| 摘要 |
A lignin product for dispersing cement and other finely divided mineral materials, such as clays and equivalent, and for plasticizing their water mixtures. The product is large-molecular such that at least 40 percent of the material consists of molecules whose molecular weight is higher than 10,000. The sulfonation degree of said lignin product is lower than 0.4. The product is obtained from a cellulose cooking to which have been added catalysts preventing the splitting and dissolution of carbohydrates, such as amines, quinone and/or antraquinone derivatives or equivalent, in order to stabilize the cellulose and the hemicellulose during the cooking. The lignin product has been isolated from the spent liquor by using ultrafiltration, and/or complementary ion exchange. |
