Room Temperature Synthesis of Magnetite (Fe3−δO4) Nanoparticles by a Simple Reverse Co-Precipitation Method

Upscale Design, Process Development, and Economic Analysis of Industrial Plants for Nanomagnetic Particle Production for Environmental and Biomedical Use

Very few economical and process engineering studies have been made concerning the scale-up and implementation of nanomagnetic particle manufacturing into a full-scale plant, and determination of its viability. In this work we describe such a study for two types of industrial plants, one for manufacturing magnetic particles for applications in the environmental area, and the other for manufacturing nanomagnetic particles for applications in the biotechnology area; the two different applications are compared. The following methodology was followed: establish the manufacturing process for each application; determine the market demand of the product (magnetic nanoparticles) for both applications; determine the production capacity of each plant; engineer all the manufacturing process, determining all the process units and performing all the mass and energy balances for both plants; scale-up the main equipment; and determine the global economic impact and profitability. At the end both plants are found to be technologically and economically viable, the characteristics of the final products being, however, quite different, as well as the process engineering, economic analysis, and scale-up.

A multiparametric model for the industrialization of co-precipitation synthesis of nano-commodities

Magnetite superparamagnetic nanoparticles (MNP) are becoming one of the firsts nanocommodity products. MNP find a number of applications and they are been produced at relatively large scale. The co-precipitation method presents many technical and economical advantages among alternative processes. However, the relationships between physical and chemical reaction conditions during the co-precipitation process and the resulting properties of obtained MNP are not yet fully understood. The novelty of this contribution is the establishment of the cross-dependency effects of the main physical and chemical parameters of the co-precipitation reaction on the properties of resulting MNP. The conditions were varied by following an experimental design. The crystallite size, particle size and magnetization of the MNP and the Z-potential and size of their aggregates were selected as main response properties. A set of equations in the form of 4D surface responses in the space of co-precipitation process variables was obtained and analyzed in terms of the resulting properties. The set of equations is useful to predict, optimize and tailor very precisely the properties of resulting MNP as a function of reaction conditions.

Green synthesis and optimization of nano-magnetite using Persicaria bistorta root extract and its application for rosewater distillation wastewater treatment

The aim of this research is to synthesize magnetite nanoparticles, using Persicaria bistorta root extract as the reducing agent, and to test its adsorption properties in the treatment of rosewater distillation wastewater. Taking advantage of Taguchi method, effect of synthesis parameters, including molar concentration of FeCl₂, concentration of plant extract, temperature, and pH on crystallite size and magnetization strength is studied. Based on the successful synthesis of magnetite nanoparticles and characterization experiments, Persicaria bistorta root extract can be considered as a proper alternative as the reducing agent. Data analysis shows that crystallite size and magnetization are positively correlated with concentration of FeCl₂ and pH, while inversely related to temperature and independent of plant extract concentration. The optimum values achieved for concentration of FeCl₂, temperature, and pH are 0.15 M, 70 °C, and 11, respectively, with the production of nanoparticles with magnetite size of 45.5 nm and magnetization value of 62.5 emu/g. In addition, the application of as-synthesized magnetite nanoparticles as an adsorbent for treatment of rosewater distillation wastewater proved its high adsorption capacity for chemical oxygen demand (COD) up to 149 mg/g. Adsorption data also shows a good fitness with Langmuir and Freundlich isotherm models.

Room Temperature Co-Precipitation Synthesis of Magnetite Nanoparticles in a Large pH Window with Different Bases

Magnetite nanoparticles (Fe₃O₄) represent the most promising materials in medical applications. To favor high-drug or enzyme loading on the nanoparticles, they are incorporated into mesoporous materials to form a hybrid support with the consequent reduction of magnetization saturation. The direct synthesis of mesoporous structures appears to be of interest. To this end, magnetite nanoparticles have been synthesized using a one pot co-precipitation reaction at room temperature in the presence of different bases, such as NaOH, KOH or (C₂H₅)₄NOH. Magnetite shows characteristics of superparamagnetism at room temperature and a saturation magnetization (Ms) value depending on both the crystal size and the degree of agglomeration of individual nanoparticles. Such agglomeration appears to be responsible for the formation of mesoporous structures, which are affected by the pH, the nature of alkali, the slow or fast addition of alkaline solution and the drying modality of synthesized powders.