Browsing by Keyword "Purification"
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Item Efficient P(3HB) extraction from Burkholderia sacchari cells using non-chlorinated solvents(2015-11-15) Rosengart, A.; Cesário, M.T.; de Almeida, M. Catarina M.D.; Raposo, Rodrigo S.; Espert, A.; Díaz de Apodaca, E.; da Fonseca, M. Manuela R.; Alimentación SostenibleA technique using safer, non-chlorinated organic solvents for the extraction of poly-3-hydroxybutyrate (P(3HB)) from bacterial cells was developed, aiming to attain high recovery yields and purities. Some solvents were selected from the GlaxoSmithKline guide as sustainable industrial solvents and the solubility of P(3HB) calculated using predictive equations from literature. Based on the calculated solubility values, anisole, cyclohexanone and phenetole were tested as extraction solvents and the relevant process variables (extraction temperature, extraction time and mass of cells/solvent volume ratio) were addressed. Polymer recovery yields of 97% and 93% were obtained with anisole and cyclohexanone, respectively, at 120–130 °C using a cell/solvent ratio of 1.5% (w/v). Maximum polymer purities using these experimental conditions were 98% for both solvents. The recovery yield and the polymer purity attained with chloroform (reference solvent) were 96 and 98%, respectively. Higher cell/solvent ratios of 6.0% (w/v) showed slightly lower recovery yields and purities. The average molecular weight and the thermal properties of the polymers extracted with the alternative solvents were fully comparable to those of the polymers obtained by chloroform extraction, demonstrating that the applied conditions did not significantly alter the properties of the extracted P(3HB).Item Hydrogen permeation and stability in ultra-thin Pd-Ru supported membranes(2020-03-04) Liu, Jinxia; Bellini, Stefano; de Nooijer, Niek C.A.; Sun, Yu; Pacheco Tanaka, David Alfredo; Tang, Chunhua; Li, Hui; Gallucci, Fausto; Caravella, Alessio; Tecnalia Research & Innovation; TECNOLOGÍA DE MEMBRANAS E INTENSIFICACIÓN DE PROCESOSIn this paper, we report the performance of supported PdRu membranes for possible applications to hydrogen purification and/or production. For this purpose, we fabricated three ultra-thin α-alumina-supported membranes by combined plating techniques: a PdAg membrane (3 μm-thick ca.) and two PdRu (1.8 μm-thick ca.). The former is set as a benchmark for comparison. The membranes were characterised using different methodologies: permeation tests, thermal treatment and SEM analysis. Preliminary leakage tests performed with nitrogen has revealed that the two PdRu membranes, namely PdRu#1 and PdRu#2, show a non-ideal (non-infinite) selectivity, which is relatively low for the former (around 830 at 400 °C) and sufficiently high for the latter (2645 at 400 °C). This indicates a relevant presence of defects in the PdRu#2 membrane, differently from what observed for the PdAg and PdRu#1 ones. The permeation tests show that the hydrogen permeating flux is stable up to around 550 °C, with an apparently unusual behaviour at higher temperatures (600 °C), where we observe a slightly decrease of hydrogen flux with an increase of the nitrogen one. Moreover, a peculiar bubble-shaped structure is observed in the metal layer of all membranes after usage by means of SEM image analysis. This is explained by considering the effect of the Pd-alloy grain surface energy, which tends to minimise the exposed surface area of the grain interface by creating sphere-like bubble in the lattice, similar to what occurs for soap bubbles in water. The above-mentioned decrease in hydrogen flux at 600 °C is explained to be caused by the bubble formation, which pushes the alloy deeper in the support pores.Item VALORISATION OF HYDROLYSIS LIGNIN REST FROM BIOETHANOL PILOT PLANT: PROCESS DEVELOPMENT AND UPSCALING: PROCESS DEVELOPMENT AND UPSCALING(2020-11-15) Svensson, Ingemar; Roncal, Tomás; De Winter, Karel; Van Canneyt, Anoek; Tamminen, Tarja; Mikkelson, Atte; Barrio, Aitor; Tecnalia Research & Innovation; BIOECONOMÍA Y CO2The aim of this work has been to find a scalable process to purify lignin and separate the cellulose-rich fraction from a poplar wood hydrolysis rest produced at a bioethanol pilot-plant. At initial laboratory optimization, a mild extraction of lignin was performed with 1 M NaOH at 90 °C to dissolve the lignin, that was further precipitated with sulfuric acid and this formed an easily filtrable powder. The main sub-product was a solid residue enriched in cellulose, which was successfully saccharified and tested for its fermentability. Further upscaling of the method was done at Bio Based Europe Pilot Plant (BBEPP) in Belgium. In a first run 14.2 kg of purified poplar lignin was obtained and in a second run 128.6 kg was obtained. The wet fiber residue was processed by washing and enzymatic hydrolysis to obtain, 26.7 kg of concentrated sugar solution with 509.4 g/L of glucose.