Inverse phase suspension polymerization of acrylamide in a batch oscillatory baffled reactor

Abstract

ABSTRACT:We report, for the first time, our experimental investigation of inverse phase suspension polymerization of acrylamide in a batch oscillatory baffled reactor. In such a reactor, the oscillatory motion is achieved by moving a set of orifice baffles up and down the column at the top of the reactor. The effects of both operational and design parameters on the mean particle size and size distribution of polymer beads were investigated, including oscillation amplitude, oscillation frequency, baffle spacing, baffle free area, and monomer addition time. The experimental results indicated that the mean particle size and size distribution of the polymer beads depended predominantly on the product of oscillation frequency and amplitude, i.e., the oscillation velocity. The size distributions are narrow and of essentially a Gaussian distribution. The level of fines produced is consistently less than 1% for all 100 experiments performed. We demonstrated that the mean particle size and size distribution in an oscillatory baffled reactor can be controlled precisely by simply selecting the appropriate oscillation velocity. The effect of the baffle spacing on the mean particle size is much less compared with that of the baffle free area. The monomer injection time has a noticeable influence on the mean particle size, but the rate of change is relatively small.

Evaluation of axial dispersion and mixing performance in oscillatory baffled reactors using CFD

“…The understanding and realization of the science in oscillatory baffled reactors (OBR) has promoted technological applications at both laboratory and industrial scales . The concept itself also fits well into the area of process intensification, as the improved mixing brings about significant enhancement in mass and heat transfer rates, as well as particle suspension/transportation and crystallization .…”

Population balance modelling of droplet coalescence and break-up in an oscillatory baffled reactor

“…The key feature of OBR is that mixing can be controlled to a very high degree of precision by ÿne tuning the oscillation conditions (oscillation amplitude and oscillation frequency), giving a wide range of mixing conditions, from "soft" mixing, exhibiting plug ow characteristics, to the most intense, approaching mixed ow conditions. As a result, OBRs are being increasingly exploited in Chemical Engineering unit operations in the pursuit of process enhancements (Mackley et al, 1990;Ni and Mackley, 1993;Hewgill et al, 1993;Ni et al, 1995Ni et al, , 1999Ni et al, , 2000Ni et al, , 2001Wilson et al, 2001). The droplet data used in this work were obtained in a study of suspension polymerisation of methylmethacrylate in a batch OBR of 50 mm in diameter, and the schematic diagram of the batch OBR is shown in Fig.…”

Valorization of waste cooking oil based biodiesel for biolubricant production in a vertical pulsed column: Energy efficient process approach

“…The vertical pulsed column (VPC) is a type of oscillatory baffled reactors (OBR) which is one means for the intensification of multiphase reactions. OBR applications have increasingly been investigated in a number of different chemical processes such as polymerization [16], crystallization [17,18], biodiesel synthesis [19,20] and ozonation reaction [21,22].…”