Abstract: Metal sulfides having a micro-porous structure are disclosed for use as sorbents for removal of mercury from flue gas. Systems are disclosed for making and using micro-porous particulates at least partially composed of alkaline earth metal and transition metal sulfides as sorbents. Calcium sulfide micro-porous powders derived from the high temperature reduction of calcium sulfate and calcium sulfite are disclosed to be reactive substrates for a group of sorbents for adsorption of mercury from the myriad of coal combustion flue gases produced by the utilities industry, as well as from natural gas and gaseous and liquid hydrocarbons. Controlled addition of one or more of polyvalent metal ions, chloride ions, polysulfide ions, and sulfur to the micro-porous calcium sulfide substrate produces the sorbent. The sorbents are useful for cost-effectively adsorbing elemental mercury and oxidized mercury species such as mercuric chloride from flue gases, including those containing acid gases (e.g., SO.sub.2, NO and NO.

Abstract: Novel organic compositions for removing dyes from the surface of polymeric fibers are disclosed. The method for dye removal from the surface of fibers includes contacting the fibers with a non-aqueous ester stripping composition preferably containing at least one cyclic ester and optionally containing a surfactant, an alcohol, or both. The process of the present invention is especially useful for removing color from dyed polyamide fibers as part of a recycling process for such materials.

Abstract: A process to decompose polyester by heating in the presence of a cyclic ester solvent is disclosed. Physically separated polyester-rich waste can be recycled by forming an admixture with a cyclic ester solvent, preferably propylene carbonate, and heating the admixture to a temperature above about 215 degrees Celsius. The polyester is decomposed into monomers and oligomers which are soluble in ethylene carbonate or propylene carbonate at ambient temperature. The polyester decomposition products are useful as components of an industrial solvent or as inputs to other chemical processes.

Abstract: In the recycling of Nylon 6 and Nylon 6,6 polyamides from post-consumer or post-industrial waste, a process is disclosed to separate Nylon 6 and Nylon 6,6 polyamides from commingled polyolefin waste components, particularly polypropylene, by admixing the waste with an ester solvent composition and heating the admixture to a temperature above the melting temperature of the contained polyolefins to form an ester solvent composition further containing dissolved polyamide polymer and a separate immiscible liquid polyolefin phase. The ester solvent composition preferably contains ethylene carbonate, propylene carbonate, butylene carbonate, or mixtures thereof.