METHOD OF PREPARING SORBENT Russian patent published in 1997 - IPC

FIELD: sorbents. SUBSTANCE: invention concerns sorbents for removing heavy and radioactive metal ions from drinking water. Hardwood is treated with solution containing 0.5-2.0 mol/l phosphoric acid and 2-6 mol/l urea at 60-90 C for 1-3 h at solids to liquid ratio 1:(5-20). Material is further pressed, dried, and thermally treated at 140-170 C for 1-3 h. Washed and finally dried sorbent has exchange capacity 3.1-4.6 mg-eq./g and coefficients of distribution of microamounts of plutonium, uranium, and americium within the range 5•10³-6•10⁴ cu.cm/g. EFFECT: increased capacity and selectivity in respect to transuranium elements. 3 cl, 1 tbl