Process Intensification on Synthesis of Nanoparticles in a Spinning Disc Reactor

Abstract

Process Intensification on Synthesis of Nanoparticles in a Spinning Disc ReactorThe spinning disc reactor with its characteristic fluid dynamics in a thin liquid film on a rotating surface is very potent in gaining access to nanoparticles. To identify the influencing parameters methodically, the micromixing efficiency is determined by the Villermaux-Dushman reaction, a system of competitive parallel reactions. The precipitation of barium sulfate with its fast reaction kinetics and short induction time is used to validate the results. These findings are subsequently applied on the size-selective synthesis of superparamagnetic magnetite nanoparticles via precipitation reaction. Particles size could be controlled in the range between 5 and 10 nm.

Influencing factors in the CO-precipitation process of superparamagnetic iron oxide nano particles: A model based study

“…An explanation for this effect might be provided by the nucleation pathways according to Lamer (1950) [49]. The solubility of the iron salts improves [66] while the pH decreases with increasing temperatures [67]. Thus, the relative supersaturation of the reaction medium is reduced [41].…”

Controlling nanomaterial synthesis, chemical reactions and self assembly in dynamic thin films

“…However this requires the use of ammonia (NH 3 ) gas at ambient pressure as a source of base over the dynamic aqueous thin film of Fe 2+/3+ precursors on the surface of the SDP, with the liquid delivered through a jet feed at room temperature. 47,48 The size of Fe 3 O 4 nanoparticles is controlled with a narrow size distribution over the range 5 nm to 10 nm, and the material has very high saturation magnetizations, in the range 68-78 emu g À1 , in accordance with super-paramagnetic behaviour. Here the size, size distribution and morphology of Fe 3 O 4 nanoparticles can be controlled by varying the operating parameters of the SDP, including concentrations, disc rotation speed, surface texture (grooved or smooth), and the use of NH 3 as the base.…”

“…The formation of barium sulfate particles in aqueous media at 25 1C has been established for a smooth 0.5 m diameter SDP. [48][49][50] At rotational speeds higher than 900 rpm, spontaneous precipitation occurs with crystals B0.7 mm in size. At a super-saturation ratio of 2000, the number of generated crystals is comparable with those generated using a T-mixer, but with much higher energy efficiency.…”

Visual Study of Liquid Flow in a Spinning Disk Reactor with a Hydrophobic Surface

“…Studies of liquid flow contribute to applications of SDRs in many chemical processes, such as catalyzed reactions (α-pinene oxidation , and photocatalytic degradation of methylene blue , ), polymerization (styrene polymerization, , condensation polymerization, and free-radical polymerization , ), preparation of polymers and nanoparticles, spray drying of molten slag and monodisperse solid aerosols, etc. Recently, SDRs have been widely applied in fast precipitation reactions. − However, for the precipitation reactions to produce the nanoparticles by a SDR, there are sometimes severe fouling problems . The fouling particles, on one hand, affect the liquid flow behavior in the reactors and then affect the heterogeneous nucleation processes; on the other hand, it is bad for a product’s quality within an impurity. , …”