Processes

Journal Browser

► Journal Browser

Emerging Technologies in Solid Waste Recycling and Reuse

Share This Special Issue

Special Issue Editors

Special Issue Information

Dear Colleagues,

With the increasing global population and industrial expansion, waste generation has become a critical environmental and economic challenge. Traditional disposal methods, such as landfilling and incineration, are being reconsidered due to their environmental impacts, prompting the need for innovative recycling and reuse technologies. Advances in material recovery, waste-to-energy conversion, and circular economy principles have opened new pathways for sustainable waste management.

The integration of digital tools, artificial intelligence, and automation in waste sorting and processing is further revolutionizing the sector, enhancing efficiency and reducing environmental footprints.

This Special Issue seeks high-quality research contributions focusing on innovative solutions for waste minimization, resource recovery, and sustainable reuse. We would also highly appreciate literature reviews and state-of-the-art articles.

Topics of interest include, but are not limited to, the following:

Novel recycling processes, biodegradable and recyclable materials;
Waste valorization strategies;
Effluent purification processes using waste;
Development of new materials through the use of waste;
Smart waste management systems;
Life cycle assessment (LCA) of recycling technologies;
Policy frameworks supporting circular economy initiatives;
Contributions exploring the role of Industry 4.0 technologies, such as IoT, machine learning, and robotics, in optimizing waste recycling and reuse processes;
Circular economy in waste management.

Thank you, and I hope you consider participating in this Special Issue.

Sincerely,

Prof. Dr. Ruan L. S. Ferreira
Dr. Cinthia Maia Pederneiras
Dr. Saraiva Pereira Jéssyca Emanuella
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Processes is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Benefits of Publishing in a Special Issue

Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.

Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.

Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.

External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.

Reprint: MDPI Books provides the opportunity to republish successful Special Issues in book format, both online and in print.

Further information on MDPI's Special Issue policies can be found here.

Published Papers (1 paper)

Order results

Result details

Show export options Show export options

Select all

Export citation of selected articles as:

Research

14 pages, 1557 KiB

Open AccessArticle

Lignin Extracted from Green Coconut Waste Impregnated with Sodium Octanoate for Removal of Cu²⁺ in Aqueous Solution

by Jéssyca E. S. Pereira, Eduardo L. Barros Neto, Lindemberg J. N. Duarte, Ruan L. S. Ferreira, Ricardo P. F. Melo and Paula F. P. Nascimento

Processes 2025, 13(5), 1590; https://doi.org/10.3390/pr13051590 - 20 May 2025

Viewed by 525

Abstract

Investigating viable processes for the use of lignocellulosic biomass in clean fuels and high-value-added chemical products is essential for sustainable development. Large amounts of lignin are available every year as by-products of the paper and biorefinery industries, causing a series of problems, particularly environmental ones. Its structure and composition make lignin compatible with the concept of sustainability, since it can be used to produce new chemical products with high added value. As such, this study aims to extract lignin from green coconut fiber (LIG), with the subsequent impregnation of a sodium-octanoate-based surfactant (LIG-SUR), and determine its applicability as an adsorbent for removing copper ions from synthetic waste. To this end, the green coconut fiber lignocellulosic biomass was initially subjected to alkaline pre-treatment with 2% (w/v) sodium hydroxide in an autoclave. Next, the surface of the lignin was modified by impregnating it with sodium octanoate, synthesized from the reaction of octanoic acid and NaOH. The physical and chemical traits of the lignin were studied before and after surfactant impregnation, as well as after copper ion adsorption. The lignin was analyzed by X-ray fluorescence (XRF), Fourier transform infrared (FTIR) and scanning electron microscopy (SEM). The adsorption tests were carried out using lignin pre-treated with surfactant in a batch system, where the effects of pH and adsorbent concentration were investigated. XRF and SEM analyses confirmed surfactant impregnation, with Na₂O partially replaced by CuO after Cu²⁺ adsorption. FTIR analysis revealed shifts in O–H, C–H, C=O, and C=C bands, indicating electrostatic interactions with lignin. Adsorption kinetics followed the pseudo-second-order model, suggesting chemisorption, with equilibrium reached in approximately 10 and 60 min for LIG-SUR and LIG, respectively. The Langmuir model best described the isotherm data, indicating monolayer adsorption. LIG-SUR removed 91.57% of Cu²⁺ and reached a maximum capacity of 30.7 mg·g⁻¹ at 25 °C and a pH of 6. The results of this research showed that pre-treatment with NaOH, followed by impregnation with surfactant, significantly increased the adsorption capacity of copper ions in solution. This technique is a viable and sustainable alternative to the traditional adsorbents used to treat liquid waste. In addition, by using green coconut fiber lignin more efficiently, the research contributes to adding value to this material and strengthening practices in line with the circular economy and environmental preservation. Full article

(This article belongs to the Special Issue Emerging Technologies in Solid Waste Recycling and Reuse)

► Show Figures

Journal Menu

Journal Browser

Emerging Technologies in Solid Waste Recycling and Reuse

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Benefits of Publishing in a Special Issue

Published Papers (1 paper)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI