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It is a special form of Nickel which comprise of finely divided
spongy Nickel particles prepared by leaching out Aluminium under
controlled conditions from a Nickel – Aluminium Alloy through
wet chemical method. The product is always kept submerged under
water or suitable solvent and accordingly, Raney Nickel is
marketed and delivered in that form, i. e slurry form. The
slurry particles are likely to catch fire, i.e turn pyrophoric
if separated from water or solvent and allowed to dry in
atmosphere.
This special form of spongy, finely divided Nickel is a very
powerful hydrogenation catalyst. This form of Nickel was first
produced by an American engineer – Murray Raney in 1927.
Unlike most other hydrogenation catalysts it is not instantly
poisoned by sulphur radicals, if present in the reactants.
Raney Nickel is a
versatile hydrogenation catalyst and is used in hydrogenation of
large number of functional groups. Notable among them being
Carbon – Carbon double bond, aldehydic, ketonic, nitro, azide,
oxime, nitrile groups. It
is also used in hydrogenolysis ( viz dehalogenation, debenzylation) and desulfurisation
reactions. Due to its ability to hydrogenate virtually any type
of functional group Raney Nickel is termed as non-specific
catalyst.
Raney Nickel can
also be used in hydrogenation reactions involving very high
pressure and temperature. Raney Nickel catalyst however cannot
be used for hydrogenation where reaction conditions are acidic
in nature, i.e pH < 5. Catalyst loading may vary from as low
as 0.5 % to as high as 100 % of the substrate and some times
even more depending upon nature of hydrogenation and the
substrates involved.
Raney Nickel
can also be used for dehydrogenation reactions.
Vineeth Chemicals
produces three common varieties of Raney Nickel Catalyst, viz,
fine, medium and coarse based upon particle size of the slurry
which indirectly correspond respectively to high (comparable to
W6), medium (comparable to W3, W4 & W5) and moderate
(comparable to W1, W2) activity catalysts. The quality of Raney
Nickel produced by the company, compares well with the makes of
international repute. Besides, fine, medium and coarse grade,
the company has capability of making Raney Nickel as per
customer’s specification such as very low activity,
non-pyrophoric, neutral pH, low slurry density, high slurry
density, Molybdenum or Chromium promoted catalyst. Our catalysts
are easy to filter and are guarded against small amounts of
oxidants.
The assured shelf
life of the product is three months from the date of
manufacture.
Notable users are
Pesticides, Dyes, Drugs, Perfumery Compounds, Sorbitol, Rubber
additives manufacturers besides host of other fine chemical
manufacturers.
Raney
Nickel being pyrophoric in nature should be handled with great
care. Only skilled and trained persons with adequate safety
measures should be deployed for handling this product.
The
standard packing is 5 Kgs and 10 Kgs in M.S Drums or HDPE Drums.
The packing size however can be tailored to customers specific
requirements.
We
have developed techniques of reactivation of spent catalyst and
the job work is undertaken on commercial basis. Use of
reactivated catalyst can substantially reduce the cost of
hydrogenation. It should however be noted that use of
reactivated Raney Nickel Catalyst should be restricted to the
specific products alone from which the spent got generated.
Further, when the intention is to recycle the catalyst or get it
reactivated, it should always be kept submerged under water or
solvent and pH be maintained ~ 10.
For
further details please feel free to contact General Manager,
Vineeth Chemicals.
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