Optimization of nitric acid properties for chemical recycling of cadmium from spent Ni-Cd batteries

An approach to chemical recycling of carbon fiber reinforced epoxy resin cured with amine has been investigated. Amine cured epoxy resin was decomposed totally when it was treated with nitric acid solution under certain conditions. The impacts of nitric acid concentration and decomposition temperature on recycling method were studied with decomposing time and the performance of carbon fiber as indexes. Epoxy resin matrix decomposed entirely after 23hrs at 95°C in the 8mol/L nitric acid solution. Scanning electron microscopy analysis (SEM) and monofilament strength were used to characterize the recycled carbon fibers.

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Removal of disperse dye from alcoholysis products of waste PET fabrics by nitric acid-modified activated carbon as an adsorbent: Kinetic and thermodynamic studies

Textile Research Journal ◽

10.1177/0040517520909510 ◽

2020 ◽

Vol 90 (17-18) ◽

pp. 2058-2069 ◽

Cited By ~ 1

Author(s):

Mengjuan Li ◽

Jing Lu ◽

Xiaoqiang Li ◽

Mingqiao Ge ◽

Yonggui Li

Keyword(s):

Activated Carbon ◽

Nitric Acid ◽

Chemical Recycling ◽

Modified Activated Carbon ◽

Poly Ethylene Terephthalate ◽

Elemental Analyses ◽

Different Temperatures ◽

Pseudo Second Order ◽

Poly Ethylene ◽

Oxygen Groups

Decolorization technology is a critical problem of high-quality chemical recycling and recovery of waste poly(ethylene terephthalate) (PET) textiles. In order to deal with this problem, nitric acid-modified activated carbon (AC-HNO3) was utilized as an adsorbent for removal of C.I. Disperse Red 60 (DR60) from the glycolysis products of waste PET fabrics. The glycolysis product was bis(2-hydroxyethyl) terephthalate (BHET). The pore structure and surface properties of AC and AC-HNO3 samples were characterized by N2 adsorption, differential thermogravimetric analysis (DTG) and elemental analyses (EA). Modification with nitric acid increased the amount of oxygen groups of the activated carbon from 12.3% to 18.0% and enhanced the electrostatic attraction between dye molecules and activated carbon. The average color removal ratio of DR60 on AC-HNO3 increased into 97.6 ± 0.5%, which is better than that on raw AC (85.0 ± 1.6%). Relative whiteness of BHET increased from 40.3 ± 0.9% to 98.3 ± 1.1%. The adsorption kinetics for DR60 on the AC-HNO3 were studied using pseudo-first order and pseudo-second order models and fitted to the latter well ( R2 = 0.9999). To investigate the adsorption equilibrium behavior, Freundlich and Langmuir models were examined. The results showed that the Langmuir model provided better correlation ( qmax = 163.9 mg/g). The adsorption isotherms at different temperatures were used for the determination of thermodynamic parameters. Based on the data of Δ G0 , Δ H0 and Ea, the adsorption process was physisorption.

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Chemical recycling bisphenol A type epoxy resin based on degradation in nitric acid

10.1109/ecodim.2003.1322687 ◽

2003 ◽

Cited By ~ 1

Author(s):

Dilafruz ◽

Kubouchi ◽

Dang ◽

Sembokuya ◽

Tsuda

Keyword(s):

Nitric Acid ◽

Bisphenol A ◽

Epoxy Resin ◽

Chemical Recycling

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Chemical recycling of glass fiber reinforced epoxy resin cured with amine using nitric acid

Polymer ◽

10.1016/j.polymer.2004.12.035 ◽

2005 ◽

Vol 46 (6) ◽

pp. 1905-1912 ◽

Cited By ~ 93

Author(s):

Weirong Dang ◽

Masatoshi Kubouchi ◽

Hideki Sembokuya ◽

Ken Tsuda

Keyword(s):

Nitric Acid ◽

Glass Fiber ◽

Epoxy Resin ◽

Chemical Recycling ◽

Fiber Reinforced ◽

Glass Fiber Reinforced

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Chemical recycling bisphenol A type epoxy resin based on degradation in nitric acid

2003 IEEE 58th Vehicular Technology Conference. VTC 2003-Fall (IEEE Cat. No.03CH37484) ◽

10.1109/vetecf.2003.239830 ◽

2003 ◽

Author(s):

K. Dilafruz ◽

M. Kubouchi ◽

W. Dang ◽

H. Sembokuya ◽

K. Tsuda

Keyword(s):

Nitric Acid ◽

Bisphenol A ◽

Epoxy Resin ◽

Chemical Recycling

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3. On the Products of the Oxidation of Dimethyl-Thetine, and its Derivatives

Proceedings of the Royal Society of Edinburgh ◽

10.1017/s037016460003025x ◽

1875 ◽

Vol 8 ◽

pp. 508-509

Author(s):

Crum Brown ◽

E. A. Letts

Keyword(s):

Nitric Acid ◽

Sulphuric Acid ◽

The Other ◽

Soluble Salt ◽

Acid Properties ◽

Basic Properties ◽

The One ◽

Two Bodies ◽

Dilute Nitric Acid

The difficulty experienced in determining the sulphur contained in the compounds of dimethyl-thetine (described in a former communication) by oxidation to sulphuric acid, induced the authors to study the effects of various oxidising agents on these compounds.By acting on nitrate of dimethyl-thetine with dilute nitric acid, two bodies are produced. The one has acid properties, and forms a well-marked soluble salt with baryta. The other has neither acid nor basic properties. It crystallises in very beautiful needles from a hot solution in alcohol.

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Decomposition of GFRP in Nitric Acid and Hydrogen Peroxide Solution for Chemical Recycling

Progress in Rubber Plastics and Recycling Technology ◽

10.1177/147776060201800102 ◽

2002 ◽

Vol 18 (1) ◽

pp. 49-68 ◽

Cited By ~ 5

Author(s):

Weirong Dang ◽

Masatoshi Kubouchi ◽

Takuya Maruyama ◽

Hideki Sembokuya ◽

Ken Tsuda

Keyword(s):

Hydrogen Peroxide ◽

Nitric Acid ◽

Glass Fiber ◽

Picric Acid ◽

Hydrogen Peroxide Solution ◽

Size Exclusion ◽

Chemical Recycling ◽

Chemical Structures ◽

Glass Fiber Reinforced ◽

Exclusion Chromatography

Decomposition of Glass Fiber Reinforced epoxy resin cured with amine in nitric acid and hydrogen peroxide solution has been investigated. After specimens were immersed in above solutions for a specific time, glass fiber could be separated from matrix resulting from the decomposition of matrix resin. The chemical structures and molecular weight distributions of the decomposed products were analyzed by FT-IR and size exclusion chromatography (SEC). When nitric acid was used, the resin was mainly decomposed into 2,4,6-trinitrophenol (picric acid) and quasi-monomer. In the case of hydrogen peroxide, the backbone of resin was broken into monomer and dimer, or peracetic acid, depending on immersion time. On the other hand, glass fiber exhibited low corrosion resistance to nitric acid, while it was hardly degraded in hydrogen peroxide. Based on analyzing the decomposed products and observing the degradation of glass fiber, the chemical recycling method on GFRP was proposed.

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