Kinetic study on the impact of acidity and acid concentration on the formation of 5-hydroxymethylfurfural (HMF), humins, and levulinic acid in the hydrothermal conversion of fructose

AbstractSeveral biofabrication methods are being investigated to produce scaffolds that can replicate the structure of the extracellular matrix. Direct-write, near-field electrospinning of polymer solutions and melts is one such method which combines fine fiber formation with computer-guided control. Research with such systems has focused primarily on synthetic polymers. To better understand the behavior of biopolymers used for direct-writing, this project investigated changes in fiber morphology, size, and variability caused by varying gelatin and acetic acid concentration, as well as, process parameters such as needle gauge and height, stage speed, and interfiber spacing. Increasing gelatin concentration at a constant acetic acid concentration improved fiber morphology from large, planar structures to small, linear fibers with a median of 2.3 µm. Further varying the acetic acid concentration at a constant gelatin concentration did not alter fiber morphology and diameter throughout the range tested. Varying needle gauge and height further improved the median fiber diameter to below 2 µm and variability of the first and third quartiles to within +/-1 µm of the median for the optimal solution combination of gelatin and acetic acid concentrations. Additional adjustment of stage speed did not impact the fiber morphology or diameter. Repeatable interfiber spacings down to 250 µm were shown to be capable with the system. In summary, this study illustrates the optimization of processing parameters for direct-writing of gelatin to produce fibers on the scale of collagen fibers. This system is thus capable of replicating the fibrous structure of musculoskeletal tissues with biologically relevant materials which will provide a durable platform for the analysis of single cell-fiber interactions to help better understand the impact scaffold materials and dimensions have on cell behavior.

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Catalytic Production of Levulinic Acid (LA) from Actual Biomass

Molecules ◽

10.3390/molecules24152760 ◽

2019 ◽

Vol 24 (15) ◽

pp. 2760 ◽

Cited By ~ 12

Author(s):

Michela Signoretto ◽

Somayeh Taghavi ◽

Elena Ghedini ◽

Federica Menegazzo

Keyword(s):

Green Chemistry ◽

Levulinic Acid ◽

Complex Structure ◽

Reaction System ◽

Catalytic Conversion ◽

Crucial Issue ◽

Recent Approach ◽

Different Types ◽

Pros And Cons ◽

The Impact

Catalytic conversion of actual biomass to valuable chemicals is a crucial issue in green chemistry. This review discusses on the recent approach in the levulinic acid (LA) formation from three prominent generations of biomasses. Our paper highlights the impact of the nature of different types of biomass and their complex structure and impurities, different groups of catalyst, solvents, and reaction system, and condition and all related pros and cons for this process.

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Kinetic Studies on the Impact of Pd Addition to Ru/TiO2 Catalyst: Levulinic Acid to γ-Valerolactone under Ambient Hydrogen Pressure

Industrial & Engineering Chemistry Research ◽

10.1021/acs.iecr.0c01270 ◽

2020 ◽

Vol 59 (39) ◽

pp. 17279-17286 ◽

Cited By ~ 1

Author(s):

Guangyue Xu ◽

Chuang Li ◽

Tianyu Deng ◽

Chenguang Wang ◽

Ying Zhang ◽

...

Keyword(s):

Levulinic Acid ◽

Hydrogen Pressure ◽

Kinetic Studies ◽

Tio2 Catalyst ◽

The Impact

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Autologous 111 Indium-Oxinate-Labelled Platelet Sequestration Study in Patients with Immune Thrombocytopenia Treated By Thrombopoietic Receptor-Agonists

Blood ◽

10.1182/blood.v128.22.2555.2555 ◽

2016 ◽

Vol 128 (22) ◽

pp. 2555-2555

Author(s):

Matthieu Mahevas ◽

Sandrine Van Eeckhoudt ◽

Guillaume Moulis ◽

Christine Dosquet ◽

Marc Michel ◽

...

Keyword(s):

Platelet Count ◽

Life Span ◽

Kinetic Study ◽

Immune Thrombocytopenia ◽

Complete Response ◽

Splenic Sequestration ◽

Platelet Production ◽

Receptor Agonists ◽

Day Range ◽

The Impact

Abstract Introduction In immune thrombocytopenia (ITP), isotopic assessment of the site of platelet destruction using autologous111Indium-oxinate-labelled platelet sequestration study could be an helpful parameter to determine whether or not to perform splenectomy. Two independent studies have suggested that a purely splenic sequestration could be a significant predictive factor of long-term complete response after splenectomy. An increasing number of patients receives thrombopoietic receptor-agonists (TPO-RAs) but such treatments are not curative and therefore do not necessarily prevent from considering splenectomy in the course of ITP. TPO-RAs increase platelet production by inducing proliferation and differentiation of the megakaryocyte lineage. We have only very few data evaluating the impact of TPO-RAs, on mean platelet life span (MPLS), platelet production and platelet site of destruction. The aim of this study was to assess these parameters and clinical outcome of patients treated with TPO-RAs who underwent kinetic study of autologous111Indium-oxinate-labelled platelet. Patients and Methods We carried out a retrospective study in the Ile de France region, between 2008 and 2016. Patients were retrospectively selected from a prospective clinical database at the Cellular Biology Department of Saint Louis Hospital. We selected adult patients with definite ITP according to the international criteria. The isotopic method used to study platelet lifespan was previously described. Analyses were based on the radioactivity accumulation slopes in the hepatic or splenic area. We excluded patients who had received less than 3Mbeq of 111In. Data from patients' medical charts were collected using the standardized form of the Referral Center for Adult ITP. Complete response (CR) and Response (R) were defined according to standardized international criteria: platelet count > 30x 109/L with at least a doubling of the baseline value or >100 x 109/L. Results of platelet kinetic study from patients treated with TPO-RAs were compared with those from patients receiving no treatments. Results Two hundred and fifty three adults ITP patients were included. At the time of platelet kinetic study, 24 patients (10 men/14 women) with a median age of 63 years [range: 22-83] were treated with TPO-RAs (romiplostim n= 10, eltrombopag n = 14) and 229 (81 men/148 women) had no treatment. Among the TPO-RAs treated patients, some also received low dose steroids (n=6), dapsone (n=1) or intravenous immunoglobulins (n=2) at least two weeks before the kinetic study. Three were newly diagnosed, 9 had persistent ITP and 12 chronic ITP. The median platelet count was 62 x109/L [range: 22-175], and 7 patients had a platelet count > 100 x109/L. The median Mean Platelet Life Span (MPLS) was reduced in both groups (1.44 day [range: 0.4-7.5] (normal: 7-10) in patients treated with TPO-RAs), but was significantly higher in untreated patients (2.3 day [0.4-11], p = 0.004). The median turnover platelets ratio was increased in both groups (48% per day [range: 11-173] in patients treated with TPO-RAs), but was significantly lower in untreated patients (30% per day [range: 0.8-247]). Ratio of platelet production was significantly increased in patients treated with TPO-RAs (median: 2, [range: 0.1-5.0]) compared with untreated patients (median: 0.84, [range: 0.1-85.0]). Repartition of the site of platelet sequestration was similar in the two groups, 12 (50%) patients treated with TPO-RAs had a splenic uptake, versus 112 (49.1%) in untreated patients, and 2 (20%) patients treated with TPO-RAs had an hepatic uptake versus 9 (3.9%) in untreated patients. A splenectomy was performed in 9 out of the 12 patients with a purely splenic sequestration. After a median follow-up of 26 months [range 0-53], 8 (88%) had achieved CR and 1 had relapsed 5 months after splenectomy. Conclusion Our study shows that despite an increase production and turnover of platelets due to the stimulation of the megakaryopoiesis by TPO-RAs, the MPLS was clearly reduced and the repartition of platelet sequestration was not modified in patients receiving these drugs. Moreover, it would seem that a purely splenic sequestration is also predictive of CR after splenectomy in this group of patients. More importantly platelet kinetic study can be used in patients treated with TPO-RAs to position the splenectomy in the therapeutic management. Disclosures No relevant conflicts of interest to declare.

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Hydrothermal conversion of glucose to levulinic acid using multifunctional ionic liquids: effects of metal ion co-catalysts on the product yield

New Journal of Chemistry ◽

10.1039/c7nj03146g ◽

2018 ◽

Vol 42 (1) ◽

pp. 228-236 ◽

Cited By ~ 15

Author(s):

Komal Kumar ◽

Firdaus Parveen ◽

Tanmoy Patra ◽

Sreedevi Upadhyayula

Keyword(s):

Ionic Liquids ◽

Catalytic System ◽

Metal Ion ◽

Levulinic Acid ◽

Product Yield ◽

Metal Salts ◽

Hydrothermal Conversion ◽

Co Catalysts ◽

Platform Chemicals ◽

Acidic Ionic Liquids

An efficient catalytic system comprising Bronsted acidic ionic liquids and Lewis acidic metal salts for hydrothermal glucose conversion to platform chemicals.

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Effect of Hydrochloric Acid Concentration on the Conversion of Sugarcane Bagasse to Levulinic Acid

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/299/1/012092 ◽

2018 ◽

Vol 299 ◽

pp. 012092 ◽

Cited By ~ 3

Author(s):

Heni Anggorowati ◽

Siti Jamilatun ◽

Rochim B. Cahyono ◽

Arief Budiman

Keyword(s):

Hydrochloric Acid ◽

Acid Concentration ◽

Sugarcane Bagasse ◽

Levulinic Acid ◽

Hydrochloric Acid Concentration

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Hydrothermal Conversion of Cattle Manure to Biooil: Biooil Definitions

Volume 8: Engineering to Address Climate Change; Sustainable Products and Processes ◽

10.1115/imece2009-10286 ◽

2009 ◽

Author(s):

Sudong Yin ◽

Ryan Dolan ◽

Zhongchao Tan

Keyword(s):

Chemical Properties ◽

Cattle Manure ◽

Hydrothermal Conversion ◽

Elemental Compositions ◽

High Heating Value ◽

High Heating ◽

Extraction Solvents ◽

The Mean ◽

Main Components ◽

The Impact

A number of researchers have reported that biooil was produced through hydrothermal conversion of different types of biomass. However, it is difficult to evaluate and compare these biooils in terms of yields and chemical properties. They applied different organic solvents to extract biooil from products after hydrothermal conversion of biomass. The purpose of this study is to assess the impact of extraction solvents on the quantity and chemical structure of biooil. Cattle manure was used as one type of biomass feedstock for biooil production. And dichloromethane (CH2Cl2), chloroform (CHCl3) and diethyl ether (C4H10O) were used for biooil extraction. Results showed that extraction solvents influenced biooil yields. The highest biooil yield of 48.78 wt% of volatile content of cattle manure was obtained when using CH2Cl2 solvent. The main components of biooil extracted by CH2Cl2 and CHCl3 were ketones and carboxylic acids, while those extracted by C4H10O were aromatic chemicals. In terms of elemental compositions and high heating values of biooil, no statistically apparent differences were caused by different solvents. The mean elemental compositions (by weight) of biooils were carbon of 73.79%, hydrogen of 8.18%, nitrogen of 4.38% and oxygen of 13.65%. And the mean high heating value of biooil was 36.74 MJ/kg.

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Modeling wormhole formation in digital rock samples: the role of segmentation and permeability-porosity relationships

10.5194/egusphere-egu2020-996 ◽

2020 ◽

Author(s):

Rishabh Prakash Sharma ◽

Max P. Cooper ◽

Anthony J.C. Ladd ◽

Piotr Szymczak

Keyword(s):

Acid Concentration ◽

Flow Rate ◽

Reactive Transport ◽

Pore Space ◽

Small Variation ◽

Power Laws ◽

Linear Interpolation ◽

Constitutive Relationship ◽

Dissolution Experiment ◽

The Impact

In this work we have investigated numerically the formation of channelised dissolution patterns, termed &#8220;wormholes&#8221;, using initial pore geometries generated from tomographic images of limestone cores. We have employed an OpenFOAM-based Darcy-scale numerical solver,&#160; porousFoam, which combines a Darcy/Darcy-Brinkman flow solver and a reactive transport solver in an evolving pore space. Simulated geometries, of both final and intermediate steps, are compared to dissolution experiments on samples the initial pore geometry is generated from, with the same acid concentration and flow rate applied.&#160;The initial condition of porosity distribution is set from X-Ray Computed Microtomography (XCMT) images via three phase segmentation into macroporosity, microporosity, and grain regions. Porosity values for microporous regions are set using linear interpolation between pore and grain grayscale values [1]. The inlet boundary conditions of flow rate and acid concentration are set as in the dissolution experiment. To test the effect of the permeability-porosity constitutive relationship we have investigated several options including power laws of varying exponent, and the Carman-Kozeny relation. We have also analyzed the impact of using Darcy versus Darcy-Brinkman flow solvers. Despite a qualitatively similar appearance to experimental results, the simulated wormholes are usually significantly thicker than their experimental counterparts, a fact noted by other researchers as well [2]. We comment on possible reasons for this discrepancy and on the limitations of Darcy-scale solvers in general. Additionally, we find that higher exponents in the power law makes the numerical dissolution very sensitive to grayscale threshold values as a small variation in this value changes the path of the wormhole.&#160;[1] Luquot, L., Rodriguez, O., and Gouze, P.: Experimental characterization of porosity structure and transport property changes in limestone undergoing different dissolution regimes, Transport Porous Med., 101, 507&#8211;532, 2014.[2] Yue Hao, Megan Smith, Yelena Sholokhova, Susan Carroll, CO2-induced dissolution of low permeability carbonates. Part II: Numerical modeling of experiments, Advances in Water Resources, 62, 388-408, 2013&#160;

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