http://www.leeds.ac.uk/speme/ipse/ding/ y.ding@leeds.ac.uk Process Intensification Using Particles Across Length Scales Professor Yulong Ding Institute of Particle Science & Engineering & Chemical Engineering Discipline University of Leeds, Leeds LS2 9JT, United Kingdom http://www.leeds.ac.uk/speme/ipse/ding/ y.ding@leeds.ac.uk

Process Intensification What is process intensification? Concept put forward in 1970s when ICI invented the HiGee process (a rapid spinning disc…) Such a concept has been used widely and some are long before 1970s! Heat transfer using extended surfaces Heat and mass transfer using internals Separation enhanced reaction processes Various intensive shear mixing processes Microfluidics & nanofluidics High throughput screening (Morden chemical & pharmaceutical practices) Intensive farming & fishing (organic food) High speed computing Atomic & hydrogen bombs … …

Contents Process intensification using particles for enhancing - Heterogeneous catalytic reaction Heat transfer using nanofluids Stabilisation/de-stabilisation of microparticles Summary

Process intensification using particles across length scales [1] Separation enhanced reaction processes - Le Chatalier’s principle (more effective for equilibrium controlled reactions) A + B = C + D Reactor C A+B in situ D separation through membrane, adsorption, chemical acceptor, etc.

Process intensification using particles across length scales [2] Separation enhanced reaction processes - SMR In-situ adsorption and ex-situ desoption Ding et al. (2005) Powder Technology, 153, 13-22. Koumpouras et al. (2007) Chem. Eng. Sci. 62, 5632-5637

Process intensification using particles across length scales [3] Separation enhanced reaction processes – current work: Steam reforming of glycerol C3H8O3 → 3CO + 4H2 Glycerol is a major by-product of biodiesel production EU currently produces approximately 6.8 billions litres of biodiesel per annum, which yields ~0.68 million tons of crude glycerol Although a small portion of the crude glycerol is purified for pharmaceutical and food applications, the majority of it is taken as waste With an increase in the biodiesel, production in the future, the amount of waste glycerol will certainly present a big challenge.

Process intensification using particles across length scales [4] Heat transfer enhancement using nanofluids Nanofluids: dilute suspensions of particles with at least one critical dimension smaller than ~100nm Nanofluids are a type of colloids, or more fashionably, functional nanoparticle suspensions! Ding et al. (2007) Adv. Powd. Tech., 18, 813-824 Chen et al. (2007) Chem. Phy. Lett., 444, 333-337 Ding et al. (2007) KONA, 25, 23-38

Process intensification using particles across length scales [5] Heat transfer enhancement using nanofluids Wen & Ding (2004) J. Thermophy. Heat Transfer 18, 481-485 Ding et al. (2007) Adv. Powd. Tech., 18, 813-824 Ding et al. (2007) KONA, 25, 23-38 Gao et al. (2007) Chem. Phy. Lett., 434, 297-300 Prasher et al. (2006) APL, 89, 143119 Chen et al. (2007) Chem. Phy. Lett., 444, 333-337 Chen et al. (2007) New J. Phys., 9, 367, 1-24 Chen & Ding (2008) Phy. Rev. Lett., submitted

Process intensification using particles across length scales [6] Heat transfer enhancement using nanofluids – forced convection: An industrial application in a small scale reacting system 3 x 3 x 100 mm reaction channels two integrated heat exchangers 100 mm distance between working and heat transfer fluids diffusion bonded 316 stainless steel Fan et al. (2008) Green Chemistry, in press

Forced Convection of Nanofluids (9) Process intensification using particles across length scales [7] Heat transfer enhancement using nanofluids – forced convection: An industrial application in a small scale reacting system Ethylene glycol based TiO2 nanofluids Mass flow rate = 5×10-3 kg s-1 Fan et al. (2008) Green Chemistry, in press

Process intensification using particles across length scales [8] Heat transfer enhancement using nanofluids – forced convection: An industrial application in a small scale reacting system Initial concentration of benzyl alcohol: 0.2 mol L-1, P = 8 bar, FLiquid = 1 mL min-1, FGas = 16 mL(STP) min-1, reaction channel size 100 mm × 3 mm × 3 mm Dynamic switch of chemical reactions Fan et al. (2008) Green Chemistry, in press

Process intensification using particles across length scales [9] Stabiliser of dispersions – highly industrially relevant Ding et al. (2007) unpublished work

Summary Particles can do the following if properly engineered – Heterogeneous catalytic reaction Heat transfer using nanofluids Stabilisation/de-stabilisation of microparticles Particles can do many more for us e.g. Seeded nucleation for nanoparticle production (impurity nanoparticles) Seeded granulation (micron particles) Enhancing cohesive powder flow (nanoparticles) Enhancing milling process (nanoparticles) Enhancing properties of composite materials (nanoparticles and microparticles) Enhanced wettability / spreadibility (nanoparticles) Enhancing surface cleaning Antimicrobial … …