title: Esters production via carboxylates from anaerobic paper mill wastewater treatment.
abstract: This paper describes a new option for integrated recovery and esterification of carboxylates produced by anaerobic digestion at a pH above the pKa. The carboxylates (acetate, propionate, butyrate, valerate and lactate) are recovered using a strong anion exchange resin in the bicarbonate form, and the resin is regenerated using a CO2-expanded alcohol technique, which allows for low chemicals consumption and direct esterification. Paper mill wastewater was used to study the effect of pH and the presence of other inorganic anions and cations on the adsorption and desorption with CO2-expanded methanol. Calcium, which is present in paper mill wastewater, can cause precipitation problems, especially at high pH. Esters yields ranged from 1.08±0.04mol methyl acetate/mol of acetateinto 0.57±0.02mol methyl valerate/mol of valeratein.
authors.affiliation: Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands.
authors.forename: Carlos I
authors.initials: CI
authors.lastname: Cabrera-Rodríguez
authors.affiliation: Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands.
authors.forename: Mónica
authors.initials: M
authors.lastname: Moreno-González
authors.affiliation: Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands.
authors.forename: Florence A
authors.initials: FA
authors.lastname: de Weerd
authors.affiliation: Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands.
authors.forename: Vidhvath
authors.initials: V
authors.lastname: Viswanathan
authors.affiliation: Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands.
authors.forename: Luuk A M
authors.initials: LAM
authors.lastname: van der Wielen
authors.affiliation: Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands. Electronic address: A.J.J.Straathof@tudelft.nl.
authors.forename: Adrie J J
authors.initials: AJJ
authors.lastname: Straathof
mesh_terms: D002087:Butyrates; D004952:Esters; D010209:Paper; D011422:Propionates; D062065:Wastewater; D018508:Water Purification
chemical_list: D002087:Butyrates; D004952:Esters; D011422:Propionates; D062065:Wastewater
keywords: Anaerobic wastewater treatment; CO(2)-expanded methanol; Methyl carboxylates; Paper mill; Volatile fatty acids