Ferric chloride as an efficient and reusable catalyst for methanolysis of poly(lactic acid) waste

Liu, Huiqing; Song, Xiaoyan; Liu, Fusheng; Liu, Shiwei; Yu, Shitao

doi:10.1007/s10965-015-0783-6

Cited by 42 publications

(34 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Compared to other waste management strategies such as incineration and biodegradation, chemical recycling offers the greatest value with potential to reduce the cost of PLA and increase market uptake . Previous examples of PLA recycling processes include hydrolysis, alcoholysis, hydrogenation and hydrosilylation …”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Zinc Complexes for PLA Formation and Chemical Recycling: Towards a Circular Economy

et al. 2019

View full text Add to dashboard Cite

As eries of Zn II complexes, based on propylenediamineS chiff bases, have been prepared and fully characterized. X-ray crystallography and NMR spectroscopy identified significant differences in the solid and solution state for the Zn II species. All complexes have been applied to the ring-opening polymerization of l-lactidew ith emphasis on industrial conditions. High conversion and good molecularw eight control were generally achievablef or Zn(A-D) 2 ,a nd high-molecular-weight poly(lactic acid) (PLA) was prepared in 1min at a1 0000:1:33 [lactide]/ [Zn]/[BnOH] loading. The more active Zn II catalysts were also appliedt oP LA degradation to alkyl lactateu nder mild conditions. Zn(A-B) 2 demonstrated high activity and selectivity in this process with PLA being consumed within 1h at 50 8C. Zn(C-D) 2 were shown to be less active, and these observations can be relatedt ot he catalysts' structure and the degradation mechanism. Initialr esultsf or the degradation of poly(ethylene terephthalate) and mixed feeds are also presented, highlighting the broader applicability of the systems presented.Owing to the inevitable depletion of fossil fuel resources, and inherentc arbon emissions, alternatives to petrochemical plastics are desperately needed. [1] Poly(lactic acid) (PLA) is apotential replacement for fossil-fuel-derived plastics used for packaging applications. [2,3] PLA has the added advantageo f being biocompatible and therefore suitable for biomedical applications. [4,5] Because it is derived from annually harvested crops, PLA is biorenewable and has promising green credentials in terms of CO 2 emissions and life-cycle assessment. [6,7] High-molecular-weight PLA is preferentially prepared from the cyclic dimer of lactic acid, lactide (LA), through ring-opening polymerization (ROP). [8] CurrentP LA research seeks to reduce energy/material input of LA monomer synthesis, [9][10][11][12] demonstrate ande lucidate stereoselective initiation [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] and prepare robust initiators to compete with Sn(Oct) 2 under industrial conditions. [30][31][32][33][34] Plastic waste andp ollution are af urther 21 st century challenge forboth academia and industry.Although PLA is biodegradable under high-temperature industrial conditions, it will not readily degrade in the natural environmenta nd therefore will contribute to the millions of tonnes of waste in landfill and in oceans. [35][36][37] End-of-life plastic waste managementi s key to tackling this issue, andi ti si mperative this is addressed for all aspiring materials such as PLA. For PLA, chemical recycling is ap articularly attractive route because it can produce value-added products such as alkyl lactates, lactic acid and acrylic acid. [38,39] These can be usefuli nt heir own right or used to reform LA, and therefore PLA, to facilitate ac ircular-economy approach. Lactic acid, for example, is regarded as ap latform chemical, and alkyl lactates are considered green solvents. [40][41][42][43][44] The conversion of PLA ...

show abstract

Section: Methodsmentioning

confidence: 99%

“…Commercially available metal salts and precursors have been shown to facilitate the transesterification of PLA to alkyl lactates, typically methyl lactate (Me‐La) . Sobota and co‐workers have also shown the use of metallic precursors at relatively high temperatures, demonstrating a range of alcohols for transesterification .…”

Section: Methodsmentioning

confidence: 99%

Zinc Complexes for PLA Formation and Chemical Recycling: Towards a Circular Economy

et al. 2019

View full text Add to dashboard Cite

show abstract

“…[27][28][29] A number of different PLA transesterification methods have been reported in the literature. [30][31][32][33][34][35][36][37][38][39][40][41][42][43][44] DuPont possess a patent for PLA degradation in the presence of H 2 SO 4 , achieving high conversion (69-87%) to various lactate esters (R = Me, Et and n Bu) within 2 h between 150-190°C. 30 Coszach et al 17 demonstrated the hydrolysis of PLA to lactic acid, observing enhanced PLA dissolution and polymer separation with lactate esters as the solvent of choice.…”

Section: Introductionmentioning

confidence: 99%

Mono- and dimeric zinc(ii) complexes for PLA production and degradation into methyl lactate – a chemical recycling method

et al. 2020

View full text Add to dashboard Cite

show abstract

“…However, these approaches are not suitable for compositing because of the use of chemical compounds, which add to the environmental load. Enzymes [ 25 , 26 , 27 ] and metal compounds [ 28 ] have also been used as catalysts for PLA degradation. Some environmentally friendly materials such as clay can be used, but they increase the treatment time by several hours, necessitating larger plants for degradation.…”

Section: Introductionmentioning

confidence: 99%

Degradation of Polylactic Acid Using Sub-Critical Water for Compost

et al. 2020

View full text Add to dashboard Cite

Polylactic acid (PLA) is expected to replace many general-purpose plastics, especially those used for food packaging and agricultural mulch. In composting, the degradation speed of PLA is affected by the molecular weight, crystallinity, and microbial activity. PLA with a molecular weight of less than 10,000 has been reported to have higher decomposition rates than those with higher molecular weight. However, PLA degradation generates water-soluble products, including lactic acid, that decrease the pH of soil or compost. As acidification of soil or compost affects farm products, their pH should be controlled. Therefore, a method for determining suitable reaction conditions to achieve ideal decomposition products is necessary. This study aimed to determine suitable reaction conditions for generating preprocessed PLA with a molecular weight lower than 10,000 without producing water-soluble contents. To this end, we investigated the degradation of PLA using sub-critical water. The molecular weight and ratio of water-soluble contents (WSCs) affecting the pH of preprocessed products were evaluated through kinetic analysis, and crystallinity was analyzed through differential scanning calorimetry. Preprocessed PLA was prepared under the determined ideal conditions, and its characteristics in soil were observed. The results showed that the crystallization rate increased with PLA decomposition but remained lower than 30%. In addition, the pH of compost mixed with 40% of preprocessed PLA could be controlled within pH 5.4–5.5 over 90 days. Overall, soil mixed with the preprocessed PLA prepared under the determined ideal conditions remains suitable for plant growth.

show abstract

Ferric chloride as an efficient and reusable catalyst for methanolysis of poly(lactic acid) waste

Cited by 42 publications

References 27 publications

Zinc Complexes for PLA Formation and Chemical Recycling: Towards a Circular Economy

Zinc Complexes for PLA Formation and Chemical Recycling: Towards a Circular Economy

Mono- and dimeric zinc(ii) complexes for PLA production and degradation into methyl lactate – a chemical recycling method

Degradation of Polylactic Acid Using Sub-Critical Water for Compost

Contact Info

Product

Resources

About