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Table 2 Surface and mineralogical properties of gibbsite

From: Adsorption of aliphatic polyhydroxy carboxylic acids on gibbsite: pH dependency and importance of adsorbate structure

Property Measured and modelled data Ref. [31]
Puritya 99.4%  
Densitya 2.4 g cm−3  
Particle sizea (laser diffraction) D10 0.3–0.5 µm  
D50 0.7–1.2 µm  
D90 1.2–2.7 µm  
Surface areaa 10–12 m2 g−1 32 ± 25 m2 g−1b
Surface sites [≡SOH] (titration data) 120 mmol kg−1, 2.4 mmol L−1 (in batch) 8.2 ± 0.3 sites nm−2c
6.02–7.23 sites nm−2, mean: 6.57 sites nm−2
Isoelectric point (pHIEP) Diffuse double-layer model: pH: 8.28 9.1 ± 0.7d
Constant capacitance model: pH: 8.04
Surface protonation constants Diffuse double-layer model: pKintr (+): 6.60, pKintr(−): − 9.96 pKintr (+): 7.17e
Constant capacitance model: pKintr (+): 5.66, pKintr(−): − 10.41 pKintr (−): − 11.18e
pH (24 h, 5 mM NaClO4) 9.12 ± 0.01  
  1. aData provided by manufacturer
  2. bMean of 42 BET/N2 values, p. 60/61
  3. cMean of 6 values, p. 64
  4. dMean of 19 values, p. 64
  5. eBest fits obtained from double-layer model (including 13 titration curves from several studies)