Humic acid (HA ) was abstracted from leonardite,and a composite superabsorbent (HA PSA ) was prepared by compounding poly (acrylic acid ) and lignitic humic acid.

• 以风化褐煤为原料制备腐植酸(HA),将HA与普通型保水剂(PSA)复合,获得HA型保水剂(HA-PSA)。