The step of washing {TAIL ~ the aqueous suspension} may be carried out by washing with {HEAD ~ an aqueous solution} containing an organic surfactant 
The step of washing { TAIL ~ the aqueous suspension } may be carried out by washing with { HEAD ~ an aqueous solution } containing an organic surfactant
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH