Abstract: An End of Service Life (ESLI) and Residual Life Indicator (RLI), for gas masks and other filters. The indicator includes a solid conduit with one end closed by a transparent material and the other by a porous material which allows gas to permeate through it. In one implementation of the ESLI, a fine powder that can react chromogenically is placed in the conduit. The powder is free to move in the conduit, but it cannot escape. The porous end of the conduit is inserted into the filter to the desired depth. When a target gas reaches the porous end, it enters the conduit, reacts chromogenically with the powder and changes color. The powder can be viewed through the conduit by tilting the filter to cause the powder to gravitate into the transparent end. A color chart is attached to the filter near the transparent end to facilitate a determination of whether the chromogenic powder has undergone a color change or not.

Abstract: The present invention relates to systems and methods for the rapid and reliable detection of acutely dangerous levels of poisons in liquid food and/or water samples. The systems preferably include an inexpensive and disposable laminated card including a dry chemical system of detection.

Abstract: The present invention entails a coal demineralization and depyritization process which produces coal with extremely low mineral (ash) and pyrite contents. Essentially the present process calls for the chemical treatment of the coal surface first, followed by a physical separation step in which the minerals are separated from the coal. The chemical step comprises of subjecting and treating the coal surface with an alcohol composition such as methanol for a selected period of time and at a selected temperature within a reactor in the presence of an acid catalyst. This chemical step makes the coal surface non-polar mainly by reacting the alcoholic and carboxylic groups. In particular, this chemical step is designed to reduce the surface forces between the organic and inorganic phases and consequently facilitate the mineral separation. After the chemical treatment of the coal, actual separation of the minerals can be achieved by one of many conventional physical separation process.

Abstract: A desulfurization process is described which consists of heating an organic hydrocarbon like coal or bitumen in a stream of a gaseous or liquid trapping material for hydrogen sulfide (H.sub.2 S). The organic sulfur in the hydrocarbon decomposes and releases H.sub.2 S which reacts with the trapping material to form a metastable sulfur compound. The resulting gaseous or liquid stream is recovered and decomposed in a subsequent step to form H.sub.2 S and to the original trapping material. The trapping material is recovered and recirculated into the reactor. Ethylene, propylene and other olefins, as well as aldehydes and ketones are found to be excellent trapping materials.