Waste tire rubber as heavy metal ion adsorbent

Abstract

Abstract The objective of this work was to develop waste tire rubber (WTR) as a heavy metal ion (Cu(II)) adsorbent. Effects of heat and acid treatment on efficiency of Cu(II) removal were examined from h-WTR, a-WTR, h/a-WTR and a/h-WTR with 40 mesh size. Results from UV-Vis spectrometer revealed that, at 0.5g/50ml adsorbent dosage, h-WTR had higher %removal of Cu(II) than other treated-WTRs. This may result from the highest surface area (51.61 m2/g) and pore volume (0.24 cm3/g) of h-WTR. The pores were possibly formed by the departure of small compounds generated from the rubber degradation. On the other hand, acid treated adsorbent present low efficiency, positive charges of the residual acid occupied on adsorbent surfaces played an important role on the Cu(II) adsorption capacity of a-WTR, h/a-WTR. SEM image presented the number of pores on surface of h-WTR. Results from h-WTR with different size revealed that the smaller size of WTR provided the higher %removal of Cu(II). This was possibly due to the higher efficiency of surface activation. Increasing an amount of adsorbent dosage from 0.5 to 5g/50ml slightly enhanced the %removal. In this study, WTR with > 90% Cu(II) removal was achieved when heat treatment was applied on 40 mesh WTR and 0.5g/50ml adsorbent dosage.