GB1486966A - Process for preparing calcium sulphate alpha-hemihydrate - Google Patents

Process for preparing calcium sulphate alpha-hemihydrate

Info

Publication number
GB1486966A
GB1486966A GB2069975A GB2069975A GB1486966A GB 1486966 A GB1486966 A GB 1486966A GB 2069975 A GB2069975 A GB 2069975A GB 2069975 A GB2069975 A GB 2069975A GB 1486966 A GB1486966 A GB 1486966A
Authority
GB
United Kingdom
Prior art keywords
hemihydrate
calcium sulphate
hours
sulphate alpha
preparing calcium
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB2069975A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Heavy Industries Ltd
Original Assignee
Mitsubishi Heavy Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Heavy Industries Ltd filed Critical Mitsubishi Heavy Industries Ltd
Publication of GB1486966A publication Critical patent/GB1486966A/en
Expired legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F11/00—Compounds of calcium, strontium, or barium
    • C01F11/46—Sulfates
    • C01F11/466—Conversion of one form of calcium sulfate to another
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B11/00—Calcium sulfate cements
    • C04B11/02—Methods and apparatus for dehydrating gypsum
    • C04B11/024—Ingredients added before, or during, the calcining process, e.g. calcination modifiers

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Inorganic Chemistry (AREA)
  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)

Abstract

1486966 Calcium sulphate alpha-hemihydrate MITSUBISHI JUKOGYO KK 15 May 1975 [15 May 1974] 20699/75 Heading ClA Calcium sulphate alpha-hemihydrate is produced from gypsum in a continuous process in which a CaSO 4 .2H 2 O slurry is heat treated with water under pressure in the presence of no more than 0À1% by weight of sodium citrate, based on the total weight of the gypsum, at a temperature of not lower than 140‹ C. wherein the average retention time of the slurry in the process is more than 0À5 hours but not more than 2 hours and preferably from 1 to 1À5 hours. Comparative examples of a batch process both with and without sodium citrate are given in addition to an example of the process described above.
GB2069975A 1974-05-15 1975-05-15 Process for preparing calcium sulphate alpha-hemihydrate Expired GB1486966A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP49053187A JPS593406B2 (en) 1974-05-15 1974-05-15 Alpha-Gatahansuisetsukou

Publications (1)

Publication Number Publication Date
GB1486966A true GB1486966A (en) 1977-09-28

Family

ID=12935858

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2069975A Expired GB1486966A (en) 1974-05-15 1975-05-15 Process for preparing calcium sulphate alpha-hemihydrate

Country Status (5)

Country Link
JP (1) JPS593406B2 (en)
DE (1) DE2522005A1 (en)
FR (1) FR2271185B1 (en)
GB (1) GB1486966A (en)
SU (1) SU791217A3 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107746195A (en) * 2017-02-06 2018-03-02 宁夏博得石膏科技有限公司 A kind of method of efficiently production alpha semi-hydrated gypsum

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2011363B (en) * 1977-12-29 1982-07-14 Idemitsu Kosan Co Production of calcium sulphate

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4838298A (en) * 1971-09-15 1973-06-05

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107746195A (en) * 2017-02-06 2018-03-02 宁夏博得石膏科技有限公司 A kind of method of efficiently production alpha semi-hydrated gypsum

Also Published As

Publication number Publication date
FR2271185B1 (en) 1980-11-14
JPS50145393A (en) 1975-11-21
FR2271185A1 (en) 1975-12-12
SU791217A3 (en) 1980-12-23
DE2522005A1 (en) 1976-04-08
JPS593406B2 (en) 1984-01-24

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Legal Events

Date Code Title Description
PS Patent sealed
746 Register noted 'licences of right' (sect. 46/1977)
PCNP Patent ceased through non-payment of renewal fee

Effective date: 19940515