Method for preparing a sorbent

Patent metadata

Field	Value
Publication number	US-2016279596-A1
Application number	US-201415036817-A
Country	US
Kind code	A1
Filing date	Dec 4, 2014
Priority date	Dec 18, 2013
Publication date	Sep 29, 2016
Grant date	—

Abstract

A method for preparing a sorbent precursor, which may be sulphided and used to remove heavy metals such as mercury from fluid streams, includes the steps of:
(i) mixing together an inert particulate support material and one or more binders to form a support mixture, (ii) shaping the support mixture by granulation in a granulator to form agglomerates, (iii) coating the agglomerates with a coating mixture powder including a particulate copper compound and one or more binders to form a coated agglomerate, and (iv) drying the coated agglomerate to form a dried sorbent precursor.

First claim

1 - 25 . (canceled)

26 . A method for preparing a sorbent precursor comprising the steps of:
(i) mixing together an inert particulate support material and one or more binders to form a support mixture, (ii) shaping the support mixture by granulation in a granulator to form agglomerates, (iii) coating the agglomerates with a coating mixture powder comprising a particulate copper compound and one or more binders to form a coated agglomerate, and (iv) drying the coated agglomerate to form a dried sorbent precursor.

27 . The method according to claim 26 wherein the inert particulate support material is selected from the group consisting of alumina, metal-aluminate, silicon carbide, silica, titania, zirconia, zinc oxide, aluminosilicates, zeolites, metal carbonate, carbon, or a mixture thereof.

28 . The method according to claim 26 wherein the inert particulate support material is selected from aluminas and hydrated aluminas.

29 . The method according to claim 26 wherein the inert particulate support material is in the form of a powder with a D 50 particle size in the range 1-100 μm.

30 . The method according to claim 26 wherein the binder used to prepare the agglomerates is selected from clay binders, cement binders and organic polymer binders and mixtures thereof.

31 . The method according to claim 26 wherein agglomerates have a diameter in the range 1-15 mm.

32 . The method according to claim 26 wherein the particulate copper compound is one or more compounds selected from copper oxide, basic copper carbonate, and precipitated materials comprising copper basic carbonate and zinc basic carbonate.

33 . The method according to claim 26 wherein the particulate copper compound is in the form of a powder with an average particle size, [D 50 ], in the range 5-100 μm.

34 . The method according to claim 26 wherein the copper content of the dried sorbent precursor is in the range 0.5-30% by weight (expressed as copper present in the dried material).

35 . The method according to claim 26 wherein the copper compound is present as a layer on the surface of the agglomerate and the thickness of the layer in the dried sorbent precursor is in the range 1 to 1000 μm (micrometres).

36 . The method according to claim 26 wherein the sorbent precursor comprises a mixture of a particulate basic copper carbonate and a clay binder, as a surface layer of 1 to 1000 μm thickness coated on the surface of agglomerates formed from a particulate hydrated alumina support material, which is bound together with a cement binder and a clay binder.

37 . The method according to claim 26 wherein the agglomerates are coated by adding the coating mixture to the agglomerates in the granulator.

38 . The method according to claim 26 wherein the coated agglomerate is dried at 70-150° C.

39 . The method for preparing a sorbent comprising preparing a sorbent precursor according to claim 26 and subjecting the dried sorbent precursor to a sulphiding step to convert the copper compound to copper sulphide.

40 . The method according to claim 39 wherein the sulphiding step is performed by reacting the copper compound with a sulphur compound selected from hydrogen sulphide, alkali metal sulphide, ammonium sulphide, elemental sulphur or a polysulphide.

41 . The method according to claim 39 wherein the sulphiding step is performed using hydrogen sulphide at a concentration in the range 0.1 to 5% by volume in an inert gas.

42 . The method according to claim 39 wherein the sulphiding step is performed on the dried sorbent precursor composition ex-situ in a sulphiding vessel through which a sulphiding agent is passed, or performed in situ, in which case the dried sorbent precursor composition is installed and undergoes sulphidation in the vessel in which it is used to absorb heavy metals.

43 . A sorbent precursor obtainable by the method of claim 26 .

44 . A sorbent obtainable by the method of claim 39 .

45 . A process for removing a heavy metal from a fluid stream comprising contacting the fluid stream with a sorbent according to claim 44 .

Assignees

• Johnson Matthey Plc

Inventors

• Evans Matthew James
• Foran Paul Thomas
• Lunn Matthew David Gwydion

Classifications

• B01J20/2803

  Sorbents comprising a binder, e.g. for forming aggregated, agglomerated or granulated products · CPC title

• B01J20/08

  comprising aluminium oxide or hydroxide; comprising bauxite · CPC title

• B01D2258/05

  Biogas · CPC title

• B01J20/3042

  Use of binding agents; addition of materials ameliorating the mechanical properties of the produced sorbent · CPC title

• B01D53/64

  Heavy metals or compounds thereof, e.g. mercury · CPC title