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Transport parameters of selected neonicotinoids in different aquifer materials using batch sorption tests

Pietrzak Damian, Kania Jarosław, Kmiecik Ewa

Geology, Geophysics and Environment

2022

Vol. 48, no. 4

367--379

Contamination of surface and groundwater by neonicotinoids is a global problem and requires comprehensive action by individual countries in order to identify in detail the processes affecting the transport of these pesticides, their properties, and their harmfulness to the environment. The aim of this study was to assess the transport (expressed by sorption parameters) of selected neonicotinoids in the aquatic environment, using batch tests. Tests were carried out for acetamiprid individually and a mixture of five neonicotinoids (acetamiprid, clothianidin, imidacloprid, thiacloprid, and thiamethoxam), for three different aquifer materials and quartz sand. Based on the obtained values of the sorption parameters, the greatest sorption of neonicotinoids was observed on soil with the highest content of organic matter and clay minerals content, while no sorption of these pesticides was observed on quartz sand. In addition, it was noticed that individual neonicotinoids undergo sorption to a different degree — thiacloprid was the most sorbed (R-value in the range 3.13–26.03), while thiamethoxam was the least (R-value in the range 1.89–8.41).

The removal of Cr(VI) from the aqueous solution by granular ferric hydroxide (GFH) [commun.]

Yuan B, Bartkiewicz B.

Archives of Environmental Protection

2009

Vol. 35, no. 2

115-123

In this work, sorplion of chromium on granular ferric hydroxide (GFH) has been investigated using batch and column techniques. The adsorption behavior of Cr on GFH, depending on pH, contact time and sot-bent amount were studied. The equilibrium adsorption capacity of GFH for Cr was measured and extrapolated using Freundlich isotherms. Metal ions bounded to the GFH could be recovered by alkaline solution, and the GFH can be recycled. The sorplion capacity of GFH was 25.0 mg/g. The ion exchange of chromium on GFH follows pseudo-lirst-order kinetics. The intraparticle diffusion of chromium on GFH presents the limiting rate. The results indicated practical value of this method lor industry and also provide strong evidence to support the proposed thesis about the adsorption mechanism.

W pracy przebadano efektywność sorpcji chromu(Vl) na granulowanym wodorotlenku żelaza (GFH) w warunkach objętościowych i przepływowych. Badano skuteczność sorpcji zależnie od pH, czasu kontaktu i dawki adsorbentu. Pojemność sorpcyjną GFH zmierzoną w badaniach ekstrapolowano wykorzystując równanie izotermy Freundlieha. Pojemność ta wynosiła 25 mg/g. Jony metali zaadsorbowane na GFH mogą być z niego wymyte roztworem alkalicznym, co umożliwiałoby recyrkulację adsorbentu. Kinetyka wymiany jonów chromu na GFH może być opisana równaniem pierwszego rzędu. Kryterium limitującym wymianę jest dyfuzja międzycząsteczkowa. Wyniki wykazały praktyczną przydatność tej metody w przemyśle i stanowiły dowód na poparcie tezy wyjaśniającej mechanizm adsorpcji.