What is a Spinning Disc Reactor ? Why is it important in Green Chemistry ?

Spinning Disc Reactor | Green Chemistry | Applications:  20171103-infinitysupercritical-spinning-disc-reactor-research

What is a Spinning Disc Reactor ? A SDR is a device which uses a spinning disc, typically in proximity of a stationary surface, to accelerate flow in a centrifugal manner. The components of which activates the flow (which is typically a liquid), to mix, agitate, shear, produce cavitation (vacuum), and produce temperature change, under the influence of boundary layer rotation. One of the main mechanisms at work here is called sonochemistry (producing ultrasonics by forming acoustical cavitation in liquids – which results in chemical activity). For example, when you cavitate water, you get a energy burst which includes UV light, heat, and sound. Also known as a shock wave.

Shock Waves and MicroJets:

A good example is cavitation in water. The spinning disc creates voids which collapse (and implode) that produces a shock wave. The resulting microjet produces thousands of psi of pressure.

https://arxiv.org/pdf/1706.03972.pdf

The SDR is unique, in that it provides a multifunctional platform, which allows the processor to control the flow acceleration by RPM, and flow temperature by adding or subtracting heat from the unit. Co-solvents, or other compounds can be added to the flow.

 

Configuration of a Spinning Disc Reactor

Rotors and stators can be rapidly reconfigured to stage pumping, mixing, shearing, extraction, and also provide a platform for complex chemical reactions, such as the production of Quantum Dots (QD). Take multiple chemical components within a liquid, best shows the incredible flexibility of the spinning disc reactor. While the reactions can be very complex, the mechanism to produce those reactions is very basic, and can be done under 4,000 RPM. Best of all, since reactions are very localized, the device is not considered a pressure vessel.

Micromixing Efficiency of a Spinning Disk Reactor

“The use of the spinning disk technology enables one to produce particles continuously

with controllable mean sizes down to 27 nm, without the risk of fouling or blocking.”

http://pubs.acs.org/doi/abs/10.1021/ie300411b

Ultra-wetting graphene-based PES ultrafiltration membrane – A novel approach for successful oil-water separation

“More importantly, the water permeability increased by 43 percent with greater than 99 percent selectivity. Based on our findings, we believe that the development of PES-G- PANCMI membrane will open up a solution for successful oil-water separation.”

https://www.researchgate. net/publication/305486217_Ultra- wetting_graphene- based_PES_ultrafiltration_membrane_- _A_novel_approach_for_successful_oil- water_separation

Higee technologies and their applications to green intensified processing

“…technologies which involve the application of high gravity fields, typically in the order of 100-1000g, in order to intensify dynamics, mixing and heat mass transfer in processing fluids.. such as spinning disc reactor (SDR) and rotating packed beds (RPB)… and rotor- stator SDR (RSSDR) … and rotating zig-zag bed (RZB) for achieving green processing benefits.”

https://www.researchgate. net/publication/308404045_Higee_technologi es_and_their_applications_to_green_intensifi ed_processing

A Taylor Vortex Photocatalytic Reactor for Water Purification

Flow evolution in a spinning disc reactor can result in very high overall efficiency of photocatalytic conversion. Centrifugal instability results in pollutant degradation.

http://pubs.acs.org/doi/abs/10.1021/ie001120i

Coal yields production of graphene quantum dots at Rice University

“The Rice lab of chemist James Tour found simple methods to reduce three kinds of coal into graphene quantum dots (GQDs), microscopic discs of atom-thick graphene oxide that could be used in medical imaging as well as sensing, electronic and photovoltaic applications. ”

From coal comes 20 percent yield graphene quantum dots. Non-toxic and fluoresce.

Evaluation of a Spinning Disc Reactor for Continuous Processing
“As part of an evaluation of equipment aimed at process intensification, use of a continuously operating spinning disc reactor (SDR) was investigated. Results obtained for two organic reactions and one crystallization are discussed. The SDR was found to be a useful tool for revealing intrinsically fast kinetics as well as for optimizing a process with such kinetics. Control of particle size distribution was demonstrated with the crystallization investigated.”

http://pubs.acs.org/doi/abs/10.1021/op0000834

Optimization of Biodiesel production in Spinning disc Reactor using Response Surface Methodology

“Spinning disc reactor have been fabricated and used for continuous alkali-catalyzed transesterification biodiesel production. The reactor was designed with a 110 mm diameter circular disc made of stainless steel as a static disc and another disc of same dimension made up of high density polyethylene to serve as rotating disc, enclosed on cylindrical vessel made of plexiglass.”

http://www.journalijar. com/article/5096/optimization-of-biodiesel- production-in-spinning-disc-reactor-using- response-surface-methodology/

CFD Numerical Simulation of Biodiesel Synthesis in a Spinning Disc Reactor

“In this paper a two-disc spinning disc reactor for intensified biodiesel synthesis is described and numerically simulated. The reactor consists of two flat discs, located coaxially and parallel to each other with a gap of 0.2 mm between the discs. The upper disc is located on a rotating shaft while the lower disc is stationary. The feed liquids, triglycerides (TG) and methanol are introduced coaxially along the centre line of rotating disc and stationary disc. .”

http://psjd.icm.edu.pl/psjd/element/bwmeta1. element.-psjd-doi-10_1515_cpe-2015-0002

The use of spinning disc reactor for processing ice cream base – effect of ageing in making model ice cream

“The results reveal that the SDR is capable of producing a highly stable ice cream base that requires significantly less ageing than the 18 h typically associated with the traditional process of making ice cream. The SDR process provides intense mixing of ingredients which facilitates the hydration of milk proteins and stabilizers.”

http://onlinelibrary.wiley. com/doi/10.1111/j.1365-2621.2009.01934. x/full

Spinning Disc Reactors -A novel processing machine for the food and chemical industry

“Ability to very rapidly heat and cool fluids, especially viscous fluids; pasteurization, fine crystal formation. Very low delta T gives less thermal damage. Self-cleaning easy clean characteristic, enhanced mass transfer for evaporation and odor removal with less thermal damage. Effective use of UV radiation (sunshine treated!) Unique combination of shear and draw gives opportunities for structure manipulation”

http://www.flandersfood. com/sites/default/files/ct_bestand/10/10/21/5 %20FFTD%20Henderson%20.pdf

Concentration of Apple Juice Using Spinning Disc Reactor Technology

“The SDR-made reconstituted apple juices are comparable to both the original pure- pressed apple juice sample and the commercial reconstituted product… It can be concluded that this novel SDR technology is capable of producing apple juice concentrates efficiently without compromising the quality of the juice products. ”

https://www.omicsonline.org/concentration-of- apple-juice-using-spinning-disc-reactor- technology-2157-7110.1000108.php? aid=1136

Shear Assisted Electrochemical Exfoliation of Graphite to Graphene

“Our findings on the crucial role of hydrodynamics in accentuating the exfoliation efficiency suggest a safer, greener, and more automated method for production of high quality graphene from graphite.”

http://pubs.acs.org/doi/abs/10.1021/acs.langmuir.5b04209?journalCode=langd5

Simple and Large-Scale Strategy to Prepare Flexible Graphene Tape Electrode

When the SDR is used to produce nanoparticles and graphite, the resulting powder can be used with various techniques to apply graphene to make printable electrodes. The technique is as simple as using acrylic transparent tape, and peeling away the tape from graphite foil.

http://pubs.acs.org/doi/abs/10.1021/acsami.6b14624

Green Reactors

“The advantages and disadvantages and the and design parameters that need to be considered when selecting microreactors to achieve process intensification (PI) are discussed. Oscillatory flow mixing (OFM) reactor, which includes oscillation of fluids using an external oscillator, is characterized by plug-flow RTD, high heat transfer, and short reaction times.  A plate-type reactor combines the high-heat- transfer capabilities of plate heat exchangers with the mixing of microreactors into a single unit, and is designed such that reactants can be injected at different locations along the flow path. The spinning tube-in-a-tube (STT) reactor is capable of creating sub- Kolmogoroff and near-Kolmogoroff eddies, which can reduce reaction time. The spinning disc reactor (SDR) has a very small reactor holdup, such that very hazardous reactions can also be carried out.”

https://www.researchgate. net/publication/282297425_Green_reactors

Summary

The spinning disc reactor (SDR) is an amazing device that has a small footprint with large mixing and chemical reaction potential. The primary benefits of using a SDR are the small size, complex mixing, shear, and sonochemistry reactions which can be performed in a non pressurized device. Using a liquid medium, such as water, can produce shock waves (and resulting microjets) which provide thousands of pounds of pressure within a very small space, to carry out reactions.

Leave a Reply