Abstract: A catalyst comprising a phosphorus-vanadium mixed oxide and existing in the form of geometric shapes, such as tablets, provides minimum expansion of the geometric shapes under process reaction conditions, since the catalyst in the form of said geometric shapes has been heated in an inert atmosphere at a temperature within the range of about 343.degree. C. (650.degree. F.) to about 704.degree. C. (1,300.degree. F.) prior to being exposed to an oxygen-containing atmosphere at an elevated temperature. This catalyst is suitable for the oxidation of a hydrocarbon, such as benzene or n-butane, to maleic anhydride.

Abstract: Optical density of terephthalic acid is reduced in excess of ninety percent by the direct addition of water to selected crystallizers in a precipitative process based on hydrogenation and flask crystallization.

Abstract: A method is disclosed for preparing overbased petroleum oxidates which comprises carbonating a petroleum oxidate in the presence of a base selected from the group consisting of alkali metal compounds and alkaline earth metal components. The petroleum oxidate is made by oxidizing petroleum oil in the presence of a base. The overbased petroleum oxidates are useful as rust inhibitors, dispersants, detergents, friction modifiers and as a substrate for overbased sulfonates, phenates, and salicylates. The overbased sulfonates, phenates and salicylates are easily overbased and have improved storage stability and improved rust inhibition.

Abstract: A method for purifying a dimethyl naphthalene dicarboxylate produced from a naphthalene dicarboxylic acid which is in turn produced by the liquid phase oxidation of a dialkylnaphthalene or partially oxidized derivative thereof in the presence of a catalyst comprising a bromine-containing component and at least one of a cobalt- or manganese-containing component.

Abstract: The present invention provides an apparatus and method for fluorescence detection. An ellipsoidal cylinder having a first focal line, a second focal line and an internal reflective surface is provided. An excitation source is disposed on the first focal line and a sample container is disposed on the second focal line. Filter means are disposed between the excitation source and the sample container. Both fluorescence detector and reference detector means are provided to detect, respectively, the fluorescence radiation and excitation radiation. Comparator means compare the signal from the fluorescence and reference detectors to determine the presence and concentration of fluorescent material within the sample container.

Abstract: The present invention relates to a process for producing aromatic compounds from a hydrocarbon gas containing paraffinic hydrocarbons under conversion conditions in the presence of a catalyst comprising a gallosilicate molecular sieve and a platinum metal component.

Abstract: An effective, efficient and safe method is provided to accurately determine the amount of catalyst in an ebullated bed reactor without depressurizing the reactor or exposing the hydrocarbon in the reactors to oxidizing, flammable, or explosive conditions. Measurements are made automatically by density detectors and pressure sensors along with other equipment.