摘要:
Organic phosphines are produced by reacting an alkylene, cycloalkylene or aralkylene in the presence of a free radical-yielding catalyst. More specifically, a pressure reactor, which is provided in its interior with mixing elements, kept free from oxygen, and subdivided so as to comprise an upper cooling zone and a lower reaction zone, is continuously supplied from above with (a) a solution of the alkylene, cycloalkylene or aralkylene and the catalyst in an inert solvent, and (b) a stoichiometric excess of hydrogen phosphide, the said (a) and (b) reactants being supplied jointly with but separately from one another; the (a) and (b) reactants are mixed in the upper cooling zone of the reactor at about 0.degree. to 35.degree. C. and under a PH.sub.3 -pressure of about 80 to 300 bars; the resulting mixture, which travels downwardly in the reactor, is reacted in the lower reaction zone at about 90.degree. to 190.degree. C., the reactants being allowed to remain in the reactor for a period of time about 13 to 15 times longer than the half life period of the catalyst; the reaction mixture is removed through the bottom portion of the reactor and subjected to distillation so as to separate the organic phosphines.
摘要:
Methylphosphine oxides of the general formula (I) ##EQU1## are produced from hydroxymethylphosphines of the general formula (II) ##EQU2## in which formulae R and R' each stand for identical or different alkyl-, cycloalkyl-, aralkyl- or aryl groups having from 1 to 18 carbon atoms, or carrying substituents being inert under the reaction conditions.The methylphosphine oxides are more particularly produced by subjecting the hydroxymethylphosphines to a rearrangement reaction with the aid of radical-yielding compounds.
摘要:
Waste material consisting substantially of contaminated phosphorous acid is utilized. To this end, the phosphorous acid is introduced, with agitation into a liquid phase. Liquid phase and phosphorous acid are maintained in a ratio by volume between 1:1 and 10:1. The liquid phase is placed in a reactor, maintained between 250.degree. and 400.degree.C and selected from a phosphoric acid of the general formula H.sub.n.sub.+2 P.sub.n O.sub.3n.sub.+1, in which n substantially stands for a number between 1 and 5. Resulting hydrogen phosphide is removed. In the event of continuous operation, newly formed liquid phase is removed from the reactor, at the same rate as it is being formed.
摘要:
Production of 2-phenyl-ethylene phosphonic acid by reacting styrene with phosphorus pentachloride in a molar ratio of about 1 : 2 in liquid phase and hydrolyzing the resulting complex 2-phenyl-ethylene phosphonic acid tetrachloride with water. The reaction is more particularly started with the use as the liquid phase of the equimolar mixture of 2-phenyl-ethylene phosphonic acid dichloride and phosphorus oxychloride obtained as an intermediary product; styrene and phosphorus pentachloride are introduced thereinto with continuous agitation; resulting complex 2-phenyl-ethylene phosphonic acid tetrachloride is partially hydrolyzed by adding a predetermined quantity of water to an equimolar mixture of 2-phenyl-ethylene phosphonic acid dichloride and phosphorus oxychloride; a portion of the resulting clear solution is continuously used as the liquid phase and phosphorus oxychloride is continuously distilled off under reduced pressure from the balance portion of the solution; remaining 2-phenyl-ethylene phosphonic acid dichloride is hydrolyzed by continuous addition of overstoichiometric proportions of water to an aqueous solution of 2-phenyl-ethylene phosphonic acid; the aqueous solution is cooled and crystalline phosphonic acid is precipitated therefrom.
摘要:
The disclosure relates to a process for making a particulate agent stable to hydrolysis based on free-flowing, pulverulent ammonium polyphosphate by treating the ammonium polyphosphate with a thermosetting, artificial resin being water-insoluble when cured. More specifically, the disclosure provides for the ammonium polyphosphate, an aliphatic alcohol as a diluent, and a melamine/formaldehyde-resin or phenol/formaldehyde-resin to be placed in an autoclave and intimately mixed at room temperature; for the mixture to be heated to a temperature of about 80.degree. to about 180.degree. C. and allowed to remain over a period of 15 to 240 minutes at that temperature and under the pressure corresponding to the vapor pressure of the diluent; for the diluent to be separated and for the product so obtained to be dried.
摘要:
The invention relates to improving the degree of graphitization of carbon black produced by subjecting hydrocarbons which are liquid or gaseous under normal conditions to a thermal conversion reaction in the presence of oxygen or an oxygen-containing gas and steam, if desired, at temperatures of 1200.degree. to 2000.degree. C. and pressures of 1 to 80 bars. To this end, the carbon black is conveyed downwardly in a quasi-fluid state, within 1 to 5 hours through a sojourn zone in upright position, the sojourn zone being maintained at a temperature of at least 1200.degree. C.The invention relates to an apparatus for carrying out this process, the apparatus comprising a graphite tube; a steel container concentrically surrounding the graphite tube; a feed pipe penetrating into the interior of the graphite tube; a water-cooled discharge means; and a nitrogen feed inlet arranged below the lower end of the graphite tube; the space left between the graphite tube and steel container being occupied by insulating material.
摘要:
The disclosure relates to a process for removing organic compounds from wet-processed phosphoric acid with the aid of an adsorbant. To this end the disclosure provides for the acid to be heated to at least 250.degree. C. prior to treating it with the adsorbant. The disclosure also relates to an apparatus for carrying out the process.
摘要:
The disclosure relates to a process for making titanium dioxide concentrates from material containing titanium oxide and iron oxides. More particularly, the titanium oxide-containing material is calcined at temperatures of 870.degree. to 1300.degree. C., and then treated with a chlorine-containing gas at temperatures of 800.degree. to 1300.degree. C., if desired with addition of carbon.
摘要:
The disclosure relates to a process for after-treating extraction residues, termed raffinates, originating from the extractive decontamination of crude phosphoric acid. To this end, the disclosure provides for the raffinates to be converted to two separate solid matter fractions of differant chemical composition by admixing the raffinates with a calcium compound so as to establish a pH-value of 1.2 up to 2.5. Next, the resulting precipitate consisting essentially of gypsum is filtered off as a first solid matter fraction, and washed with water. The resulting filtrate and the wash water are made into a mixture and predetermined proportions of calcium compound are added so as to obtain, after complete reaction, a fully reacted filter cake with a pH-value of 9 up to 12, the resulting suspension being filtered off at a pH-value of 6 to 8. The filter cake consisting essentially of calcium phosphate is separated as the second solid matter fraction, and allowed to react completely.
摘要:
The present invention relates to a process for the oxidation of alkali metal phosphites to alkali metal phosphates at temperatures of between 400.degree. and 500.degree. C. To this end, alkali metal phosphites are employed in the form of an aqueous solution or suspension and, if necessary, the alkali metal : P atomic ratio in this feed material is adjusted to a ratio which at least corresponds to the atomic ratio desired for the final product.More particularly, the solution or suspension is spray-dried in a tower, in a single operational stage, by spraying in a flame zone. Starting material free from alkali metal phosphate and with an alkali metal : P atomic ratio equal to or greater than 3.5 is used for making a trialkali metal phosphate which is obtained in admixture with an alkali metal hydroxide. Starting material which contains from 25 to 45% by weight of alkali metal phosphate, calculated as phosphorus, based on their total phosphorus content, is employed for making alkali metal polyphosphates.