Search results for " Process intensification"
showing 4 items of 4 documents
Electrodialysis with Bipolar Membranes for the Sustainable Production of Chemicals from Seawater Brines at Pilot Plant Scale
2023
Environmental concerns regarding the disposal of seawater reverse osmosis brines require the development of new valorization strategies. Electrodialysis with bipolar membrane (EDBM) technology enables the production of acid and base from a salty waste stream. In this study, an EDBM pilot plant with a membrane area of 19.2 m2 was tested. This total membrane area results much larger (i.e., more than 16 times larger) than those reported in the literature so far for the production of HCl and NaOH aqueous solutions, starting from NaCl brines. The pilot unit was tested both in continuous and discontinuous operation modes, at different current densities (200-500 A m-2). Particularly, three differe…
Green Synthesis of Vanillin: Pervaporation and Dialysis for Process Intensification in a Membrane Reactor.
2019
In the present work, two different membrane processes (pervaporation and dialysis) are compared in view of their utilization in a membrane reactor, where vanillin, which is probably the most important aroma of the food industry, is synthesized in a green and sustainable way. The utilized precursor (ferulic acid, which is possibly a natural product from agricultural wastes) is partially oxidized (photocatalytically or biologically) and the product is continuously recovered from the reacting solution by the membrane process to avoid its degradation. It is observed that pervaporation is much more selective towards vanillin than dialysis, but the permeate flux of dialysis is much higher. Furthe…
Improvement of membrane performances to enhance the yield of vanillin in a pervaporation reactor.
2014
In membrane reactors, the interaction of reaction and membrane separation can be exploited to achieve a “process intensification”, a key objective of sustainable development. In the present work, the properties that the membrane must have to obtain this result in a pervaporation reactor are analyzed and discussed. Then, the methods to enhance these properties are investigated for the photocatalytic synthesis of vanillin, which represents a case where the recovery from the reactor of vanillin by means of pervaporation while it is produced allows a substantial improvement of the yield, since its further oxidation is thus prevented. To this end, the phenomena that control the permeation of bot…
Photocatalytic ozonation:Maximization of the reaction rate and control of undesired by-products
2014
In theso-calledphotocatalyticozonation(PO)synergisticeffectsbetweenphotocatalysisandozonation enhance therateofoxidationoforganiccompounds,thereforethisintegratedprocessisverypromising for useinwatertreatment.Inthepresentwork,itisdemonstratedthattheimprovementthatcanbe obtained bytheintegratedprocessincomparisonwiththeuncoupledprocessesdependsontherelative weight between photocatalysis and ozonation. In this respect, it has been found that a relatively low rate of photocatalysis (0.3 times the rate of ozonation)issufficienttogetthehighestsynergyandtomaximize the performancesintheoxidationofformate,theadoptedmodelorganiccompound.Thebenefitsof the couplingofphotocatalysistoozonationarenotlimi…