Abstract: A method and apparatus for performing solid phase extraction (SPE) on a fluid that contains solubles and suspended solids. The method includes: (a) providing a volume of fluid that contains solubles and suspended solids, (b) processing the volume of fluid to extract solubles therefrom by the steps comprising: (i) passing a first portion of the volume of fluid through a SPE medium that has first and second sides, the first portion of the volume of fluid passing through the SPE medium from the first side to the second side; and then (ii) passing a second portion of the volume of fluid through the SPE medium from the second side to the first side; and (c) repeating step (b) a plurality of times such that no substantial amount of the suspended solids is removed from the processed volume of fluid and solubles are retained on the SPE medium. The apparatus includes a conduit, a SPE medium located in the conduit, and a fluid flow direction altering mechanism or a SPE rotating mechanism.

Abstract: Composite reactive articles are useful for quantifying cyanide ions in solution. The composite reactive articles can be porous reactive supports comprising an inert substrate having immobilized thereon finely divided gold. The porous reactive supports can be particulate, porous fibrous membranes, or solution-cast membranes. Alternatively, the composite reactive articles can comprise porous fibrous membranes having enmeshed therein the aforementioned porous supports which can be in particulate or fibrous forms.

Abstract: A particle loaded, porous, fibrous compressed or fused article comprises a nonwoven fibrous polymeric web, which preferably is thermoplastic, melt-extrudable, and pressure-fusible blown microfibrous web, and sorptive particles enmeshed in said web, the particle loaded fibrous article has a Gurley number of at least two seconds, and the article is useful in separation science. A method of preparation of the article and method of use is also disclosed.

Abstract: A method of removing olefinic impurity, such as perfluoroisobutylene, from fluoroperhalocarbon liquid, such as perfluorinated liquid, comprising the step of contacting the fluoroperhalocarbon liquid with a body of particles comprising particles selected from the group consisting of alumina, alkali metal oxide, alkali metal hydroxide, alkaline earth oxide, alkaline earth hydroxide, silicon oxide, tin oxide, zinc oxide, alkaline earth basic carbonate, and alkaline earth basic phosphate, transition metal oxide particles and mixtures thereof.

Abstract: A method for isolating an environmentally hazardous organic contaminant from a fluid utilizes a solid phase extraction medium comprises a PTFE fibril matrix, and sorptive particles enmeshed in said matrix comprising more than 30 and up to 100 weight percent of porous organic particles, and less than 70 to 0 weight percent of porous (organic-coated or uncoated) inorganic particles, the ratio of sorptive particles to PTFE being in the range of 40:1 to 1:4 by weight. The extraction medium is useful in pesticide, phenolics, and residue of explosives separations. The separations can be efficiently performed in a stacked disk format.

Abstract: A composite article comprising, in the unexpanded form, a fibrillated PTFE matrix and a combination of energy expandable hollow polymeric particles and sorptive particles, which composite, on applying energy such as steam, heat, or laser energy, provides an expanded article having increased void volume and decreased density. The expanded articles are porous and efficient articles for separation and purification applications. In flat or rolled form, the composite article can be used in separation devices.

Abstract: A composite article comprising, in the unexpanded form, a fibrillated PTFE matrix and a combination of energy expandable hollow polymeric particles and sorptive particles, which composite, on applying energy such as steam, heat, or laser energy, provides an expanded article having increased void volume and decreased density. The expanded articles are porous and efficient articles for separation and purification applications. In flat or rolled form, the composite article can be used in separation devices.

Abstract: A composite article having controlled void volume and mean pore size comprises:(a) polytetrafluoroethylene (PTFE) fibril matrix, and(b) insoluble, non-swellable sorptive particles enmeshed in said matrix, the ratio of non-swellable sorptive particles to PTFE is in the range of 40:1 to 1:4 by weight, the composite article having a porosity in the range of 30 to 80 percent void volume and a mean pore size in the range of 0.3 to 5 micrometers, preferably with at least 90 percent of pores having a size less than 3.6 micrometers.The article is prepared by incorporating lubricant in the precursor admixture in an amount sufficient to exceed the lubricant sorptive capacity of the particles by at least 3 weight percent and up to an amount at which the mass loses its integrity.

Abstract: A composite article having controlled void volume and mean pore size comprises:(a) polytetrafluoroethylene (PTFE) fibril matrix, and(b) insoluble, non-swellable sorptive particles enmeshed in said matrix, the ratio of non-swellable sorptive particles to PTFE is in the range of 40:1 to 1:4 by weight, the composite article having a porosity in the range of 30 to 80 percent void volume and a mean pore size in the range of 0.3 to 5 micrometers, preferably with at least 90 percent of pores having a size less than 3.6 micrometers.The article is prepared by incorporating lubricant in the precursor admixture in an amount sufficient to exceed the lubricant sorptive capacity of the particles by at least 3 weight percent and up to an amount at which the mass loses its integrity.

Abstract: A composite article having controlled void volume and mean pore size comprises:(a) polytetrafluoroethylene (PTFE) fibril matrix, and(b) insoluble, non-swellable sorptive particles enmeshed in said matrix, the ratio of non-swellable sorptive particles to PTFE is in the range of 40:1 to 1:4 by weight, the composite article having a porosity in the range of 30 to 80 percent void volume and a mean pore size in the range of 0.3 to 5 micrometers, preferably with at least 90 percent of pores having a size less than 3.6 micrometers.The article is prepared by incorporating lubricant in the precursor admixture in an amount sufficient to exceed the lubricant sorptive capacity of the particles by at least 3 weight percent and up to an amount at which the mass loses its integrity.

Abstract: A medium for electrophoresis comprises:(a) a polytetrafluoroethylene (PTFE) fibril matrix, and(b) particulate, electrically mobile ions, and sufficient liquid in the interstitial spaces of said matrix to allow for ion transport,the ratio of said particulate to PTFE being in the range of 99:1 to 4:1 by weight, and said ions being present in said liquid in an amount to provide a solution of concentration in the range of 1 to 1000 millimolar.Preferably the medium is self supporting.

Abstract: A composite chromatographic sheet-like article is prepared by the steps comprising blending one or more non-swellable sorptive hydrophobic particulate materials in the presence of an amount of polar organic masking agent sufficient to allow rapid wetting of the surface of the particulate and in the presence of sufficient lubricant water to exceed the sorptive capacity of the particulate, provided that the volume ratio of water to masking agent does not exceed 3:1, adding with stirring an aqueous emulsion of polytetrafluoroethylene so that the resulting mass has a dough-like consistency, mixing the mass in an intensive mixer at a temperature between 50 C. and 100 C. for a time sufficient to cause fibrillation of the polytetrafluoroethylene particles, biaxially calendering the mass, while maintaining water at a level near the absorptive capacity of the particulate, between a gap in the calendering rolls maintained at about 50 C. to about 100 C.

Abstract: A composite chromatographic article comprising: (a) a polytetrafluoroethylene fibril matrix, and(b) non-swellable sorptive particles enmeshed in said matrix, the ratio of non-swellable sorptive particles to polytetrafluoroethylene being in the range of 19:1 to 4:1 by weight, said composite article having a net surface energy in the range of 20 to 300 milliNewtons per meter.

Abstract: A composite chromatographic article comprising:(a) a polytetrafluoroethylene fibril matrix, and(b) non-swellable sorptive particles enmeshed in said matrix, the ration of non-swellable sorptive particles to polytetrafluoroethylene being in the range of 19:1 to 4:1 by weight, said composite article having a net surface energy in the range of 20 to 300 milliNewtons per meter.

Abstract: An apparatus and method for analyzing a sample of an inorganic or organic material, wherein the sample is in a discharge tube within a plasma cavity interfaced to an analytical device and a high frequency-sustained radiation-induced excitation plasma is initiated and sustained in the plasma cavity, which plasma is capable of causing the sample to pyrolyze and emit radiation, which emitted radiation or resulting atomic and molecular constituents may be analyzed,the improvement comprising:means for fixing or immobilizing the sample at a position spaced apart from the plasma, andmeans for elongating the plasma so as to cause it to encompass the sample.