发明名称 |
PROCESS FOR PREPARING CALCIUM SULPHATE |
摘要 |
PROCESS FOR PREPARING CALCIUM SULPHATE A simple process for preparing acicular calcium sulphate dihydrate is provided in which a slurry of calcium carbonate containing 100 to 800 grams per litre calcium carbonate is mixed with a solution of sulphuric acid containing 80 to 500 grams per litre sulphuric acid in proportions which produce a calcium sulphate slurry having a pH from 0.5 to 1.5. The process can be used to neutralise by-product sulphuric acid from the preparation of titanium dioxide with crushed limestone. Preferably the calcium sulphate slurry is stirred after formation to reduce the level of unreacted carbonate. The calcium sulphate produced has an aspect ratio of at least 4:1 and has excellent properties for use in paper. The process enables the production of acicular calcium sulphate without employing special crystallisation procedures.
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申请公布号 |
CA2099041(A1) |
申请公布日期 |
1994.01.02 |
申请号 |
CA19932099041 |
申请日期 |
1993.06.23 |
申请人 |
TIOXIDE GROUP SERVICES LIMITED |
发明人 |
NENCINI, PIERGIORGIO;BARONTI, RUTILIO |
分类号 |
C01F11/46;(IPC1-7):C01F11/46 |
主分类号 |
C01F11/46 |
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