(676a) Green Application of Hydrogenation Catalyst Yn-1 on C4 Cut

Green Application of Hydrogenation Catalyst YN-1 on C₄ cut

zhou Du

 Yanshan Branch
of Beijing Research Institute of Chemical Industry£¬Sinopec, Beijing, China£¬102500

Abstract:

YN-1 Ni-based hydrogenation
catalyst adopts TiO₂-Al₂O₃ as its carrier in
the shape of trilobe in cross section. It is well
known that a significant synergistic interaction exists between Ni and titanium
oxide, which makes the catalyst be endowed with comparatively high activity.
More importantly, the catalyst can be operated at the lowest tolerable
temperature due to the synergistic effect; thereby the catalyst acquires higher
selectivity and minimum side reaction. Ni, as the active species, possesses
superior resistance to sulfur, especially to mercaptan.
The larger pores in the catalyst significantly favor diminishing the resistance
in the mass transfer process during the hydrogenation reaction. Its physical
property is illustrated in Table 1.

Table 1    Physical property of YN-1
hydrogenation catalyst

The YN-1 Ni-based
catalyst is suitable for selective hydrogenation of diverse distillation cuts
(C₄ ¨C C₁₀) of pyrolysis gasoline containing high content
of impurities such as sulfur, arsenic and nitrogen. In this paper, its green
application in hydrotreating C₄ cut will be discussed.

YN-1
catalyst has been successfully commercialized in 40Kton/a Butadiene Tail gas Hydrogenation
unit in Maoming division of Sinopec, China in July,
2015. This is the first industrial application which turns the C₄ tail
gas from Butadiene Extraction unit into ethylene cracking feedstock in China. The
tail gas full of C₄ olefins£¨like butadiene£© and alkynes(like
ethyl acetylene and vinyl acetylene) once was sent to torch to be lighted as
waste gas. With the development of our new C₄ hydrotreating technology,
it¡¯s now mixed with toluene and sent into hydrogenation reactor to undergo hydrogenation
reaction. After that, the olefins in it are fully saturated and are then introduced
to ethylene cracking unit after toluene separation. The schematic of C₄
cut hydrogenation technology is shown in Figure1. The hydrogenation product
which is rich in butane produces 13 wt% more ethylene than ordinary cracking
feed like naphtha, which in turn promote the ethylene production and protect
environment.

Figure1
 The schematic of C₄
cut hydrogenation technology

After
successful start up under room temperature in the plant, the hydrogenation product¡¯s
olefin content (including alkynes) is controlled bellow 0.3wt%, while that of
feed is about 40wt%, indicating that YN-1 catalyst exerts excellent activity
under low temperature on C₄ cut saturation.

Key words:

  green application;
hydrogenation; tail gas; ethylene production ; C₄ cut