Abstract: An adsorptive separation process for separating ethylbenzene from a feed mixture comprising ethylbenzene and a plurality of xylene isomers which process comprises contacting the feed mixture with an adsorbent comprising strontium and potassium exchanged type X or type Y zeolite, selectively adsorbing substantially all of the said xylene isomers to the substantial exclusion of the ethylbenzene and thereafter recovering high-purity ethylbenzene. A desorption step may be used to desorb the adsorbed xylene isomers. The process can be either in the liquid or vapor phase.

Abstract: This invention relates to the removal from gaseous mixtures comprising hydrogen chloride or sulfuryl fluoride and hydrogen chloride of hydrogen fluoride impurity by solubilization of the latter with sulfur dioxide.

Abstract: Raw sewage may be presently treated by mixing screened raw sewage with activated carbon. The mixture is then allowed to stand in a first tank for a period required to settle the suspended matter to the bottom of the tank as a sludge. Thereafter, the remaining liquid is again mixed with activated carbon and the mixture is transferred to a secondary settling tank, where it is permitted to stand for a period required for the remaining floating material to settle as sludge and for adsorption of sewage carbon as well as other impurities to take place. The sludge from the bottom of both tanks is removed and pyrolyzed to form activated carbon and ash, which is mixed with the incoming raw sewage and also mixed with the liquid being transferred from the primary to the secondary settling tank. It has been found that the output obtained by the pyrolysis process contains an excess amount of ash.

Abstract: A wet gas cleaning system and process for removing particulates from a dirty process air stream including means for introducing the dirty process gas into a drying chamber and simultaneously therewith spraying or otherwise re-introducing the removed particulates or solids in finely divided form as a slurry into the chamber, collecting agglomerated particulates resulting from drying of the mixture or process gas and slurry in a separator while passing the resulting gas stream containing the remaining fine particulates into a high energy wet scrubber and simultaneously therewith introducing a recycled scrubber solution thereto and removing the remaining fine particulates from the scrubber in the form of a slurry.

Abstract: An arrangement for the degassing of metallic melts in which a rotating member is immersed in the melt. The rotating member has step-shaped elements which form vacuum chambers or spaces during rotation of the member. The vacuum spaces are not filled with melt, and gases are extracted from the melt and carried away from the vacuum spaces with the application of inert gases or reaction gases.

Abstract: Silver is recovered from photographic waste liquids containing emulsified silver, silver compounds, and gelatin by reacting therewith a proteolytic enzyme while the reactants are maintained in an alkaline condition. Then the reactants are acidified to a pH of 4.2 or less by introducing an acid such as HCl or H.sub.2 SO.sub.4. Precipitation of gelatin-bound silver and silver compounds occurs upon acidification, and the precipitate is allowed to settle out in a settling tank. Supernatant liquid is removed from the top, neutralized and sent to sewer. Settled sludge is removed from the bottom and silver recovered, as by incineration. The operation can be conducted either batch-wise or continuously.

Abstract: A plurality of selectively permeable membrane cells are mounted in parallel spaced-apart relationship to form a stack. Each cell includes a substrate and selectively permeable membranes positioned on the major surfaces thereof. The substrates are provided with flow ports at alternate end portions to provide a series flow path through the stack which is sealed by peripheral gasket members and end plates. The stack is adapted for use in pressure and vacuum gas enricher systems.

Abstract: A process for recovering a dissolved component in high concentration from liquid streams containing said component in low concentration comprising adsorbing said component on a bed of adsorbent, passing a solution containing a high concentration of said component through said bed to increase the amount of component absorbed on said bed and passing an eluant through the bed to regenerate the adsorbent and produce an eluate having a high concentration of said component.

Abstract: An improvement in closed cycle regeneration of sodium zeolite water softeners using sodium chloride soft brine input which comprises correlating the volume of liquid through the zeolite softener column so that in the effluent the alkaline earth metal content calculated as calcium carbonate has a maximum value of about 16,000 ppm. The sodium chloride soft brine input is selected as 8-12% with optimum 10%.

Abstract: A method for recovering chlorine from a chlorine-containing gaseous mixture containing carbon dioxide which comprises the steps of cooling said mixture in a rectification column of total-reflux type to prepare liquid chlorine, then subjecting the liquid chlorine to temperature control, whereby liquid chlorine of high purity is recovered in high yield.

Abstract: A tank containing a bed of particulate material, e.g. a sand filter bed or an ion exchange bed, has a bed-supporting bottom structure formed by upper and lower bottom plates rigidly connected with each other through a plurality of vertical sleeves opening into the spaces above and below the tank bottom structure. Openings in the wall of each sleeve connect the interior of the sleeve with the compartment formed between the bottom plates. A strainer unit is removably inserted in each sleeve through the lower end of the sleeve and passes liquid between the bed and the compartment between the bottom plates by way of the openings in the side wall of the sleeve. An adjustable valve member accessible from below the tank bottom structure serves to control the flow of liquid through the strainer unit.

Abstract: A method for treating waste gases containing radioactive contamination, particularly krypton and xenon nuclides. The waste gas stream to be decontaminated is initially conducted through an enrichment system wherein the waste gas stream is divided into at least two partial streams one of which is substantially free from the radioactive impurities and constitutes the poor gas fraction and another of which constitutes the rich gas fraction. The poor gas fraction is discharged, at least in part into the atmosphere while the rich gas fraction is fed into an activated carbon delay path whose output is discharged, either directly or indirectly into the atmosphere. Apparatus for carrying out the method is also disclosed.

Abstract: A gas adsorber cell for use in high efficiency gas cleaning systems and the like, and having provision for obtaining a representative and undisturbed sample of the adsorbent material to permit periodic testing of the efficacy of the adsorbent material. The adsorber cell comprises an enclosure including a pair of spaced perforated sheets adapted to receive an adsorbent material therebetween, a sample holder also adapted to be filled with the adsorbent material and having perforated opposite ends, and means for removably mounting the sample holder between the sheets such that a representative portion of the gas passing through the adsorber cell passes through the sample holder. The holder may then be removed to permit periodic testing of the adsorbent material carried therein.

Abstract: The sulfur trioxide, sulfuric acid vapor and sulfuric acid mist content of the effluent gas stream from a contact process sulfuric acid absorber are substantially decreased by pre-treating the gas stream prior to its passage through a conventional mist eliminator. The treatment steps include cooling the absorber effluent to below 100.degree.F and contacting same with aqueous sulfuric acid in a particular concentration range and thereafter maintaining the gas phase in the mist eliminator saturated with respect to H.sub.2 SO.sub.4 vapor.

Abstract: An improved vessel design is provided for contact of gas or vapour with particulate solid material, for example for adsorption systems such as air drying and solvent recovery systems, in which a plurality of trays for containing the particulate material are supported by a pillar structure within the shell of the vessel, the shell serving merely as an envelope which does not provide support for the trays thereby enabling a considerable reduction in material costs for the shell and greater design flexibility for the site where the vessel is to be installed. The pillar preferably forms a manifold for conveying gas or vapour streams to or from each of the trays and deflecting baffles for the gas or vapour streams are also provided. A sparge pipe may also extend along the duct to introduce steam or other purge gas for regeneration of an adsorbent in situ.

Abstract: The invention relates to a method of purifying sulphuric acid containing mercury in a plant for the production of sulphuric acid according to the contact process which involves drying moist roaster gases containing sulphur dioxide in at least two drying towers where the major part of the water content is absorbed in the first drying tower. The sulphuric acid containing mercury is in a quantity suitably measured to maintain the concentration between 70 and 80 percent by weight led to the first drying tower. To the second drying tower is led a sulphuric acid so that the concentration can be maintained between 95 and 103 percent by weight. The mercury is separated from a partial current from the circulating sulphuric acid in the first drying tower.

Abstract: An ion-exchanger material consisting of a cellulose ion-exchanger impregnated with .gamma.-manganese dioxide.A method for the treatment of waste water to remove dissolved high molecular organic compounds, ammonium and phosphate ions therefrom, comprising a pretreatment of said waste water with a chemical selected from the group consisting of precipitating agents and flocculating agents and subsequently passing the pretreated water through a bed consisting of a cellulose ion-exchanger impregnated with .gamma.-manganese dioxide.