RESEARCH ARTICLE

Preparation and crystallization kinetics of micron-sized Mg(OH)2 in a mixed suspension mixed product removal crystallizer

  • Xingfu SONG ,
  • Kefeng TONG ,
  • Shuying SUN ,
  • Ze SUN ,
  • Jianguo YU
Expand
  • National Engineering Research Center for Integrated Utilization of Salt Lake Resources, East China University of Science and Technology, Shanghai 200237, China

Received date: 27 Dec 2012

Accepted date: 26 Mar 2013

Published date: 05 Jun 2013

Copyright

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg

Abstract

Magnesium hydroxide is an important chemical, and is usually obtained from seawater or brine via precipitation process. The particle size distribution of magnesium hydroxide has great effects on the subsequent filtration and drying processes. In this paper, micron-sized magnesium hydroxide with high purity, large particle size and low water content in filter cake was synthesized via simple wet precipitation in a mixed suspension mixed product removal (MSMPR) crystallizer. The effects of reactant concentration, residence time and impurities on the properties of magnesium hydroxide were investigated by X-Ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Malvern laser particle size analyzer. The results show that NaOH concentration and residence time have great effects on the water content and particle size of Mg(OH)2. The spherical Mg(OH)2 with uniform diameter of about 30 μm was obtained with purity higher than 99% and water content less than 31%. Furthermore, the crystallization kinetics based on the population balance theory was studied to provide the theoretical data for industrial enlargement, and the simulation coefficients (R2) based on ASL model and C-R model are 0.9962 and 0.9972, respectively, indicating that the crystal growth rate of magnesium hydroxide can be well simulated by the size-dependent growth models.

Cite this article

Xingfu SONG , Kefeng TONG , Shuying SUN , Ze SUN , Jianguo YU . Preparation and crystallization kinetics of micron-sized Mg(OH)2 in a mixed suspension mixed product removal crystallizer[J]. Frontiers of Chemical Science and Engineering, 2013 , 7(2) : 130 -138 . DOI: 10.1007/s11705-013-1332-7

Acknowledgements

This work was supported by the Shanghai Natural Science Foundation (No. 09ZR147900) and the Program for New Century Excellent Talents in University (NCET-08-0776).
Nomenclature
a, bEquation parameter
B0Nucleation rate, No.·m-3·h-1
CVCoefficient of variation
dpParticle diameter in microns corresponding to the pth percentile cumulative volume, μm
d50Mean diameter of the particles, μm
D[4,3]Volume-weighted mean particle size, μm
fiVolume fraction of particle size i interval in the whole sizes, %
GCrystal growth rate, μm·h-1
G0Crystal nuclei growth rate, μm·h-1
LCrystal particle size, μm
ΔLDifference between particle size Li+1 and Li, μm
MiSuspension density of magnesium hydroxide slurry, g·cm-3
n0Nuclei population density, No.·m-3·μm-1
niCrystal population density of ith size fraction, No.·m-3·μm-1
RRelative coefficient
ViSingle crystal size volume with the diameterLi¯=Li+1+Li2, μm-3
ρDensity of magnesium hydroxide, g·mL-1
τResidence time, h
1
Tai C, Li R K Y. Studies on the impact fracture behaviour of flame retardant polymeric material. Materials & Design, 2001, 22(1): 15–19

DOI

2
Chen X L, Yu J, Guo S Y. Structure and properties of polypropylene composites filled with magnesium hydroxide. Journal of Applied Polymer Science, 2006, 102(5): 4943–4951

DOI

3
Cao H Q, Zheng H, Yin J F, Lu Y X, Wu S S, Wu X M, Li B J. Mg(OH)2 Complex Nanostructures with Superhydrophobicity and Flame Retardant Effects. Journal of Physical Chemistry C, 2010, 114(41): 17362–17368

DOI

4
Gui H, Zhang X H, Dong W F, Wang Q G, Gao J M, Song Z H, Lai J M, Liu Y Q, Huang F, Qiao J L. Flame retardant synergism of rubber and Mg(OH)2 in EVA composites. Polymer, 2007, 48(9): 2537–2541

DOI

5
Zhang S N, Cheng F Y, Tao Z L, Gao F, Chen J. Removal of nickel ions from wastewater by Mg(OH)2/MgO nanostructures embedded in Al2O3 membranes. Journal of Alloys and Compounds, 2006, 426(1-2): 281–285

DOI

6
Béarat H, McKelvy M J, Chizmeshya A V G, Sharma R, Carpenter R W. Magnesium hydroxide dehydroxylation/carbonation reaction processes: implications for carbon dioxide mineral sequestration. Journal of the American Ceramic Society, 2002, 85(4): 742–748

DOI

7
Kang J C, Schwendeman S P. Comparison of the effects of Mg(OH)2 and sucrose on the stability of bovine serum albumin encapsulated in injectable poly (D,L-lactide-co-glycolide) implants. Biomaterials, 2002, 23(1): 239–245

DOI

8
Kakaraniya S, Kari C, Verma R, Mehra A. Gas Absorption in Slurries of Fine Particles: SO2-Mg(OH)2-MgSO3 System. Industrial & Engineering Chemistry Research, 2007, 46(7): 1904–1913

DOI

9
Olanders B, Stroemberg D. Reduction of nitric oxide over magnesium oxide and dolomite at fluidized bed conditions. Energy & Fuels, 1995, 9(4): 680–684

DOI

10
Yan L, Zhuang J, Sun X M, Deng Z X, Li Y D. Formation of rod-like Mg(OH)2 nanocrystallites under hydrothermal conditions and the conversion to MgO nanorods by thermal dehydration. Materials Chemistry and Physics, 2002, 76(2): 119–122

DOI

11
Yoshida T, Tanaka T, Yoshida H, Funabiki T, Yoshida S, Murata T. Study of dehydration of magnesium hydroxide. Journal of Physical Chemistry, 1995, 99(27): 10890–10896

DOI

12
L'vov B V, Novichikhin A V, Dyakov A O. Mechanism of thermal decomposition of magnesium hydroxide. Thermochimica Acta, 1998, 315(2): 135–143

DOI

13
Yu J C, Xu A W, Zhang L Z, Song R Q, Wu L. W L. Synthesis and characterization of porous magnesium hydroxide and oxide nanoplates. Journal of Physical Chemistry B, 2004, 108(1): 64–70

DOI

14
Zou G L, Liu R, Chen W X, Xu Z D. Preparation and characterization of lamellar-like Mg(OH)2 nanostructures via natural oxidation of Mg metal in formamide/water mixture. Materials Research Bulletin, 2007, 42(6): 1153–1158

DOI

15
Ranjit K T, Klabunde K J. Solvent effects in the hydrolysis of magnesium methoxide, and the production of nanocrystalline magnesium hydroxide. An aid in understanding the formation of porous inorganic materials. Chemistry of Materials, 2005, 17(1): 65–73

DOI

16
Sun X T, Xiang L, Zhu W C, Liu Q. Influence of solvents on the hydrothermal formation of one‐dimensional magnesium hydroxide. Crystal Research and Technology, 2008, 43(10): 1057–1061

DOI

17
Utamapanya S, Klabunde K J, Schlup J R. Nanoscale metal oxide particles/clusters as chemical reagents. Synthesis and properties of ultrahigh surface area magnesium hydroxide and magnesium oxide. Chemistry of Materials, 1991, 3(1): 175–181

DOI

18
Hsu J P, Nacu A. Preparation of submicron-sized Mg(OH)2 particles through precipitation. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2005, 262(1-3): 220–231

DOI

19
Dong H B, Du Z P, Zhao Y H, Zhou D P. Preparation of surface modified nano-Mg(OH)2 via precipitation method. Powder Technology, 2010, 198(3): 325–329

DOI

20
Lv J P, Qiu L Z, Qu B J. Controlled growth of three morphological structures of magnesium hydroxide nanoparticles by wet precipitation method. Journal of Crystal Growth, 2004, 267(3-4): 676–684

DOI

21
Henrist C, Mathieu J P, Vogels C, Rulmont A, Cloots R. Morphological study of magnesium hydroxide nanoparticles precipitated in dilute aqueous solution. Journal of Crystal Growth, 2003, 249(1): 321–330

DOI

22
Wu Q L, Xiang L, Jin Y. Influence of CaCl2 on the hydrothermal modification of Mg(OH)2. Powder Technology, 2006, 165(2): 100–104

DOI

23
Yan C L, Xue D F, Zou L J, Yan X X, Wang W. Preparation of magnesium hydroxide nanoflowers. Journal of Crystal Growth, 2005, 282(3-4): 448–454

DOI

24
Alamdari A, Rahimpour M R, Esfandiari N, Nourafkan E. Kinetics of magnesium hydroxide precipitation from sea bittern. Chemical Engineering and Processing: Process Intensification, 2008, 47(2): 215–221

DOI

25
Söhnel O, Mareček J. Precipitation of magnesium hydroxide. Kristall und Technik, 1978, 13(3): 253–262

DOI

26
Turek M, Gnot W. Precipitation of magnesium hydroxide from brine. Industrial & Engineering Chemistry Research, 1995, 34(1): 244–250

DOI

27
Petric B, Petric N. Investigations of the Rate of Sedimentation of Magnesium Hydroxide Obtained from Sea Water. Industrial & Engineering Chemistry Process Design and Development, 1980, 19(3): 329–335

DOI

28
Song X F, Sun S Y, Zhang D K, Wang J, Yu J G. Synthesis and characterization of magnesium hydroxide by batch reaction crystallization. Frontiers of Chemical Science and Engineering, 2011, 5(4): 1–6

DOI

29
Dobrescu V, Păraşcu E, Pincovschi E. Continuous magnesium hydroxide precipitation. Crystal Research and Technology, 1987, 22(3): 327–338

DOI

30
Wang P P, Li C H, Gong H Y, Wang H Q, Liu J R. Morphology control and growth mechanism of magnesium hydroxide nanoparticles via a simple wet precipitation method. Ceramics International, 2011, 37(8): 3365–3370

DOI

31
Chen D H, Zhu L Y, Zhang H P, Xu K, Chen M C. Magnesium hydroxide nanoparticles with controlled morphologies via wet coprecipitation. Materials Chemistry and Physics, 2008, 109(2-3): 224–229

DOI

32
Wojcik J A, Jones A G. Experimental Investigation into Dynamics and Stability of Continuous MSMPR Agglomerative Precipitation of CaCO3 Crystals. Chemical Engineering Research & Design, 1997, 75(2): 113–118

DOI

33
McCabe W L. Crystal Growth in Aqueous Solutions1: II—Experimental. Industrial & Engineering Chemistry, 1929, 21(2): 112–119

DOI

34
McCabe W L. Crystal Growth in Aqueous Solutions1: I—Theory. Industrial & Engineering Chemistry, 1929, 21(1): 30–33

DOI

35
Abegg C F, Stevens J D, Larson M A. Crystal size distributions in continuous crystallizers when growth rate is size dependent. AIChE Journal. American Institute of Chemical Engineers, 1968, 14(1): 118–122

DOI

36
Canning T F, Randolph A D. Some aspects of crystallization theory: systems that violate McCabe's delta L Law. AIChE Journal. American Institute of Chemical Engineers, 1967, 13(1): 5–10

DOI

Outlines

/