Synthesis of Colloidal Silver Using Lignosulfonates
Journal Title: Lesnoy Zhurnal (Russian Forestry Journal) - Year 2021, Vol 11, Issue 6
Abstract
Colloidal silver solutions can be used as catalysts for carrying out various chemical transformations of organic substances and solving the problems of disposal of toxic compounds, as well as antibacterial agents for combating pathogenic microflora, in the manufacture of lubricants and light-absorbing materials, coatings, sensors, conductive pastes, and high-performance electrode materials. The research purpose is to study the synthesis of colloidal silver using a solution of technical lignosulfonates (LST) as a stabilizer. Colloidal silver was synthesized as a result of the reduction-oxidation (redox) reaction of Ag(I) cations with glucose at 100 °C in the presence of lignosulfonates. The reaction was carried out in an alkaline medium, which is provided by the addition of ammonia water. Electronic spectroscopy was used to control the synthesis of colloidal silver. After the reaction, the solution turned dark brown and an intense absorption band with a maximum at 400 nm appeared on the electron spectra. The effects of reagent consumption and synthesis duration were studied. It was found that the optimal reagent consumption in the colloidal silver synthesis is as follows: 2.5–5 g glucose / g Ag, 0.3–1 g LST / g Ag, and 3–5 g NH3 / g Ag. The synthesis duration is 2–5 min. The resulting colloidal silver solution is stable for several months. Partial stratification without precipitation is observed during the solution storage. It is shown experimentally that the stratification is followed by a redistribution of colloidal silver particles. Electron spectroscopy confirmed the absence of colloidal silver particles in the upper layer. The reaction kinetics has been studied in experiments carried out under thermostatically controlled conditions at temperatures from 50 to 100 °C. The kinetic dependence is described by a first-order equation at the initial stage of the reaction, the duration of which depends on the temperature. The duration of the active part of the kinetic curves is 15–90 % of the total reaction time. The logarithm of the rate constant on the active section was proved to depend linearly on the reverse thermodynamic temperature (pair correlation coefficient is 0.9887). The activation energy was 47 kJ/mol. For citation: Plakhin V.A., Khabarov Yu.G., Veshnyakov V.A. Synthesis of Colloidal Silver Using Lignosulfonates. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 6, pp. 184–195. DOI: 10.37482/0536-1036-2021-6-184-195
Authors and Affiliations
V. A. Plakhin, Yu. G. Khabarov, V. A. Veshnyakov
Needle-Like Leaf Organs of Conifers. Part I. Modeling the Needle Cross-Section Perimeter
Despite the availability of measuring systems for estimating the surface area of leaf organs of higher plants, the need for simple standard methods for determining this indicator area remains relevant for plant physiolog...
Forest Sustainability of Ecotopes of the Volga-Akhtuba Floodplain when Cultivating Pine Plantations
In the south of European Russia, the largest sand massifs are found in the zone of dry steppes and semi-deserts. Effective utilization of such lands requires creation of protective forest planting of drought-resistant co...
Pan-European Approaches to the Classification of Habitats, Vegetation and Forest Types
The article describes the approaches and features of classification of forests, habitats and vegetation at the Pan-European level on the example of the classification of European forest types (EFT), the EUNIS habitat cla...
Analysis of Wind Load Effect on Greenhouse Frame for Cultivation Seedlings with Closed Root System
Reforestation is one of the priorities of the state policy of the Russian Federation. Artificial recreation of forests, including a closed root system seedling cultivation technology, has shown its high efficiency in the...
Influence of Climatic Factors on Scots Pine (Pinus sylvestris L.) Growth on the Coast of the Kandalaksha Bay of the White Sea
The purpose of this study is a comparative analysis of linear and radial increments of Scots pine (Pinus sylvestris L.) as a response to the growing conditions on the coast of the Kandalaksha Bay of the White Sea, as wel...