Abstract: In order to explore and utilize the sea clays, the minerals of the sea clay samples were determined by using infrared spectrum instrument and Xray diffraction instrument. It shows that the content of the clay mineral in the sea clays is very high, in which I/S interlayer and illite are the dominant mineral composition. Minor of other minerals, including magnetite and hematite, are also present. Chemical composition analysis reveals that the content of Fe2O3 in the sample reaches about 7%. The East Pacific clay samples were bleached by introducing the reducing method of acid dissolving hydrogen. The effect factors on the iron removal and bleaching were discussed, such as acid kind and its concentration, medicament dosage, reaction time, calcinations temperature, and etc.The best bleaching scheme was established, through which the whiteness of the sea clay increases from 23.8% to 73.1%. Besides, the granularity, special surface area and dispersing ability of the samples before and after bleaching were tested, and it reveals that their activity has also been improved along with the increasing in whiteness.

Key words: sea clay, minerals composition, bleaching, acid dissolving hydrogen method