24.
    发明专利
    未知

    公开(公告)号:ES2137788T3

    公开(公告)日:1999-12-16

    申请号:ES98100504

    申请日:1998-01-14

    Applicant: DEGUSSA

    Abstract: Preparation of alkali or alkaline earth metal cyanide granules involves spraying an aqueous alkali metal hydroxide solution or an aqueous alkaline earth metal hydroxide suspension onto a fluidised product seed bed at 100-250 degrees C in a fluidised bed spray granulation reactor which is supplied with a hydrogen cyanide-containing gas in amount ≥ 1 mol HCN per metal equivalent, the introduced and formed water being evaporated by the fluidising gas supplied at 110-500 degrees C. Also claimed are sodium or potassium cyanide granules having a spherical particle shape with a smooth or raspberry-like surface structure, 0.1-20 mm particle diameter for 99 wt.% of the granules, ≥ 600 g/dm bulk density, less than 1 wt.% wear measured by the roller wear test (Erwaka TAR wear tester, 20 g sample, 60 minutes, 20 rpm.) and a clumping index of NOTGREATER 4 (measured by 14 day 10g load application onto a 100 g sample in a 5.5 cm inside diameter cylinder), the novelty being that the alkali metal carbonate content is less than 0.5 wt.% and the alkali metal formate content is less than 0.3 wt.%, the alkali metal in these by-products being the same as that in the cyanide. Preferably, the total alkali metal carbonate and alkali metal formate content is less than 0.4 wt.% and the granules are prepared by the above process using reaction gas from a BMA process and superheated steam as fluidising gas.

    26.
    发明专利
    未知

    公开(公告)号:DE59800022D1

    公开(公告)日:1999-09-30

    申请号:DE59800022

    申请日:1998-01-14

    Applicant: DEGUSSA

    Abstract: Preparation of alkali or alkaline earth metal cyanide granules involves spraying an aqueous alkali metal hydroxide solution or an aqueous alkaline earth metal hydroxide suspension onto a fluidised product seed bed at 100-250 degrees C in a fluidised bed spray granulation reactor which is supplied with a hydrogen cyanide-containing gas in amount ≥ 1 mol HCN per metal equivalent, the introduced and formed water being evaporated by the fluidising gas supplied at 110-500 degrees C. Also claimed are sodium or potassium cyanide granules having a spherical particle shape with a smooth or raspberry-like surface structure, 0.1-20 mm particle diameter for 99 wt.% of the granules, ≥ 600 g/dm bulk density, less than 1 wt.% wear measured by the roller wear test (Erwaka TAR wear tester, 20 g sample, 60 minutes, 20 rpm.) and a clumping index of NOTGREATER 4 (measured by 14 day 10g load application onto a 100 g sample in a 5.5 cm inside diameter cylinder), the novelty being that the alkali metal carbonate content is less than 0.5 wt.% and the alkali metal formate content is less than 0.3 wt.%, the alkali metal in these by-products being the same as that in the cyanide. Preferably, the total alkali metal carbonate and alkali metal formate content is less than 0.4 wt.% and the granules are prepared by the above process using reaction gas from a BMA process and superheated steam as fluidising gas.

    28.
    发明专利
    未知

    公开(公告)号:DE19750238A1

    公开(公告)日:1999-05-27

    申请号:DE19750238

    申请日:1997-11-13

    Applicant: DEGUSSA

    Abstract: A pressed article (I) is based upon pyrogenically produced silicon dioxide having a pore volume of 0.5-1.8 ml/g. Independent claims are included for: (i) the production of (I) by mixing pyrogenically produced silicon dioxide with methylhydroxyethylcellulose, wax and polyethylene glycol and water followed by extrusion, optionally cutting the extrudate to a desired length, drying at 70-150 degrees C and heating at 400-1200 degrees C for up to 10 hours; (ii) a supported catalyst (II) comprising (I) for the production of vinylacetate monomer, that contains palladium (Pd) and/or Pd compounds and alkali compounds; gold (Au) and/or Au compound (Pd/alkali/Au system) or cadmium (Cd) and/or Cd compounds (Pd/alkali/Cd system) or barium (Ba) and/or Ba compounds (Pd/alkali/Ba system) or Pd, alkali compounds and mixture of Au and/or Cd and/or Ba; and (iii) the production of the catalyst support (II) by soaking, spraying, condensing, dipping or precipitating the Pd, Au, Cd and/or Ba compounds onto (I), optionally reducing the metal, washing to remove the resulting chloride content, impregnating with alkali acetate or alkali compound that is converted under reaction conditions at least partially to alkali acetate.

    29.
    发明专利
    未知

    公开(公告)号:ID21246A

    公开(公告)日:1999-05-12

    申请号:ID981480

    申请日:1998-11-12

    Applicant: DEGUSSA

    Abstract: A pressed article (I) is based upon pyrogenically produced silicon dioxide having a pore volume of 0.5-1.8 ml/g. Independent claims are included for: (i) the production of (I) by mixing pyrogenically produced silicon dioxide with methylhydroxyethylcellulose, wax and polyethylene glycol and water followed by extrusion, optionally cutting the extrudate to a desired length, drying at 70-150 degrees C and heating at 400-1200 degrees C for up to 10 hours; (ii) a supported catalyst (II) comprising (I) for the production of vinylacetate monomer, that contains palladium (Pd) and/or Pd compounds and alkali compounds; gold (Au) and/or Au compound (Pd/alkali/Au system) or cadmium (Cd) and/or Cd compounds (Pd/alkali/Cd system) or barium (Ba) and/or Ba compounds (Pd/alkali/Ba system) or Pd, alkali compounds and mixture of Au and/or Cd and/or Ba; and (iii) the production of the catalyst support (II) by soaking, spraying, condensing, dipping or precipitating the Pd, Au, Cd and/or Ba compounds onto (I), optionally reducing the metal, washing to remove the resulting chloride content, impregnating with alkali acetate or alkali compound that is converted under reaction conditions at least partially to alkali acetate.

    Process for preparing alkali metal cyanide and alkaline earth metal cyanide granules and the high purity alkali metal cyanide granules obtainable thereby

    公开(公告)号:ZA98908B

    公开(公告)日:1998-08-04

    申请号:ZA98908

    申请日:1998-02-04

    Applicant: DEGUSSA

    Abstract: Preparation of alkali or alkaline earth metal cyanide granules involves spraying an aqueous alkali metal hydroxide solution or an aqueous alkaline earth metal hydroxide suspension onto a fluidised product seed bed at 100-250 degrees C in a fluidised bed spray granulation reactor which is supplied with a hydrogen cyanide-containing gas in amount ≥ 1 mol HCN per metal equivalent, the introduced and formed water being evaporated by the fluidising gas supplied at 110-500 degrees C. Also claimed are sodium or potassium cyanide granules having a spherical particle shape with a smooth or raspberry-like surface structure, 0.1-20 mm particle diameter for 99 wt.% of the granules, ≥ 600 g/dm bulk density, less than 1 wt.% wear measured by the roller wear test (Erwaka TAR wear tester, 20 g sample, 60 minutes, 20 rpm.) and a clumping index of NOTGREATER 4 (measured by 14 day 10g load application onto a 100 g sample in a 5.5 cm inside diameter cylinder), the novelty being that the alkali metal carbonate content is less than 0.5 wt.% and the alkali metal formate content is less than 0.3 wt.%, the alkali metal in these by-products being the same as that in the cyanide. Preferably, the total alkali metal carbonate and alkali metal formate content is less than 0.4 wt.% and the granules are prepared by the above process using reaction gas from a BMA process and superheated steam as fluidising gas.

Patent Agency Ranking