Removal of platinum group metals from dilute process streams: Identification of influential factors using DOE approach

Purification of a dilute platinum group metals process stream using waste yeast biomass immobilized on plaster of Paris

“…The results from the control experiments showed that the adsorption of the species of interest was due to the functional groups on the biomass, as reported by Oke, Ndlovu, and Sibanda, (2014), and not affected in any way by the POP.…”

“…The technical viability and biosorption capacity of the Saccharomyces cerevisiae waste biomass for the removal of PGMs from synthetic solution in a batch system has been investigated previously (Oke, Ndlovu, and Sibanda, 2014). However, for practical and large-scale operation, a packed column is preferred since a batch system is usually limited to the treatment of small quantities of wastewater.…”

“…Glass beads were introduced at the top and the bottom of the packed column to prevent the adsorbent from floating. The dilute PGM process solution was conditioned to pH 3 (the optimum pH for adsorption obtained in the batch experiments (Oke, Ndlovu, and Sibanda, 2014) using 0.1 M NaOH and HCl solutions. The solution, with known concentration of solutes, was pumped through the column in an upflow direction using a peristaltic pump (Watson Marlow 5045) with variable speed adjustment.…”

“…The flow rates and bed depths were chosen based on information from the literature (Calero et al, 2009;Danny, Porter, and McKay, 2000). The pH and the time used were based on the information gathered from the batch studies (Oke, Ndlovu, and Sibanda, 2014).…”

“…The species of interest include sulphates, chlorides, Na, Ni, Se, Ru, Pd, Pt, and Ir. For the test work, the dilute process stream was conditioned to pH 3 (the optimum pH for PGM adsorption in the batch studies (Oke, Ndlovu, and Sibanda, 2014).…”