Abstract: The present disclosure is a tape responsive to gases. One version is paper impregnated with lead acetate, a backing layer of impervious sheet material, and a top face pervious, transparent layer. The top layer retards gas exposure and expands the range of sensitivity. The top layer is preferably pervious, transparent and has a thickness and width to control exposure.

Abstract: The method measures hydrogen sulfide concentrations in hydride gases in a sealed vessel. The sealed vessel has a gas inlet to receive a stream of hydride gas, a gas outlet to remove the stream of hydride gas and a metal acetate substrate. The stream of hydride gas contains a concentration of hydrogen sulfide gas. Introducing the stream of hydride gas through the gas inlet contacts the acetate substrate with the stream of hydride gas. Reacting the hydrogen sulfide gas contained in the stream of hydride gas with the acetate substrate modifies optical properties of the acetate substrate. Then measuring the optical properties of the acetate substrate determines the concentration of the hydrogen sulfide gas contained in the stream of hydride gas.

Abstract: A kit is provided for testing a gas produced from a sample for an absolute amount of a hydrogen sulfide. The kit includes a vessel for receiving the sample to be tested. The vessel includes one or more gas flow passages through which gas within the vessel can leave the vessel. The kit also includes one or more testing tubes. Each testing tube includes a lumen through which gas can flow. The lumen includes a column of medium observable from outside the testing tube and has a length which changes in appearance in proportion to the amount of hydrogen sulfide which has passed through the testing tube. Graduations are included on the one or more testing tubes for indicating the length of the column of medium whose appearance has changed. The kit also includes a coupling mechanism for coupling the one or more testing tubes with the one or more gas flow passages such that gas leaving the vessel passes through the one or more testing tubes.

Abstract: A method which enables the sulphur and/or hydrogen contained in a low quantity in hydrogen sulphide to be prepared:1) the H.sub.2 S is oxidized at a temperature and for a duration selected to obtain full oxidation of the H.sub.2 S into SO.sub.2 and at least two products are obtained at the end of this step: SO.sub.2 and H.sub.2 O,2) The two products SO.sub.2 and H.sub.2 O obtained at the end of step 1) are separated,3) the isotope of the sulphur contained in the sulphur dioxide obtained during step 2) is measured and/or4) the H.sub.2 O obtained during step 2) is brought into contact with an agent capable of reducing the water to hydrogen form and5) the isotope of the hydrogen is measured.

Abstract: The selectivity of response of resistive gas sensors to specific gases or vapors is improved by the selection of specified gas-sensitive materials which are not previously known for the applications described, which include detection of hydrocarbons in the presence of CO, H.sub.2 S, SO.sub.2, chlorine, NO.sub.2, CO.sub.2 (especially in low concentrations), CFC's, ammonia, free oxygen by determination of partial pressures, and numerous organic gases and vapors.

Abstract: A hydrogen sulfide analyzer that continuously samples waste water from a waste stream or reservoir and measures the concentration of purgeable H.sub.2 S present (H.sub.2 SP) This information, when combined with the volume of water present, provides a control quality signal that regulates the feed rate of the destructor chemical into the waste stream. This results in chemical savings for the user. A second result is the reduction in odor complaints and the corrosion problems associated with H.sub.2 S emissions. The analyzer measures only the purgeable H.sub.2 S contained in the liquid sample. The analyzer violently agitates the sample containing dissolved H.sub.2 S in solution to simulate actual conditions at points of agitation in the waste water stream. It also provides nearly optimal partial pressure conditions for the H.sub.2 S to exit the solution as a free gas. Any H.sub.

Abstract: A process and apparatus are disclosed for the detection and measurement of sulfur in both organic and inorganic sulfur-containing compounds. The process includes admixing a sample including a sulfur-containing compound with oxygen, and then exposing the mixture to a source of combustion causing heat in the presence of a combustion supporting reducing agent at a combustion site. The resulting gaseous combustion products are vacuum extracted from the combustion site, and then directed into a darkened low pressure chamber. The combustion products in the low pressure chamber are then contacted with ozone, with the result that the sulfur combustion products are converted to chemiluminescent sulfur dioxide. The emitted chemiluminescence is then detected, and may be measured to provide a quantitative indication of the amount of sulfur in the original sample. The preferred source of oxygen is air, the preferred form of combustion heat is a flame, and the preferred form of reducing agent is hydrogen gas.

Abstract: A field test kit for determining quantity of hydrogen sulfide in a liquid st sample. The test kit includes a test container with an opening for a liquid test sample containing hydrogen sulfide gas and a cap provided over the opening. The cap has calorimetric particulate indicator on its top inside surface. A silicone barrier disposed over the indicator protects the indicator from contact with the test sample.

Abstract: The invention is directed to a method for determining the portion of a gaseous or vaporous component in a gas mixture utilizing a detecting substance which can enter into a chemical reaction with the component to produce a coloration of the detecting substance and utilizing a device for evaluating the coloration. The method includes the steps of: passing the gas mixture at a constant volume flow through a channel containing the detecting substance; detecting a reflectance signal I(t) within a defined spatially fixed length segment of the channel; determining a slope .DELTA.I/.DELTA.t at the start of the chemical reaction during a time interval .DELTA.t in which the detecting substance is present in excess; determining a saturation reflectance signal I.sup.100% toward the end of the chemical reaction which corresponds to an almost complete chemical conversion of the detecting substance within the length segment; and, determining a normalized slope in correspondence to the formal relationship: .DELTA.I/(I.sup.

Abstract: An apparatus and method for detecting a leak by mixing an amount of odorant ith the contents of a sealed container. An amount of odorant having a detectable odor is mixed with the contents of a sealed container. The sealed container with the odorant is placed within a detection zone which is monitored to detect the presence of the odorant which would indicate leakage of the container's contents. The detection zone defines an area within which leakage of the contents will produce a detectable quantity of the odorant. The odorant may be a gas. Preferred odorants are selected from the group consisting of sulfides, cyclic sulfides and mercaptans. In a sealed light source device having radioactive tritium gas, the preferred odorant is hydrogen sulfide which is detectable by individuals in concentrations of at least 5 parts-per-billion (ppb). Individuals, which may be part of a scheduled roving sentry or a patrol, monitor for the presence of the odorant in the detection zone.

Abstract: Viscous, liquid hexafluoroisopropanol-siloxane polymers having the basic structure: ##STR1## wherein R.sub.1 is a monovalent hydrocarbon radical selected from the group consisting of C.sub.1 -C.sub.6 alkyl groups; cyclohexyl groups and phenyl groups;R.sub.2 is ##STR2## wherein m=1 to 4; and n is an integer greater than 1, are useful for rapid, reversible vapor sorption, especially for hydrogen bond accepting vapors.

Abstract: A gas analyzer system for providing a spectroscopic analysis of the sample gas. This analysis is accomplished by first introducing the sample gas into the inlet of the system and transporting it to a spectral analyzer. The sample gas is then spectrally analyzed and the analyzer outputs a signal indicative of a radiation intensity spectrum associated with the analyzed sample gas. A processing unit uses the analyzer signal to detect the presence of one or more prescribed gases and to determine the concentration of each of the prescribed gases in the sample gas. Next, the reacting agent is supplied to the sample gas to convert one or more gases whose presence in the sample gas cannot be detected via spectral analysis due to the masking effects other gases present in the sample gas. The masked gases are converted to secondary gases at least one of which is readily detectable via spectral analysis.

Abstract: A scrubber apparatus and controller includes an outlet gas sensor, and a processor operatively connected to the outlet gas sensor and a treatment chemical supply pump for controlling a level of treatment chemical in scrubbing solution responsive to the sensed undesired constituent, such as hydrogen sulfide and/or other odorous gases associated with wastewater. Accordingly, the controller enhances reduction of the undesired constituent in the gas being treated and while conserving consumption of treatment chemical. To enhance the operating life of the outlet and inlet gas sensors, the processor preferably only periodically exposes the gas sensors to gas, and also periodically supplies purging air to the gas sensors. The controller preferably includes an environmentally resistant housing containing the processor means and the outlet gas sensor. In addition, the inlet gas sensor is also preferably included to provide feed forward control and also to provide a log of both inlet and outlet gas readings.

Abstract: This invention is directed to an improved total sulfur chemiluminescence detection system that uses a dual burner to generate the SO speckles for contact with ozone.

Abstract: Non-toxic combustion decomposition accelerators and processes for their production for elemental analysis. The non-toxic accelerators may be either single component or multicomponent. The single component non-toxic accelerators are glass frit, niobium pentoxide, and inorganic phosphate compounds. The multicomponent accelerators are formed from a combination of the foregoing, and most preferably from (a) one or more of niobium pentoxide, tungsten oxide and mixtures thereof, and (b) one or more of glass frit, inorganic phosphate compounds, and mixtures thereof.

Abstract: A field test kit for determining quantity of hydrogen sulfide in a liquid st sample. The test kit includes a test container with an opening for a liquid test sample containing hydrogen sulfide gas and a cap provided over the opening. The cap has colorimetric particulate indicator on its top inside surface. A silicone barrier disposed over the indicator protects the indicator from contact with the test sample.

Abstract: A system is provided for locating and delineating sea floor occurrences of petroleum seepage, achieved by apparatus for the detection of the resulting abnormal distribution of electrical potential within the affected sediments. The system uses an electrically insulating probe, deployed by steel cable from a ship, for the implantation of numerous electrodes within the sediment at depths between 60 cm and 5 m. Insulated conductors within the probe connect the electrodes to a reference electrode by way of an electrometer which facilitates measurement of the difference in electrical potential between any one of the probe electrodes and the reference electrode. Digital measurements are conducted to an associated acoustic modem and thence to the ship through the water. The system allows rapid assessments of sedimentary electrical conditions over large areas of seafloor by the repeated introduction, utilization, withdrawal, and relocation of the probe.

Abstract: The present invention provides a method for measuring the amount of free sulfurous acid and bound sulfurous acid in a sample using a bacterium belonging to Thiobacillus thiooxidans or Thiobacillus ferrooxidans of in which the sample is treated with acid and/or alkali to give free sulfurous acid alone in the sample. Then, the total amount of free sulfurous acid in the sample is measured by an oxidation reaction of free sulfurous acid to sulfuric acid using a bacterium belonging to Thiobacillus thiooxidans or Thiobacillus ferrooxidans.

Abstract: A system for continuously monitoring the hydrogen sulfide concentration present in the atmosphere above a waste water stream, such as a sewerage stream, and for controlling the amount and time of injecting a specified chemical into the waste water stream in order to control the quantity of hydrogen sulfide which would evaporate into the atmosphere.

Abstract: In a method for carrying out a surface plasmon resonance (SPR) measurement a beam of electromagnetic radiation is directed through a part transparent to it onto a surface of a material layer having been brought on its opposite side in contact with a test material. A change in the intensity of the reflected radiation, caused by the resonance phenomenon, is utilized for analyzing the test material. The material layer is of catalytic material, for example palladium, having a negative real part of the dielectric constant at the used wavelength of the electromagnetic radiation and being capable of catalyzing chemical reactions in which the test material takes part. The measurement is carried out at such a wavelength and angle of incidence of the radiation onto the surface that a change resulting from the material concentration accumulated on the opposite side of the material owing to the catalytic properties is detectable in the intensity of the reflected radiation.

Abstract: An apparatus and method for the generation of a control signal for the optimization of sulfur removal in a Claus process unit comprises oxidizing a portion of the tail gas stream exiting the Claus unit by contacting a portion of the tail gas with an oxygen-containing gas in the presence of a catalyst which oxidizes H.sub.2 S to SO.sub.2, measuring the temperature rise associated with the oxidation reaction, converting the measurement to an appropriate control signal, and using the signal to control the rate of air flow into the Claus unit.

Abstract: This invention relates to a process for the selective determination of the oncentration of a substance dissolved in a solvent by means of an osmosis cell. The osmosis cell according to the invention contains a substance not contained in the solution to be tested, which is either practically insoluble or is impermeable for the membrane. This substance reacts chemically with the substance permeating into the osmosis cell, with a product resulting from it in the cell or with a product resulting from the substance in the solution to be tested and permeating into the cell. Reaction products are thereby formed which produce a pressure in the osmosis cell, which is different from the osmotic pressure of the chemically converted portion of the substance. A pressure increase thereby occurs in the cell, from which the concentration of the substance in the solution to be tested can be determined on the basis of standard values.

Abstract: A selected component of a fluid mixture, for example a reduced sulfur compound vapor in air, is detected by selectively adsorbing the component onto a conductive thin layer of material having a chemical affinity for such component and observing the resultant change of electrical resistivity of the layer. The sensitivity of the detector changes with accumulation of the component on the sensor. The accumulation of the component on the sensor is removed by oxidizing and evolving the component from the sensor to restore the sensor to a linear operating region. The accumulated component is preferably oxidized by reacting the component with ozone. The dynamic range of the sensor is increased by counteracting the tendency for the component to accumulate by continuously feeding back ozone to or controlling the temperature of the sensor so that the sensor operates in a linear region near null.

Abstract: Chlorine and hydrogen sulfide contamination in a local atmosphere is removed by drafting a ventilation flow stream of the contaminated atmosphere over an activated carbon adsorber bed. Saturation of the adsorber bed by adsorbed contaminant occurs as a progressive front advancing along the flow stream direction. One or more chlorine and hydrogen sulfide sensitive monitors signal passage of the saturation front at designated bed depth points. Each monitor is exposed to a small air sample flow from the bed at the respectively designated point. Each sample flow is directed serially over two reactive paper filters: the first being impregnated with 0-toluidine to remove Cl.sub.2 and the second being in impregnated with lead acetate to remove H.sub.2 S. Both filters respond to the respective compounds with a color change. Monitor construction and assembly places both filters side-by-side behind transparent chamber windows for manual observation of the color change without disassembly of the monitor unit.

Abstract: Improved process control is achieved in processes for which it is useful to control variable process conditions based upon on-line determinations of the concentration of weak acids and weak bases, or their soluble salts, in liquid streams of the processes. For example, amine system energy savings and waste treatment system control improvements are taught.

Abstract: A selected component of a fluid mixture, for example a reduced sulfur compound vapor in air, is detected by selectively adsorbing the component onto a conductive thin layer of material having a chemical affinity for such component and observing the resultant change of electrical resistivity of the layer. The sensitivity of the detector changes with accumulation of the component on the sensor. The accumulation of the component on the sensor is removed by oxidizing and evolving the component from the sensor to restore the sensor to a linear operating region. The accumulated component is preferably oxidized by reacting the component with ozone. The dynamic range of the sensor is increased by counteracting the tendency for the component to accumulate by continuously feeding back ozone to or controlling the temperature of the sensor so that the sensor operates in a linear region near null.

Abstract: The present invention relates to a biomimetic sensor for detecting the presence of airborne toxins, such as carbon monoxide, mercury, ethylene oxide, volatile organic materials, and hydrogen sulfide. The biomimetic sensor, which has a functional life of at least one year, comprises a porous, semi-transparent substrate into which is impregnated a self-regenerating chemical sensor reagent. The response of the biomimetic sensor mimics the human response to such toxins, with respect to sensitivity and affinity. The extended functional lifetime of the biomimetic sensor and the mimicking of the human response to the toxins are achieved by the use of a molecular encapsulant that encapsulates at least one component of the chemical sensor reagent.

Abstract: A disposal device for photographic processing waste liquor which concentrates the photographic process waste liquor by evaporation. The disposal device has a gas detecting device for detecting gas which may be generated during the evaporation of the waste liquor and a control device for stopping the evaporation based on the detection of a concentration of a specific gas. The processing method for photographic waste liquor involves evaporating the waste liquor to concentrate it and detecting gases which are generated during the evaporation process. When the concentration of a specific gas reaches a certain level, the evaporation step is halted.

Abstract: The total sulfur content of samples consisting of chemical compounds is determined by the use of gas chromatographic separation of the sulfur and its flame-photometric detection. The samples are subjected to a catalytic reaction in a pipe reactor before the separation whereby all sulfur-containing compounds are completely converted into hydrogen sulfide. The pipe reactor is made from an aluminum oxide material in a purity of at least 99.8% of the corundum type.

Abstract: A selected component of a fluid mixture, for example a reduced sulfur compound vapor in air, is detected by selectively adsorbing the component onto a conductive thin layer of material having a chemical affinity for such component and observing the resultant change of electrical resistivity of the layer. The sensitivity of the detector changes with accumulation of the component on the sensor. The accumulation of the component on the sensor is removed by oxidizing and evolving the component from the sensor to restore the sensor to a linear operating region. The accumulated component is preferably oxidized by reacting the component with ozone. The dynamic range of the sensor is increased by counteracting the tendency for the component to accumulate by continuously feeding back ozone to or controlling the temperature of the sensor so that the sensor operates in a linear region near null.

Abstract: A process for the detection of carbonyl sulfide in a gas such as carbon dioxide is provided. The process comprises providing a known volume of gas to be analyzed and removing any hydrogen sulfide from the gas as by passage through a lead acetate column. The carbonyl sulfide is then converted to hydrogen sulfide. Preferably, this is accomplished by passage of the gas through acidified water and subsequent reaction by contact with an alumina hydrolysis catalyst. The converted H.sub.2 S is then detected and measured. The amount of hydrogen sulfide detected represents an equilmolar amount of carbonyl sulfide present in the original volume of gas.

Abstract: A method and apparatus for monitoring the physical and chemical properties of a sample fluid by measuring an optical signal generated by a fluorescent substance and modulated by an absorber substance. The emission band of the fluorescent substance overlaps the absorption band of the absorber substance, and the degree of overlap is dependent on the physical and chemical properties of the sample fluid. The fluorescent substance and absorber substance are immobilized on a substrate so that an effective number of molecules thereof are sufficiently close for resonant energy transfer to occur, thereby providing highly efficient modulation of the fluorescent emissions of the fluorescent substance by the absorber substance.

Abstract: A single gas analyzer is used for analyzing the concentration of two gaseous components such as hydrogen and chlorine in a blend by responding to the chlorine content in the gas blend there being a UV-type reactor for the formation of hydrochloric acid and the operation is such that the gas to be analyzed alternates between a path in which the reaction has taken place and one in which such a reaction has not taken place, for directly measuring the concentration of the gas with a higher concentration and indirectly the concentration of the gas with the lower concentration by determining the depletion the reaction has caused in the higher concentration gas.

Abstract: Oxygen feed to a Claus plant is controlled by calibrating a hydrocarbon-representative response signal, but not a hydrogen sulfide representative response signal, responsive to the ratio of hydrogen sulfide:sulfur dioxide in effluent from the Claus plant.

Abstract: A process for the rapid extraction, separation, and detection of free and total sulfites in food is disclosed. The process comprises the steps of (a) extracting sulfites from a sample in the presence of a medium having a selected pH to produce an extractant; (b) filtering the extractant; (c) subjecting the filtered extractant to anion exclusion chromatography to produce a sulfite-containing effluent; and (d) detecting the proportion of sulfites in the effluent. The process may be used either to determine free sulfites (by performing extraction in the presence of an acid medium), or to determine total sulfites (by performing extraction in the presence of an alkaline medium). The process of the present invention may be used to determine sulfite levels of 1.0 ppm or less.

Abstract: In an absorption process in which an absorption medium is utilized to absorb H.sub.2 S from a feed gas containing H.sub.2 S, the flow rate of the lean absorption medium is manipulated so as to maintain the actual H.sub.2 S concentration in the product gas stream from the absorption process substantially equal to a desired value for the H.sub.2 S concentration. However, if the H.sub.2 S concentration in the rich absorption medium stream exceeds a high limit, the control of the lean absorption medium flow rate so as to maintain a desired H.sub.2 S concentration in the product gas stream is overridden until such time as the H.sub.2 S concentration in the rich absorption medium stream is below the high limit.

Abstract: A method of chemiluminescently determining a sulfide which is either hydrogen sulfide or methyl mercaptan by reacting the sulfide with chlorine dioxide at low pressure and under conditions which allow a longer reaction time in emission of a single photon for every two sulfide containing species, and thereafter, chemiluminescently detecting and determining the sulfide. The invention also relates not only to the detection method, but the novel chemical reaction that generates chemiluminescent light and a specifically designed chemiluminescence detection cell for the reaction.

Abstract: A system is disclosed for controlling the environment and temperature in the initial thermal reaction zone of an at least two-zone Claus thermal unit by means of control signals. Both a feed-back control and a feed-forward control are disclosed.

Abstract: A semiconductor gas sensor for use in equipment for detecting small amounts of H.sub.2 S. The method of sensor fabrication comprises spray deposition of a mixture of metal oxides mixed together with various metal and non-metal materials which serve in the finished product as activators, dopants, and/or film binder materials, and including in suspension a molecular sieve material, for enhancing and defining porosity on a scale of molecular dimensions in the finished sensor. All of the foregoing materials are suspended in a suitable solution and preferably sprayed onto a heated insulating substrate to form the finished product. The example sensor, capable of selective detection of H.sub.2 S in air and a sensitivity of less than 1 PPM (part per million), is comprised of a platinum activated alumina, tin oxide, and zeolite molecular sieve material.

Abstract: A gaseous stream of steam is analyzed for hydrogen sulfide by keeping the gas stream above its dew point while withdrawing a representative sample, mixing the sample with a gas having a dew point lower than that of the gaseous stream to form a mixture with a dew point below that of the gaseous stream, and analyzing the mixture at a temperature above its dew point for hydrogen sulfide.

Abstract: A method and apparatus for detecting hydrogen sulfide with improved longevity. The hydrogen sulfide detector includes a semiconductor comprised of indium oxide attached to an inert substrate. A noncontinuous film of an inert conductor such as gold is deposited on the semiconductor and means are provided for measuring a change in conductance of the semiconductor. In one embodiment tin oxide may be substituted for indium oxide. Also a method of detecting hydrogen sulfide including the steps of: coating a semiconductor with a noncontinuous film of an inert conductor, maintaining the temperature of the semiconductor in a range sufficient to insure proper response and recovery actions of the semiconductor when it is exposed to hydrogen sulfide; and exposing the coated semiconductor to a gas containing hydrogen sulfide while measuring the change in conductance in the semiconductor. The semiconductor may be made up of tin oxide or indium oxide and the inert semiconductor may be gold.

Abstract: A method and an apparatus for photometrically analyzing the hydrogen sulfide concentration in a stream containing at least a first predetermined concentration of bonded hydrogen sulfide-amines and ultraviolet radiation-absorbing impurities is characterized by isolating a first, reference, sample of the stream and removing the hydrogen sulfide from the reference sample until a second, lower, predetermined concentration remains. Thereafter, the first, reference, sample is photometrically analyzed and a reference signal representative of the ultraviolet radiation-absorbing characteristics of the first, reference, sample is produced. The reference signal is thereafter used in the photometric analysis of a second sample to produce a signal representative only of the hydrogen sulfide concentration in the second sample.

Abstract: An HCl monitor is provided for the extractive analysis of high-temperature, high-pressure, coal-derived process streams. The monitor is capable of HCl concentration measurement in the presence of all known coal gasification products, with detection being based on the ability of HCl to protonate a high boiling alcohol (solvent) and, thus, enhance the conductivity of the alcohol. Conductivity is then related to HCl concentration. The observed high degree of sensitivity that can be achieved is a result of analyte preconcentration prior to the conductivity measurement due to the fast dissolution rate of HCl into the alcohol solvent, coupled with a large analyte gas-to-solvent ratio.