000			02435nam a22002897a 4500
003			ZW-GwMSU
005			20230405155118.0
008			230405b |||||||| |||| 00| 0 eng d
040			_aMSU _cMSU _erda
100			_aCANALES, Raul Mollehuara
245			_aParticle-size effects on dissolved arsenic adsorption to an Australian laterite
264			_aVerlag _bSpringer _c2013
336			_2rdacontent _atext _btxt
337			_2rdamedia _aunmediated _bn
338			_2rdacarrier _avolume _bnc
440			_aEnvironmental earth sciences _vVolume , number ,
520			_aIn this study, arsenic adsorption to an Australian laterite has been examined for a particle-size range between 38 μm and 25 mm. The results show that particle size influences both kinetic and equilibrium characteristics of arsenic adsorption. The equilibrium adsorption capacity increases from around 100 mg kg−1 for laterite particles coarser than 4 mm, to around 160 mg kg−1 for laterite particles between 75 μm and 4 mm, and to over 200 mg kg−1 for laterite particles finer than 75 μm. The kinetic adsorption data can be fitted with the pseudo-second-order reaction model, in particular for finer particles where the film diffusion and/or surface reaction are important processes. The model-fitted rate constant remains steady for laterite particles coarser than 2 mm, increases moderately with particle size in the range between 75 μm and 2 mm, and increases dramatically for laterite particles finer than 75 μm. These arsenic adsorption behaviours can be explained by the relative importance of two particle-size-dependent processes: quick external-surface adsorption (more important for fine particles) and slow intraparticle adsorption (more important for coarse particles). Most of the external-surface adsorption completes in the first hour of the experiment. To apply the studied laterite for dissolved arsenic removal, it is recommended that fine particles, in particular finer than 75 μm, should be used if the contact time is the limitation, and that coarse particles, in particular 2–4 mm, should be used if sufficient contact time is available.
650			_anatural laterite
650			_aarsenic removal
650			_aadsorption
700			_aGUAN, Huade
700			_aBESTLAND, Erick
700			_aHUTSON, John
700			_aSIMMONS, Craig T.
856			_uhttps://doi.org/10.1007/s12665-012-1909-3
942			_2lcc _cJA
999			_c161616 _d161616