Title: Journal of Geochemical Exploration

Title: Journal of Geochemical Exploration

ISO Abbreviated Title: J. Geochem. Explor.

JCR Abbreviated Title: J Geochem ExploR

ISSN: 0375-6742

Issues/Year: 8

Journal Country/Territory: Netherlands

Language: Multi-Language

Publisher: Elsevier Science BV

Publisher Address: PO Box 211, 1000 AE Amsterdam, Netherlands

Subject Categories:

Geochemistry & Geophysics: Impact Factor 0.486, 35/45 (2000)

Gaballah, I. and Kilbertus, G. (1998), Recovery of heavy metal ions through decontamination of synthetic solutions and industrial effluents using modified barks. Journal of Geochemical Exploration, 62 (1-3), 241-286.

Full Text: J\J Geo Exp62, 241.pdf

Abstract: Raw and chemically treated tree barks were used for the decontamination of synthetic solutions containing 10, 100 and 1000 ppm of arsenic, cadmium, copper, chromium, iron, lead, mercury, nickel and zinc. Industrial effluents were decontaminated on the laboratory and pilot scales. Metal removal from solutions depends on the pH, the initial concentration, the bark species and, to some extent, on the anion, It varies from 20 to 99% of the initial heavy metal ions ‘HMI’ content in the solution. The average retention capacity of the created bark varies from about 0.25 to 4.36 mmol/g of dry modified bark. Full extraction of HMI from the saturated modified bark was made possible with dilute acid allowing the regeneration of the bark for reuse as an ion exchanger. Bark loaded with heavy metals was analyzed by scanning electron microscopy ‘SEM’ and infrared ‘IR’ spectroscopy. Metal distribution was uniform in the bulk of the bark. No metal segregation was observed. It seems that HMI were chelated to the acidic (phenolic and/or carboxylic) sites of the bark. Anions were not detected into the loaded bark with either the SEM-EPMA or the CR spectroscopy, Incineration of the bark loaded with copper or chromium resulted in ashes containing up to 70% of metal oxides. Pyrolysis of the bark loaded with copper led to solids containing 10% of metallic copper and about 85% carboniferous matter. Such materials can be recycled for the production of secondary metal using the current industrial units. The suggested process can be used for the decontamination of industrial effluents or polishing of treated effluents by conventional technology. It was possible to decrease the effluents’ HMI content to ppb level. This : research can be considered as a demonstration of the possibility of using a waste, of low economic value, to resolve an environmental problem such as effluents’ decontamination. Moreover, the approach is to try to eliminate the pollution due to the HMI by their recycling instead of their disposal as waste. (C) 1998 Elsevier Science B.V. All rights reserved.

Keywords: Acid, Arsenic, Bark, Binding, Cadmium, Chromium, Copper, Decontamination, Extraction, Heavy Metal, Heavy Metal Ions, Heavy Metals, Heavy-Metal, Industrial Effluents, Iron, Lead, Mercury, Metal, Metal Ions, Metals, Nickel, pH, Pollution, Regeneration, Removal, Salts, Sem, Tannins, Uranium, Waste, Water, Wood, Zinc

Meima, J.A. and Comans, R.N.J. (1998), Reducing Sb-leaching from municipal solid waste incinerator bottom ash by addition of sorbent minerals. Journal of Geochemical Exploration, 62 (1-3), 299-304.

Full Text: J\J Geo Exp62, 299.pdf

Abstract: This paper investigates the mechanisms controlling Sb-leaching from fresh Municipal Solid Waste Incinerator (MSWI) bottom ash, as well as the possibilities of controlling the extent of Sb-leaching by the addition of sorbent minerals to the bottom ash. In alkaline MSWI bottom ash Sb is possibly incorporated in ettringite-like minerals. When weathering/carbonation continues the ettringite dissolves resulting in a mobilisation of Sb. A: neutral pH values the leaching of Sb is likely to be controlled by sorption to amorphous Fe/Al-(hydr)oxides. It has been shown that Sb can effectively be removed from solution if salts of Fe(III) or AI(III) are added to the bottom ash. This addition of Fe(III)/Al(III)-salts leads to (1) the in-situ precipitation of Fe/Al-hydroxides and sorption/coprecipitation of contaminants such as Sb, and (2) a lower bottom ash pH and thus an increased affinity of oxyanions for sorption to Fe/Al-(hydr)oxides. (C) 1998 Elsevier Science B.V. All rights reserved.

Keywords: Antimony, Bottom Ash, Immobilisation, Leaching, Mechanism, Sorption, Sediments, Antimony, Iron

Twardowska, I., Kyziol, J., Goldrath, T. and Avnimelech, Y. (1999), Adsorption of zinc onto peat from peatlands of Poland and Israel. Journal of Geochemical Exploration, 66 (1-2), 387-405.

Full Text: J\J Geo Exp66, 387.pdf

Abstract: Peat, defined as young Quaternary, mainly Holocene, organogenic sedimentary rock in the first stage of coalification, has received increasing attention due to its potential to act as an ubiquitous effective agent for the recovery of valuable metals, for the removal of metal ions from dumping site leachate and wastewater, or for retrospective monitoring of their migration and accumulation in the environment. For these purposes, adsorption capacity and binding strength of peat with respect to the metal ions under different conditions, as well as the mechanism of binding-release should be thoroughly known. To date, this knowledge is still limited. In this paper, results of studies on adsorption-desorption properties of Zn²⁺, which is one of the most mobile trace metals in the environment, in representative Polish and Israeli peat samples are presented. Batch studies were performed for Zn²⁺ in both single cation and a binary system (Zn-Cd) at pH 4.0. Column experiments under saturated flow conditions with Zn concentrations of 250 and 500 mgdm^-3 in the input solution at pH 4.0 (monometallic system) were also conducted. Finally, batch and column zinc adsorption experiments on selected peat samples were carried out using real multi-component wastes from the electroplating process. To assess the binding strength of peat with respect to zinc, sequential extraction by Tessier et al. (1979) modified by Kersten and Forstner (1988) was applied. The adsorption capacity for zinc of low-moor Polish peat, which is typical for the Northern Hemisphere with pH 5.02-6.54, was 15, 800 to 33, 700 mgZn kg^-1. Lower values were found for the Israeli peat. The presence of mass equivalent amounts of Cd showed only a moderate suppressing influence on the uptake of Zn by different peat matter. This suggests a weak competition of metal ions for adsorption sites available, despite binding of these metals in similar mass ratios in the same most labile fractions. There was, however, a difference in the binding of Zn and Cd in the more stable fractions, where no competition between Zn and Cd occurred. A significant difference in fractionation of Zn sorbed in batch vs, column experiments, was indicated. In particular, higher Zn enrichment in the ‘insoluble organic’ fraction under dynamic flow conditions was observed. Desorption experiments proved that zinc can be partially released with acid treatment from the labile fractions. (C) 1999 Elsevier Science B.V. All rights reserved.

Keywords: Extraction, Metals, Fe, Peat, Humic Materials, Zinc, Adsorption, Selective Extraction, Desorption