Lactic acid conversion into acrylic acid and other products over natural and synthetic zeolite catalysts: theoretical and experimental studies

The valorization of waste from biomass currently arouses great interest. In the present study we concentrate on the design of innovative BEA zeolite catalysts with applied metal nanoparticles - copper, vanadium and manganese for the dehydration of lactic acid to acrylic acid. Th e ab initio method based on density functional theory (DFT) was used to calculate the electron structure of the analyzed molecules. The non-local generalized gradient corrected functionals GGA-RPBE was used to in order to account for electron exchange and correlation. The cluster model was represented by a hierarchical zeolite M2Al2Si12O40H22 (M = Cu, V, Mn). Th e stabilization of the M-Ob-M dimer complex in the hierarchical structure of BEA, mechanism of adsorption of lactic acid on BEA zeolite with applied metal dimers and formation of acrylic acid on these zeolites were investigated. Th e examined metals form stable dimers interconnected by a bridge oxygen (Ob). Adsorption of lactic acid takes place in the vicinity of a dimer of M-Ob-M.The dehydration of lactic acid to acrylic acid in all cases consists in the separation of the hydroxyl group and creating a connection with a metal center of dimer and disconnection of a single hydrogen atom from the methyl group and its interaction with bridge oxygen of dimer.

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Comparison of Synthetic and Natural Zeolite Catalysts’ Behavior in the Production of Lactic Acid and Ethyl Lactate from Biomass-Derived Dihydroxyacetone

Catalysts ◽

10.3390/catal11081006 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1006

Author(s):

Natalia Sobuś ◽

Izabela Czekaj

Keyword(s):

Lactic Acid ◽

Natural Zeolite ◽

Carbon Balance ◽

Zeolite Beta ◽

Synthetic Zeolite ◽

Zeolite Catalysts ◽

Ethyl Lactate ◽

Hydrothermal Conditions ◽

Natural Clinoptilolite ◽

Zeolite Modification

This article presents the results of the conversion of dihydroxyacetone (DHA) to lactic acid (LA) with the use of zeolite catalysts. For this purpose, synthetic zeolite beta (BEA) and natural clinoptilolite (CLI) were used as a matrix. The zeolites were modified with various metals (Sn, Fe, Cu and Zn) during ion exchange under hydrothermal conditions. The DHA conversion process with the participation of metal-functionalized zeolites allowed us to obtain intermediates, i.e., pyruvic aldehyde (PAL), which during the further reaction was transformed into a mixture of products such as ethyl lactate (EL), pyruvic aldehyde (PA), lactic acid and ethyl acetate (EA). The best selectivity towards lactic acid was achieved using Sn-CLI (100%) > Na-BEA (98.7%) > Sn-BEA (95.9%) > Cu-BEA (92.9%), ethyl lactate using Cu-CLI, and pyruvic aldehyde using the Zn-BEA catalyst. In the case of a natural zeolite, modification with Sn is promising for obtaining a pure lactic acid with a relatively good carbon balance.

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Plastic waste to liquid oil through catalytic pyrolysis using natural and synthetic zeolite catalysts

Waste Management ◽

10.1016/j.wasman.2017.08.032 ◽

2017 ◽

Vol 69 ◽

pp. 66-78 ◽

Cited By ~ 64

Author(s):

R. Miandad ◽

M.A. Barakat ◽

M. Rehan ◽

A.S. Aburiazaiza ◽

I.M.I. Ismail ◽

...

Keyword(s):

Catalytic Pyrolysis ◽

Synthetic Zeolite ◽

Plastic Waste ◽

Zeolite Catalysts ◽

Natural And Synthetic

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EVALUATION OF HYDROPHILIC GLOBULES WITH SODIUM ALGINATE CONTAINING A LACTIC ACID– CHITOSAN COMPLEX

Progress on Chemistry and application of Chitin and its Derivatives ◽

10.15259/pcacd.26.015 ◽

2021 ◽

Vol 26 ◽

pp. 170-177

Author(s):

Katarzyna Małolepsza-Jarmołowska ◽

Keyword(s):

Lactic Acid ◽

Rheological Properties ◽

Sodium Alginate ◽

Contact Time ◽

Experimental Studies ◽

Vaginal Mucosa

An important issue in the treatment of vaginitis is the amount of time the drug remains on the vaginal mucosa. If the contact time is too short, the drug cannot work effectively to ensure the correct pH in the vaginal environment. This study evaluated formulations of globules containing sodium alginate, lactic acid and chitosan with different pH and rheological properties. The experimental studies revealed that it is possible to produce a preparation with optimal pharmaceutical and application properties. The use of an appropriate ratio of lactic acid to chitosan in the complex and the appropriate concentration of sodium alginate produces a preparation with excellent properties to coat the surface of the vaginal mucosa.

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Lactic Acid Conversion to Acrylic Acid Over Fluoride-Substituted Hydroxyapatites

Frontiers in Chemistry ◽

10.3389/fchem.2020.00421 ◽

2020 ◽

Vol 8 ◽

Cited By ~ 1

Author(s):

Robert Wojcieszak ◽

Thomas Bonnotte ◽

Sébastien Paul ◽

Benjamin Katryniok ◽

Franck Dumeignil

Keyword(s):

Lactic Acid ◽

Acrylic Acid

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Catalytic dehydration of lactic acid to acrylic acid using calcium hydroxyapatite catalysts

Green Chemistry ◽

10.1039/c3gc40144h ◽

2013 ◽

Vol 15 (5) ◽

pp. 1211 ◽

Cited By ~ 107

Author(s):

Vidhya C. Ghantani ◽

Samadhan T. Lomate ◽

Mohan K. Dongare ◽

Shubhangi B. Umbarkar

Keyword(s):

Lactic Acid ◽

Acrylic Acid ◽

Calcium Hydroxyapatite

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A New Method of Relating Airflow Measurements of Fineness and Maturity to the Geometrical Properties of the Cotton Fiber

Textile Research Journal ◽

10.1177/004051757604601112 ◽

1976 ◽

Vol 46 (11) ◽

pp. 835-841 ◽

Cited By ~ 6

Author(s):

S. G. Stephens

Keyword(s):

Lactic Acid ◽

Cotton Fiber ◽

Isopropyl Alcohol ◽

Experimental Studies ◽

New Method ◽

Fiber Types ◽

Geometrical Properties ◽

Wide Range ◽

Fiber Dimensions ◽

Coiled Fiber

A new method of estimating cotton fiber dimensions is developed, based on the geometrical properties of a loosely-coiled fiber. The theoretical principles are supported by experimental studies based on actual microscopic measurements of a wide range of cotton fiber types. The procedure involved cutting short segments ( ca. 2 mm) from the midregions of the fibers and mounting them in minimal amounts of a suitable clearing/mounting medium (3 parts 85% lactic acid: 1 part isopropyl alcohol). Fibers so prepared can be measured more accurately then dry fibers, although the mounting medium induces a slight swelling of the fiber walls.

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