Assessing operational stability in condensed-mode fluidized bed reactor for linear low density polyethylene production: Insights from a thermoregulating water valve malfunction analysis

Journal of Elastomers & Plastics, Journal Year: 2024, Volume and Issue: 56(5), P. 661 - 674

Published: May 30, 2024

The reliability of thermal regulation systems is crucial for ensuring the stability condensed-mode gas-phase fluidized bed reactors (FBRs) used in production linear low-density polyethylene (LLDPE). However, studies reporting on practical industrial control engineering such relying equilibrium mechanisms are scarce. This study presents a thorough analysis hot thermoregulating water (TRW) valve-jamming incident and interprets related phenomena parameter changes. effect catalyst activity variations liquid-phase quantities TRW valve action investigated depth, general explanation provided by analyzing typical distributed system data trends proven deductive reasoning. Results indicate that polymerization maintained two pathways. first pathway to latent (condensate)/sensible heat (gas) extraction materials, second associated with system, specifically cold branches. These pathways exhibited synergistic bidirectional effects. Finally, series innovative measures proposed internal external operations fully prevent respond malfunctions maintain overall stability. enhances dependability through advanced process optimization utilizing Unipol prototype offers perspectives processes.

Language: Английский

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Facile approach towards terminal olefins from esters using Corey-Chaykovsky’s reagents

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: 22(25), P. 5093 - 5096

Published: Jan. 1, 2024

A new synthetic method for terminal olefins was developed through the reaction of Corey–Chaykovsky reagent with readily available esters. mechanism involving nucleophilic addition, elimination and rearrangement is supported by DFT calculations.

Language: Английский

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Ammonium Tetrakis(pentafluorophenyl)borate: Preparation and Application in Olefin Coordination Polymerization as the Cocatalyst Compound

Polymers, Journal Year: 2024, Volume and Issue: 16(12), P. 1689 - 1689

Published: June 13, 2024

Metallocene catalysts have attracted much attention from academia and industry for their excellent catalytic activity in the field of olefin polymerization. Cocatalysts play a key role metallocene systems, which can not only affect overall activity, but also an obvious influence on structure properties polymer. Although methylaluminoxane (MAO) is currently most widely used cocatalyst, its price increases production cost polyolefin materials. Ammonium tetrakis(pentafluorophenyl)borate has shown performance polymerization, being one best substitutes traditional cocatalyst MAO. Compared with main catalyst, whose composition are relatively complex, research very limited. This review mainly introduces history, preparation methods, application progress polymerization ammonium tetrakis(pentafluorophenyl)borate, deepening our understanding hope inspiring brand-new thinking improving enhancing catalyst systems.

Language: Английский

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Efficient synthesis of the cyclo-olefin copolymers at high temperature and pressure in a homogeneous mini-tubular reactor

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 497, P. 154602 - 154602

Published: Aug. 9, 2024

Language: Английский

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Theoretical Study on the High Polymer Molecular Weight of Heteroatom-Substituted Constrained Geometry Catalyst

Polymers, Journal Year: 2024, Volume and Issue: 16(23), P. 3251 - 3251

Published: Nov. 22, 2024

This theoretical study investigates the high molecular weight (Mw) production in copolymerization of ethylene and 1-octene using heteroatom-substituted constrained geometry catalysts (CGCs). The research explores correlation between chain termination reactions polymer weight, revealing that Gibbs free energy barrier is positively linked to weight. Quantitative structure-property relationship models were constructed, indicating descriptors such as atom charge, orbital energy, buried volume significantly influence

Language: Английский

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Gradient Ethylene/α-Olefin Copolymer Prepared via In Situ Copolymerization

Macromolecules, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 26, 2024

Synthesis of gradient copolymers through coordination insertion copolymerization is an unmet goal since the prerequisite not only being performed in a living manner but also composition drift sensitive to change comonomer concentration. Herein, these challenging issues ethylene/1-hexene polymerization were simultaneously solved by carefully tuning steric ortho-substituent amine bis(phenolate) moiety within corresponding titanium complex. The complex 1 catalyzed give P1–P4 certain range 1-hexene concentrations situ and block copolymer P5 sequential feeding strategy. structure–property relationship between phase structure mechanical property electric breakdown voltage elucidated. Compared P4 containing tiny crystalline phase, P3 with large discrete shows much higher (209.6 kV/mm vs 146.6 kV/mm) tensile strength (23.6 MPa 3.8 MPa). With accumulation P2, slightly decreases 199.7 kV/mm, improves 34.0 MPa, which are similar those (Eb = 183.7 σb 32.8 MPa) superior P1 160.7 25.9 continuous phase.

Language: Английский

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Archie E. Hamielec memorial issue

The Canadian Journal of Chemical Engineering, Journal Year: 2023, Volume and Issue: 101(9), P. 4800 - 4803

Published: May 19, 2023

Data sharing is not applicable to this article as no new data were created or analyzed in study.

Language: Английский

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