Comparison of sugarcane pressmud with traditional low-cost materials for adsorption of lead and zinc in mining areas

Author(s)

Raimondi, I. M. ; Vieira, E. M. ; Vaz, L. A. A. ; Rodrigues, V. G. S.

• Document type: Journal article
• Source: INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY; v. 19, n. 6, p. 18-pg., 2021-06-08.

Abstract

This paper aims to assess the potential of the composted sugarcane pressmud, as a reactive material for lead and zinc, comparing its adsorption, desorption, bioaccessibility, and cost/efficiency with more traditionally studied low-cost adsorbents for potentially toxic metals. For this, sugarcane pressmud, peat, zeolite clinoptilolite, and zeolite clinoptilolite enrichment with sodium were investigated. All materials were capable of removing lead and zinc in high concentrations, and the removals are dependent on the initial concentration. Both clinoptilolites were considered the most efficient for lead, followed by sugarcane pressmud. Regarding zinc, sugarcane pressmud had the highest performance, reaching around 72% of removal at 240 mg L-1. The pseudo-second-order kinetic model is satisfactorily suited to adsorption for all materials. Sugarcane pressmud attained the equilibrium faster than others (within 60 min), and it was considered the cheapest one (0.01 and 0.04 U$ for gram of lead and zinc removed). Langmuir described a monolayer sorption capacity (of 8.7738 mg g(-1)) of zinc onto sugarcane pressmud. In desorption and bioaccessibility assays, all the materials are capable of maintaining both potentially toxic metals at the binding sites, although most of the elements adsorbed in organic materials (sugarcane pressmud and peat) are in their bioaccessible form (above about 80%), requiring proper usage planning, and correctly handled. Thus, the results demonstrate that sugarcane pressmud (an abundant and inexpensive agro-waste material) may be a promising alternative as a reactive material for remediation in contaminated mining areas by lead and zinc. (AU)

• FAPESP's process: 14/07180-7 - Study of the soil contamination degree in the area of the former mining plant Plumbum (Adrianópolis, PR) due to the disposal of mining waste
• Grantee: Valéria Guimarães Silvestre Rodrigues
• Support Opportunities: Regular Research Grants