Effect of Citric Acid Modification of Aspen Wood on Sorption of Copper Ion

Authors:

Abstract
Milled aspen wood was thermochemically modified with citric acid for the purpose of improving the copper (Cu2+) ion sorption capacity of the wood when tested in 24-hour equilibrium batch tests. The wood-citric acid adducts provided additional carboxyl groups to those in the native wood and substantially increased Cu2+ ion uptake of the modified wood compared with that of the unmodified wood. Sorption capacity (qe) measured with an unbuffered standard solution increased to a maximum of 7.9 mg Cu2+ ion/g of wood (treated) from 1.3 mg Cu2+ ion/g wood (untreated). When measured with a buffered standard solution, the qe increased to a maximum of 13.8 mg Cu2+ ion/g of wood (treated) from 4.1 mg Cu2+ ion/g wood (untreated). The treatment necessary for maximum qe was 2 hours at 130°C. Modification treatments included three time periods (2, 4, 6 hours) and three temperature regimes (110, 120, 130°C). To further evaluate the efficacy of modification treatments, weight change after treatment was monitored a...

This publication has 16 references indexed in Scilit: