This work investigates the adsorption behavior of Diethylaminoethyl-cellulose-thiourea-glutaraldehyde (DEAE-C/TU/GA) sorbent, which was synthesized through the reaction of crosslinking of glutaraldehyde using thiourea for platinum (Pt(IV)) and palladium (Pd(II)) ions from leaching solutions. The effects of pH and adsorption parameters, such as the sorbent dosage, contact time, temperature, and adsorption isotherms, were studied. Furthermore, chemical adsorption kinetic studies for adsorptions of these metal ions were carried out. The adsorption equilibrium data were fit better using the Langmuir model than the Freundlich model. The activation energies (Ea) of Pt(IV) and Pd(II) were 77.70 and 23.03 kJ/mol, respectively. The best desorption reagent was 1.0 M HCl–1.0 M TU solution for both Pd(II) and Pt(IV), which could remove more than 85% of the Pt(IV) and Pd(II) in the fourth adsorption–desorption cycle.
The aim of this study is to investigate the utilization possibilities of steel slags, basic oxygen furnace (BOF) and electric arc furnace (EAF) slags, as backfill material in coastal structures. Within the scope of the study, physical, mechanical and chemical properties of the steel slags were investigated and their potential to create environmental risks were evaluated. The results showed that soundness loss and filler content ratio were below the limit values for steel slags to be used as backfill material. It was determined that the density, porosity, water absorption and Los Angeles abrasion ratios of steel slags were generally higher than natural aggregates. In order to reach the California Bearing Ratio (CBR) limit (> 25%), the maximum particle size of the steel slag was reduced to 25 mm. In this particle size, CBR of the slag samples generally gave better results compared to the natural aggregate (38%), except for Kardemir and Asil samples. In addition, the concentration values of heavy metals (Cu, Cd, Cr, Pb, Ni, Zn, Hg and As) were below the limit values specified in the regulation. It is suggested that EAF slags should be aged for at least 6 months and BOF slags for at least 24 months in open air conditions before being used as backfill material in coastal structures after the maximum particle size is reduced to 25 mm.
An approximate amount of 2 million tons of copper slag has been lying on the northern part of Turkey from ancient time. This slag contains 0.43% cobalt and 1% copper. This paper reports work carried out to process this slag for recovery of cobalt and copper.