus-doped Cu-based catalysts

Abstract

Phosphorus-doped copper catalysts supported on spherical activated carbon (SAC) were prepared using an incipient wetness impregnation technique. The catalysts were characterized by low-temperature N 2 adsorption/desorption, X-ray diffraction (XRD), transmission electron microscopy (TEM), temperature programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma (ICP), N 2 O pulse titration method and thermogravimetric (TG) technologies. The results indicate that the phosphorus-doped Cu-based catalysts exhibit both high activity and good stability. The amount of phosphorus dopant has a significant effect on the catalytic activity of acetylene hydrochlorination and the optimal molar ratio of Cu/P is 2.5. The phosphorus doping facilitates the dispersion of copper species, enhances the interaction between metal and support, and restrains the growth of copper species during acetylene hydrochlorination. These results suggest that this high-activity, good-stability and low-cost catalyst has a great potential in industrial applications. 3 becoming urgent. It is known that Cu-based catalysts have been intensively investigated due to its higher activity for vapor-phase hydrogenation reaction. 16 Similarly, Cu-based catalysts as an alternative can also have good activity in acetylene hydrochlorination. Zhou, 17 for example, studied the copper chlorides NPs loaded on the nitrogen-doped carbon nanotubes (N-CNTs) for acetylene hydrochlorination and concluded that the Cu-NCNT catalyst (2.4% N) offers promoted reactivity for sustainable hydrochlorination. But, it still remains unclear what role the copper species play in the acetylene hydrochlorination reaction and in the deactivation mechanism of Cu-based catalysts, thus it is needed to be further studied.As we all know, dopants of non-metal elements like nitrogen, boron and phosphorus on carbon material can improve the performance of the catalysts for the oxygen reduction reaction. 18-21 Peng and co-workers 22, 23 prepared P-doped graphitic layers and carbon nanotubes to show high ORR performance and they found that phosphorus dopant can change the electronical structure in the network of graphitic layers so as to improve the electrocatalytic activity of catalysts. Cheng 24 found that the ORR activity can be improved owing to the formation of more structural defects after inducing phosphorus. Yang 25 reported that phosphorus doping on the standard Fe-N/C ORR catalyst exhibited a much enhanced ORR performance and the phosphorus doping process might not alter the nature of active sites but lead to the increase of ORR active site density and better dispersion of them on the catalyst surface. However, whether the P-dopant can improve the activity and the stability of 5 of Cu/P. The carbon-supported cupric pyrophosphate catalyst was also prepared using an incipient wetness impregnation technique. The pretreated carbon (5.0 g) was added to a solution of Cu 2 P 2 O 7 (A.R.) (5 mL) and maintained at 80 ºC for 12 h. The catalysts were dried at 120 °C ...

The Effect of N‐Doping in Activated Carbon‐Supported Au‐Sr Catalysts for Acetylene Hydrochlorination to Vinyl Chloride

“…In previous studies of numerous metal chlorides and carbon catalytic materials,, activated carbon‐supported AuCl 3 catalyst (AuCl 3 /AC) as a green and efficient non‐mercury catalyst is considered to be most promising alternative to HgCl 2 /AC catalyst for acetylene hydrochlorination ,. Compared with HgCl 2 /AC catalyst, AuCl 3 /AC catalyst exhibits better initial activity.…”

Synthesis and Characterization of X–MOF/AC (X=tin or copper) Catalysts for the Acetylene Hydrochlorination

“…As can be seen in Figure a, the acetylene conversion over 10%Sn‐MOF/AC decreased from 93.5% to 52.6% after 40 h. However, the 10%SnCl 2 /AC catalyst was quickly inactivated after 10 h. Although non‐precious metals exhibit lower toxicity and better catalytic properties, metal chloride catalysts exhibit a lower stability . Compared to 10%SnCl 2 /AC and 17%ZIF‐8/SAC, after interacting with o‐phthalic acid, 10%Sn‐MOF/AC revealed a relatively higher stability and activity for the hydrochlorination of acetylene.…”

“…For instance, Zhang et al . reported that carbon‐supported Cu−P/AC can catalyze the acetylene hydrochlorination with 97.2% acetylene conversion; at same time, the introduction of phosphorus in Cu(II)‐based catalysts can effectively promote the lifetime compare to CuCl 2 /AC . Dai et al .…”

An Alternative Carbon Carrier in Green Preparation of Efficient Gold/Carbon Catalyst for Acetylene Hydrochlorination

“…The energy structure of China's rich coal and lean oil dictates that the production of vinyl chloride monomer (VCM) by acetylene hydrochlorination is the best route for large-scale production of polyvinyl chloride (PVC). [1] Considerable research efforts have been devoted to developing mercury-free catalysts, such as AC-supported AuCl 3 , [2][3][4] PdCl 2 , [5][6][7] RuCl 3 , [8,9] and CuCl 2 [10,11] to replace conventional Hg-based catalysts in the hydrochlorination of acetylene because of the mercuric chloride lost from the catalyst can disperse into the environment, which will seriously endanger human health. Hutchings and coworkers showed that Au catalysts are the most promising mercury-free catalysts.…”