CROP RESIDUES AS ION-EXCHANGE MATERIALS - TREATMENT OF SOYBEAN HULL AND SUGAR-BEET FIBER (PULP) WITH EPICHLOROHYDRIN TO IMPROVE CATION-EXCHANGE CAPACITY AND PHYSICAL STABILITY
Ja. Laszlo et Fr. Dintzis, CROP RESIDUES AS ION-EXCHANGE MATERIALS - TREATMENT OF SOYBEAN HULL AND SUGAR-BEET FIBER (PULP) WITH EPICHLOROHYDRIN TO IMPROVE CATION-EXCHANGE CAPACITY AND PHYSICAL STABILITY, Journal of applied polymer science, 52(4), 1994, pp. 531-538
Ion exchange systems for the treatment of process water or wastewater
may benefit by the use of inexpensive, disposable exchange materials b
efore, or in place of, conventional regenerable exchange resins. Vario
us agricultural by-products have been proposed as suitable exchangers
for this role, but they generally fail to have adequate capacity and p
hysical stability for most applications. Two by-products, soybean hull
and sugar beet fiber, were found to have enhanced cation-exchange cap
acity and stability upon treatment with epichlorohydrin and base. Exch
ange capacity was determined by measuring calcium binding. Physical st
ability was judged by three different aqueous extraction regimens. The
most efficacious and economical reaction conditions found were: soybe
an hull and sugar beet fiber hydrated with water at a water-to-solids
ratio of 6.4 : 1 and 8 : 1 (v/w), respectively, and epichlorohydrin ap
plied at a 0.3 : 1 (v/w) ratio, for 6 h at room temperature. The resul
tant cross-linked materials had cation-exchange capacities of approxim
ately 0.9 (soybean hull) and 1.3 (sugar beet fiber) meq/g dry weight.
These epichlorohydrin-treated agricultural by-products may serve as co
st-effective, multivalent-cation exchangers. (C) 1994 John Wiley & Son
s, Inc.