Sorbent components containing halogen, calcium, alumina, and silica are used in combination during coal combustion to produce environmental benefits. Sorbents such as calcium bromide are added to the coal ahead of combustion and other components are added into the flame or downstream of the flame, preferably at minimum temperatures to assure complete formation of the refractory structures that result in various advantages of the methods. When used together, the components reduce emissions of elemental and oxidized mercury; increase the level of Hg, As, Pb, and/or Cl in the coal ash; decrease the levels of leachable heavy metals (such as Hg) in the ash, preferably to levels below the detectable limits; and make a highly cementitious ash product.

Sorbent compositions containing calcium and iodine are added to coal to mitigate the release of mercury and/or other harmful elements into the environment during combustion of coal containing natural levels of mercury.

Sorbent compositions containing calcium and iodine are added to coal to mitigate the release of mercury and/or other harmful elements into the environment during combustion of coal containing natural levels of mercury.

A fuel element adapted for use in a smoking article is provided, the fuel element including a combustible carbonaceous material in an amount of at least 25% by dry weight, based on the weight of the fuel element, and a particulate ignition aid dispersed throughout the fuel element and selected from ceramic particles, cellulose particles, fullerenes, impregnated activated carbon particles, inorganic salts, and combinations thereof, wherein the average particle size of the ignition aid is less than about 1,000 microns. Also provided are elongate smoking articles having a lighting end and an opposed mouth end, and including the above-noted fuel element configured for ignition of the lighting end.

A fuel element adapted for use in a smoking article is provided, the fuel element including a combustible carbonaceous material in an amount of at least 25% by dry weight, based on the weight of the fuel element, and a particulate ignition aid dispersed throughout the fuel element and selected from ceramic particles, cellulose particles, fullerenes, impregnated activated carbon particles, inorganic salts, and combinations thereof, wherein the average particle size of the ignition aid is less than about 1,000 microns. Also provided are elongate smoking articles having a lighting end and an opposed mouth end, and including the above-noted fuel element configured for ignition of the lighting end.

Disclosed is a catalyst for desulfurization, including (a) an oxide selected from among SiO.sub.2, Al.sub.2O.sub.3, Fe.sub.2O.sub.3, TiO.sub.2, MgO, MnO, CaO, Na.sub.2O, K.sub.2O and P.sub.2O.sub.3, (b) a metal selected from among Li, Cr, Co, Ni, Cu, Zn, Ga, Sr, Cd and Pb, and (c) a liquid compound selected from among sodium tetraborate (Na.sub.2B.sub.4O.sub.7.10H.sub.2O), sodium hydroxide (NaOH), sodium silicate (Na.sub.2SiO.sub.3) and hydrogen peroxide (H.sub.2O.sub.2). The catalyst of the invention has a 2:1 type layered structure in which one octahedral layer is interposed between two tetrahedral layers and which has a net negative charge due to occupation of only two of three positively charged sites in the octahedral layer, and the catalyst for desulfurization is provided in the form of a metal chelate compound through chelation with a metal ion, whereby sulfur oxide (SO.sub.x) can be adsorbed and removed at high efficiency upon combustion of a combustible substance.

Disclosed is a catalyst for desulfurization, including (a) an oxide selected from among SiO.sub.2, Al.sub.2O.sub.3, Fe.sub.2O.sub.3, TiO.sub.2, MgO, MnO, CaO, Na.sub.2O, K.sub.2O and P.sub.2O.sub.3, (b) a metal selected from among Li, Cr, Co, Ni, Cu, Zn, Ga, Sr, Cd and Pb, and (c) a liquid compound selected from among sodium tetraborate (Na.sub.2B.sub.4O.sub.7.10H.sub.2O), sodium hydroxide (NaOH), sodium silicate (Na.sub.2SiO.sub.3) and hydrogen peroxide (H.sub.2O.sub.2). The catalyst of the invention has a 2:1 type layered structure in which one octahedral layer is interposed between two tetrahedral layers and which has a net negative charge due to occupation of only two of three positively charged sites in the octahedral layer, and the catalyst for desulfurization is provided in the form of a metal chelate compound through chelation with a metal ion, whereby sulfur oxide (SO.sub.x) can be adsorbed and removed at high efficiency upon combustion of a combustible substance.

Disclosed is a desulfurization system using a catalyst for desulfurization, including a coal feed unit for conveying a combustible substance, a spray unit for spraying a catalyst for desulfurization, a coal pulverization unit for pulverizing the combustible substance conveyed from the coal feed unit, and a combustion unit for combusting the pulverized combustible substance, wherein during transfer of the combustible substance from the coal feed unit to the coal pulverization unit, the catalyst for desulfurization is sprayed using the spray unit and is mixed with the combustible substance. The desulfurization system of the invention can be simply and easily applied to various combustion facilities because, during the transfer of the combustible substance from the coal feed unit to the coal pulverization unit, the catalyst for desulfurization is sprayed and is mixed with the combustible substance, thereby efficiently reducing sulfur oxide (SO.sub.x) emission due to combustion of fossil fuel.

An additive composition for a marine fuel or a heating oil comprising a stabilized colloidal dispersion of catalytic metal particles, a neutral or overbased alkaline earth metal detergent and a carrier fluid miscible with a marine fuel oil, a heavy fuel oil, a marine distillate fuel, and/or a residual fuel oil. Also provided are marine fuel and/or heating oil compositions having the additive composition described above and associated methods and uses.

An additive composition for a marine fuel or a heating oil comprising a stabilized colloidal dispersion of catalytic metal particles, a neutral or overbased alkaline earth metal detergent and a carrier fluid miscible with a marine fuel oil, a heavy fuel oil, a marine distillate fuel, and/or a residual fuel oil. Also provided are marine fuel and/or heating oil compositions having the additive composition described above and associated methods and uses.