High capacity regenerable sorbent for removal of mercury from flue gas

A sorbent particle comprising:

• a montmorillonite having a plurality of ion-exchange sites;
• a plurality of polyvalent metal ions exchanged at some of said ion-exchange sites;
• and
• a plurality of sulfide ions chemically reacted to at least some of said polyvalent metal ions;
• wherein said sorbent particle is essentially devoid of polysulfides, said sorbent particle has a largest dimension of less than about twenty micrometers and said sorbent particle is operative to capture at least some of the ionic and elemental mercury present in a flue gas containing acid gases to which it is exposed.

A sorbent particle comprising:

• a cryptocrystalline phyllosilicate having a plurality of ion-exchange sites;
• a plurality of polyvalent metal ions exchanged at some of said ion-exchange sites;
• and
• a plurality of sulfide ions chemically reacted to at least some of said polyvalent metal ions;
• wherein said sorbent particle is essentially devoid of polysulfides said sorbent particle is operative to capture at least some of the ionic and elemental mercury present in flue gas to which it is exposed.

A sorbent comprising:

• a phyllosilicate having a plurality of ion-exchange sites;
• a plurality of polyvalent metal ions exchanged at some of said ion-exchange sites;
• and
• a plurality of sulfide ions chemically reacted to at least some of said polyvalent metal ions;
• wherein said sorbent operative to accomplish sustained removal of the ionic and elemental mercury present in an acidic flue gas to which it is exposed.

A sorbent comprising:

• a non-zeolitic, amorphous aluminosilicate having a plurality of ion-exchange sites;
• a plurality of polyvalent metal ions exchanged at some of said ion-exchange sites;
• and
• a plurality of sulfide ions chemically reacted to at least some of said polyvalent metal ions;
• wherein said sorbent is essentially devoid of copper and polysulfides.

An adsorbent composition for use in the adsorption of ionic and elemental mercury consisting essentially of:

• a non-zeolitic aluminosilicate support material having cation sites, the material being selected from the class consisting of vermiculites, allophone and montmorillonites;
• a cation selected from the group consisting of antimony, arsenic, bismuth, cadmium, cobalt, gold, indium, iron, lead, manganese, molybdenum, mercury, nickel, platinum, silver, tin, tungsten, titanium, vanadium, zinc, zirconium and mixtures thereof wherein the cation occupies some of the cation sites;
• and
• a sulfide.

An adsorbent composition for use in the adsorption of ionic and elemental mercury consisting essentially of:

• a phyllosilicate support material having cation sites, the material being selected from the class consisting of vermiculites and montmorillonites;
• a cation selected from the group consisting of antimony, arsenic, bismuth, cadmium, cobalt, copper, gold, indium, iron, lead, manganese, molybdenum, mercury, nickel, platinum, silver, tin, tungsten, titanium, vanadium, zinc, zirconium and mixtures thereof wherein the cation occupies some of the cation sites;
• and
• a sulfide.

A sorbent comprising:

• a silicate having a first layered structure selected from the group consisting of
• kaolinite,
• halloysite,
• montmorillonite,
• illite,
• bentonite,
• chlorite, and
• vermiculite;
• impregnated with a metal sulfide having a second layered structure;
• wherein said sorbent is essentially free of polysulfides.

A composition of matter consisting of:

• a hydrated laminar magnesium aluminum ironsilicate having a plurality of ion-exchange sites;
• a polyvalent metal ion derived from a highly acidic solution exchanged at some of said ion-exchange sites;
• and
• a plurality of sulfide ions chemically reacted to some of said polyvalent metal ions.

A composition of matter consisting essentially of:

• montmorillonite having a plurality of ion-exchange sites;
• a polyvalent metal ion exchanged at some of said ion-exchange sites;
• and
• a plurality of sulfide ions chemically reacted to said polyvalent metal ions;
• in which each said sulfide ion has the formula Sx−2 wherein x is 1.

A composition of matter made by combining:

• phyllosilicate substrate material having a plurality of ion-exchange sites at which cations are exchangeable;
• a plurality of polyvalent metal ions derived from a highly acidic solution that are exchanged at some of said ion-exchange sites;
• and
• a plurality of sulfide ions which are chemically reactable with some of said polyvalent metal ions.

A composition made by combining effective amounts of:

• means for supporting having a first layered structure and a plurality of ion-exchange sites at which cations are exchangeable;
• a plurality of polyvalent metal ions which are reversibly substituted at some of said ion-exchange sites;
• and
• a plurality of sulfide ions which are chemically reacted to some of said polyvalent metal ions to produce a second layered structure having an inter-layer spacing of about five nanometers;
• wherein said composition comprises essentially no polysulfide ions and is capable of removing mercury from a gas stream containing trace amounts of acid gases.

A composition made by combining effective amounts of:

• a synthetic montmorillinite having a plurality of ion-exchange sites at which cations are exchangeable;
• a plurality of polyvalent metal ions in a highly acidic solution which are reversibly substituted at some of said ion-exchange sites;
• and
• a plurality of sulfide ions that are other than copper ions which are chemically reacted to some of said polyvalent metal ions;
• wherein said composition is essentially devoid of polysulfide ions and is capable of sorbing mercury from a gas.

An adsorbent composition for use in the adsorption of elemental mercury consisting essentially of:

• a support material selected from the class consisting of
• phyllosilicates;
• a cation selected from the group consisting of
• a bivalent tin ion,
• a tetravalent tin ion,
• a bivalent iron ion,
• a trivalent iron ion,
• a titanium ion,
• a manganese ion,
• a zirconium ion,
• a vanadium ion,
• a zinc ion,
• a nickel ion,
• a bismuth ion,
• a cobalt ion,
• and a molybdenum ion;
• and
• a sulfide;
• wherein said composition is essentially devoid of polysulfides.

A process for the preparation of sorbent particles for ionic and elemental mercury comprising:

• (a) reducing the size of a phyllosilicate support material having cation sites, the material being selected from the class consisting of vermiculites and montmorillonites, to a particle having a largest dimension of less than about twenty micrometers;
• (b) providing the particle of step (a) with at least one cation capable of forming an insoluble sulfide and selected from the group consisting of antimony arsenic, bismuth, cadmium, cobalt, gold, indium, iron, lead, manganese, molybdenum, mercury, nickel, platinum, silver, tin, tungsten, titanium, vanadium, zinc, zirconium and mixtures thereof;
• and
• (c) contacting the cation-containing particle of step (b) with a solution containing a sulfide-forming species and devoid of a polysulfide-forming species to produce a sorbent particle that is operative to capture at least some of the ionic and elemental mercury present in flue gas containing trace amounts of acid gas species to which it is exposed.

A process for producing a sorbent particle comprising:

• reducing the size of a phyllosilicate material to produce a phyllosilicate particle having a largest dimension of less than about twenty micrometers;
• contacting the phyllosilicate particle with a highly acidic solution containing a plurality of polyvalent metal ions other than copper ions to produce an exchanged phyllosilicate particle;
• separating the exchanged phyllosilicate particle from the solution;
• contacting the exchanged phyllosilicate particle with a fluid containing a plurality of sulfide ions and devoid of polysulfide ions to produce an amended phyllosilicate particle;
• and
• separating the amended phyllosilicate particle from the fluid to produce a sorbent particle that is operative to capture at least some of the ionic and elemental mercury present in flue gas to which it is exposed.

A process for producing a sorbent particle comprising:

• reducing the size of a vermiculite material to produce a vermiculite particle having a first layered structure and a largest dimension of less than about twenty micrometers;
• contacting the vermiculite particle with a solution containing a plurality of polyvalent metal ions to produce an exchanged vermiculite particle;
• separating the exchanged vermiculite particle from the solution;
• contacting the exchanged vermiculite particle with a fluid containing a plurality of sulfide ions and devoid of polysulfide ions to produce an amended vermiculite particle containing an amendment having a second layered structure;
• and
• separating the amended vermiculite particle from the fluid to produce a sorbent particle that is operative to capture at least some of the ionic and elemental mercury present in flue gas to which it is exposed.

A process for producing a sorbent particle comprising:

• reducing the size of a montmorillonite material to produce a montmorillonite particle having a largest dimension of less than about twenty micrometers;
• contacting the montmorillonite particle with a solution containing a plurality of polyvalent metal ions to produce an exchanged montmorillonite particle;
• separating the exchanged montmorillonite particle from the solution;
• contacting the exchanged montmorillonite particle with a fluid containing a plurality of sulfide ions and devoid of polysulfide ions to produce an amended montmorillonite particle;
• and
• separating the amended montmorillonite particle from the fluid to produce a sorbent particle that is operative to capture at least some of the ionic and elemental mercury present in flue gas to which it is exposed.

A process for producing a sorbent comprising:

• contacting a phyllosilicate substrate material with a solution containing a polyvalent metal ion to produce an exchanged phyllosilicate;
• separating the exchanged phyllosilicate from the solution;
• contacting the exchanged phyllosilicate with a fluid containing a sulfide ion other than a polysulfide ion to produce an amended phyllosilicate;
• separating the amended phyllosilicate from the fluid to produce a sorbent.

A sorbent production system comprising:

• means for contacting a silicate substrate material with a solution containing a polyvalent metal ion other than a copper ion to produce an exchanged silicate;
• means for separating the exchanged silicate from the solution;
• means for contacting the exchanged silicate with a fluid containing a sulfide ion being devoid of a polysulfide ion to produce an amended silicate;
• and
• means for separating the amended silicate from the fluid to produce a sorbent.