Mixed plastics waste valorization to high-added value products via thermally induced phase separation and spin-casting

Plastic waste is an underutilized resource that has the potential to be transformed into value-added materials.However,its chemical diversity leads to cost-intensive sorting techniques,limiting recycling and upcycling opportunities.Herein,we report an open-loop recycling method to produce graded feedstock from mixed polyolefins waste,which makes up 60%of total plastic waste.The method uses heat flow scanning to quantify the composition of plastic waste and resolves its compatibility through controlled dissolution.The resulting feedstock is then used to synthesize blended pellets,porous sorbents,and superhydrophobic coatings via thermally induced phase separation and spin-casting.The hybrid approach broadens the opportunities for reusing plastic waste,which is a step towards creating a more circular economy and better waste management practices.

β-Glucans: Characterization, Extraction Methods, and Valorization

β-glucans are bioactive compounds with a wide range of biological properties, including anticancer, anti-inflammatory, antioxidant, and immune-modulating properties. Due to their specific physical properties, such as (in)solubility, viscosity, and gelation, β-glucans are increasingly being used in the food, pharmaceutical, and cosmetic industries. The purpose of this review is to provide an overview of the different types of β-glucans, their sources, especially Saccharomyces cerevisiae yeasts, and the methods of extraction, isolation, and purification of β-glucans, with the aim of optimizing these methods for the efficient production process. Moreover, the physico-chemical properties, modifications, current applications and future prospects of the use of β-glucans in food, medicines, cosmetics and other potential value-added products are summarized. The data presented indicate that β-glucans will play an increasingly important role in the sector of special-purpose food products as well as in other current and future areas.

Potential Applications of Milk Fractions and Valorization of Dairy By-Products: A Review of the State-of-the-Art Available Data, Outlining the Innovation Potential from a Bigger Data Standpoint

The unique composition of milk makes this basic foodstuff into an exceptional raw material for the production of new ingredients with desired properties and diverse applications in the food industry. The fractionation of milk is the key in the development of those ingredients and products;hence continuous research and development on this field, especially various levels of fractionation and separation by filtration, have been carried out. This review focuses on the production of milk fractions as well as their particular properties, applications and processes that increase their exploitation. Whey proteins and caseins from the protein fraction are excellent emulsifiers and protein supplements. Besides, they can be chemically or enzymatically modified to obtain bioactive peptides with numerous functional and nutritional properties. In this context, valorization techniques of cheese-whey proteins, by-product of dairy industry that constitutes both economic and environmental problems, are being developed. Phospholipids from the milk fat fraction are powerful emulsifiers and also have exclusive nutraceutical properties. In addition, enzyme modification of milk phospholipids makes it possible to tailor emulsifiers with particular properties. However, several aspects remain to be overcome;those refer to a deeper understanding of the healthy, functional and nutritional properties of these new ingredients that might be barriers for its use and acceptability. Additionally, in this review, alternative applications of milk constituents in the non-food area such as in the manufacture of plastic materials and textile fibers are also introduced. The unmet needs, the cross-fertilization in between various protein domains,the carbon footprint requirements, the environmental necessities, the health and wellness new demand, etc., are dominant factors in the search for innovation approaches;these factors are also outlining the further innovation potential deriving from those “apparent” constrains obliging science and technology to take them into account.

Valorization of mining waste and tailings through paste backfilling solution, Imiter operation, Morocco

Mine waste and process tailings storage is one of important challenge for which mining operations are increasingly confronted. Treatment discharges of plants and main part of waste rock development are generally stored on surface areas. The volume and chemical characteristics of these materials generate serious problem for required storage spaces and mainly environmental degradation. Paste backfill(PBF) is one of ingenious solutions to minimize the quantity of tailings to store. PBF is basically defined as a combination of mine processing tailings, binder, and water mixing. The purpose of this paper is to present backfilling components characterization and formula verification for a waste valorization solution through paste backfilling technology in Imiter operation. Obtained results and realized analysis demonstrate PBF conformity and adequacy with assigned underground functions. However the studied recipe can be more ameliorated to obtain an optimal mixture ensuring the required mechanical strength.

Lignin valorization toward value-added chemicals and fuels via electrocatalysis:A perspective

Developing efficient approaches for lignin upgrading is of interest for the industrial production of chemicals and fuels from renewable biomass.Electrocatalytic lignin upgrading powered by renewable electricity operating under gentle conditions(at or near ambient pressures and temperatures)enables a decentralized production of chemicals and fuels.Herein,we will cover the structures of lignin and review the recent advances in the electrocatalytic lignin upgrade,the electrocatalytic depolymerization of lignin,and the electrocatalytic upgrading of lignin monomers to value-added chemicals and fuels.Finally,we provide insights into the main challenges and future perspectives of this field.

Differential metabolome landscape of Kadsura coccinea fruit tissues and potential valorization of the peel and seed tissues

Kadsura coccinea(Lem.)is a woody wine plant with a peculiar fruit enriched in important health-promoting compounds.The non-editable part of the fruit,i.e.,the seed and peel,represents more than 60%of the fruit and is considered a biowaste.This significantly restricts the development of the K.coccinea fruit industry.Clarifying the metabolic components of the different fruit parts can help to improve the utilization rate and valorization of K.coccinea.Herein,we evaluated K.coccinea fruit peel,pulp,and seed using widely-targeted metabolomics and quantified a set of 736 bioactive compounds from 11 major metabolite classes.The most prominent metabolite classes included lipids,amino acids,flavonoids,and lignans.Furthermore,our results emphasized a significant accumulation of flavonoids in pulp tissues,while alkaloids and lignans were abundant in peel and seed tissues,respectively.A total of 183 metabolites were differentially accumulated among the three tissues.Procyanidin C2,rutinoside,2-hydroxyoleanolic acid,5-hydroxymethyluracil,nootkatol,isoquercitrin,isohyperoside,quercetin-7-O-glucoside,hyperin,and rutin showed elevated accumulation in the peel.In the seed,kadsuralignan G,kadcoccilactone A,kadsuralignan H,lysoPE 20:5,iso-schisandrin ethyl alcohol,and kadangustin were significantly enriched.Our results highlight the diverse metabolome composition of K.coccinea fruit parts,which can be further exploited for its valorization in various industries.

Valorization of Solid Waste Recovery in an Institution of Higher Education

One of the biggest challenges for organizations, cities and countries is waste management. Currently, 1.3 million tons of solid wastes are generated in the cities and by 2025 it is estimated that this volume will increase up to 2.2 billion tons. Considering this, it is clear that strategies for the reduction of waste generation are needed. In order to achieve this arduous and critic task changes in education, culture and public policy are required and one of the strategies that emerge as one of the most effective is the “zero waste” programs. This paper shows the foundation of a zero waste program based on previous and successful experiences in institutions of higher education. It presents the characterization and quantification of waste, as well as the valorization of it and potential environmental and economic benefits of the implementation of this kind of programs in higher education institutions. Results show that reduction and valorization of waste generation is possible in academic sectors while other outcomes emerge, such as the generation of human capital for the implementation of this kind of programs in different sectors of society and, in that way, contribute in the transition towards sustainable development.

Physicochemical Characterization and Valorization of Clay from Lobo and Ngoya in Cameroon Central Region

Two samples clayed materials, LO and NG from central region in Cameroon were characterized for their valorization in the manufacture of refractory bricks and ceramics. In order to assess the technological properties of these clays, cooking tests were carried out on the test specimens at different temperatures. From particle size analysis, clayed materials studied have a spreading particle size and their plasticity index is between 18 and 47. The mineralogical study reveals the presence of Quartz, illite, kaolin, hematite and feldspars. High level of silica content explains the sandy nature of these clays. Linear shrinkage and density increase with temperature while compressive strength decreases with temperature. Analyses performed on the ceramic specimens after firing show that clay materials studied are suitable for the manufacture of refractory bricks.

Project for Residues Valorisation and Reutilization from an Oxy-Combustion Circulating Fluidized Bed Boiler with CO₂Capture

Power generation industry has tackled waste reuse and valorisation for decades. Nevertheless, new technologies, like Circulating fluidized bed (CFB) boilers operating in oxy-combustion, have an important gap of knowledge in residues characterization and valorisation. This project will tackle this. Furthermore, as a result of the high quantity of waste that these installations generate new business models can be opened. The project aims at characterizing the residues from a large scale oxy-CFB facility with carbon, capture, use and storage (CCUS) focusing on the larger and main residues produced: fly ash, bottom ash, and algae production from captured CO2. An analysis of possible uses and treatment needs, such as additives or preparation for use in agriculture or industry, will be carried out. Best re-utilization and valorisation options will be stated for fly ash, bottom ash and algae, aiming for a novel combination of CO2 capture technologies with recovery of valuable materials from different wastes, addressing different and sustainable solutions for their reuse, enhancing the feasibility of CCUS, and combining research with the creation of new business models towards a green economy more attractive to the public perception.

Valorization of Cucurbita pepo Seed Oil in Soap Production

The present study was conducted with the aim of extracting and characterising Cucurbita pepo seed oil and then producing soap with important dermatological properties. The physico-chemical results of the Cucurbita pepo seed oil after extraction were satisfactory and indicate that the oil obtained contains long-carbonaceous fatty acids. The production of the soap was based on the realisation of a saponification reaction by reflux heating between the extracted oil and a solution of soduim hydroxyde 7M for one hour. The soap obtained is characterised by the following physico-chemical parameters: salt content, alkali content, pH, and humidity;which meet ISO 684-1974 standards. The antibacterial parameters of the soaps S1, S2, S3, S4, S5 and S6 were determined by the Agar Diffusion test using the well method and these soaps showed an interesting antibacterial activity against the germs pseudomonas aeruginosa and staphylococcus aureus. Soaps based on Raffia sese oil (kolo oil) and Elaesis guineensis oil (palm oil) have also been synthesized for comparison with soap obtained from Cucurbita pepo seed oil.

Evaluation of the Anti-nutritional Substances in the Fruit of Gleditsia triacanthos L.： Economic Interest and Perspectives of Valorization in Algeria

Honey locust （Gleditsia triacanthos L.）, also called sweet-locust or thorny-locust, is a moderately fast growing tree. It is widely planted for windbreaks and soil erosion control and largely recommended like food of cattle since it can provide a source of fodder, protein and metabolic energy. Its flowers are incredibly attractive for pollinating insects and thus, form a source of pollen and nectar for honey. This tree was introduced in Europe in 1700 and was introduced by the colonists into Algeria in 1949. In order to valorize the natural substances of this species, the evaluation of the composition of its fruits （pods and seeds separately） in polyphenols, condensed tannins and hydrolysable tannins, which considered as anti-nutritional substances has been done. The obtained results showed that the fruits of Gleditsia triacanthos L. contain very low values in anti-nutritional factors with （0.13%-0.03%） of condensed tannins, （0.78%-0.45%） of hydrolysable tannins and （0.44%-0.16%） of total phenols for pods and seeds, respectively. It arises that these fruits can be of a great interest for many industries especially for feedstock.

Valorisation of Auriferous Indices: Case of the Siribaya Deposit, Western Mali

The purpose of this paper is to understand the valorization of gold showings in the Seribaya deposit, western Mali. Samples taken from Air Core (AC) boreholes were subjected respectively to the magnetic susceptibility test and the X-ray fluorescence analysis. These results lead to the development of a simple methodology, based on signatures/indicators geochemical to identify lithology or to locate mineralization. We note that, compared to other chemical elements, Arsenic remains the most correlated with gold in the study area. Since this correlation remains weak (r = 0.16), it shows that Arsenic does not always accompany gold. There would be a generation of Arsenic related to mineralization, and other generations that would not be. The observation of the strip logs led to the identification of the lithologies (focusing on the immobile elements, Ti, V, Cr, Y, Zr) and the establishment of the alteration profile. Highly altered levels (Saprolite ± Saprock) are characterized by the disappearance of most mobile elements. A medium to strong correlation between gold mineralization and magnetic susceptibility measurements has been observed, in some places, and at depths. These mineralized intervals typically consist of quartz veins, suggesting that they have structural control over the mineralization. Gold mineralization is believed to be related to quartz veins. In addition, gold would be in paragenesis with a generation of Arsenic hosted in coarse sediments.

Gas Valorization in the Republic of Congo: Production of Electricity from National Gas Reserves

The environmental impact of greenhouse gases based on natural gas flaring influences the rate of gas recovery around the world. In the Republic of Congo, the natural gas reserve in 2019 is estimated at 90 billion cubic meters (BCM). In this study, from the Congolese gas reserve we used five gas turbines with a capacity of 150 MW each;these five turbines consume 1.69 billion cubic meters (BCM)/year for the power of 273.750 MW and consumption of 6.57 billion kilowatt-hours. The results of this study revealed that an investment capital of 192,305,137 euros was required with a net profit of 9,581,250 euros at an annual rate of return of 4.98% with an investment payback period of approximately 20 years. This will allow the Congolese government to accomplish its policy of valuing gas and developing the country;the electricity produced by the National Petroleum Company of Congo (SNPC) will be sold to the Electrical Energy of Congo (E2C) at 0.06 euro/kWh.

Valorization of Natural Residue into Activated Carbon:Example of the Shells of the African Baobab Fruit(Adansonia digitata)L.

This study deals with the valorization of natural residues into activated carbon prepared from waste“Baobab fruit shell”from the Fatick Region,Senegal.Thus,after the preparation of the baobab shell,a chemical activation with orthophosphoric acid H3PO4(85%)was performed followed by pyrolysis at 530°C.To eliminate possible carbonization residues,the activated carbons were impregnated in 0.1 M hydrochloric acid and/or soda solutions and then washed thoroughly with distilled water to obtain a pH between 6.5 and 7.The latter were then dried in an oven at 105°C for 24 h.A characterization was carried out to determine the moisture content,the ash content,the iodine and methylene blue indices,the surface functions and the pH at zero charge point(pHpzc).The moisture and ash contents were 1.87%and 0.72%,respectively.The iodine and peroxide indices obtained were 939,09 mg/g and 575.73 mg/g,respectively.Surface function analysis by Boehm’s method showed that the acidic functions were higher than the basic functions and their pHpzc was lower than neutrality.The best efficiency of methylene blue removal was 99.75%and was obtained with a mass of 0.150 g of activated carbon,pH equal to 10,an initial concentration of methylene blue of 200 mg/L and a contact time of 35 min.

Beneficial use of mussel shell as a bioadditive for TPU green composites by the valorization of an aqueous waste

Scientific studies have focused on environmentally friendly solutions as effective as the reuse of crop products owing to plastic-waste problems in recent years.This issue is the main driving force for upcoming academic research attempts in waste valorization-related studies.Herein,we integrated an aqua-waste,mussel shell(MS),as a bioadditive form into green thermoplastic polyurethane(TPU)green composites.Tuning of the MS surface was performed to achieve strong adhesion between composite phases.The surface functionalities of MS powders were evaluated via infrared spectroscopy and scanning electron microscopy(SEM)images.Composite samples were prepared by melt-compounding followed by injection molding techniques.It was confirmed by morphological analysis that relatively better adhesion between the phases was achieved for composites involving surface-modified MS compared to unmodified MS.Tensile strength and Young’s modulus of surface-modified MS-filled composites were found to be higher than those of unmodified MS,whereas the elongation at break shifted to lower values with MS inclusions.The shore hardness of TPU was remarkably improved after being incorporated with silane-treated MS(AS-MS).Stearic acid-treated MS(ST-MS)additions resulted in an enhancement in the thermal stability of the composites.Thermo-mechanical analysis showed that the storage moduli of composites were higher than those of unfilled TPU.ST-MS additions led to an increase in the characteristic glass transition temperature of TPU.Melt flow index(MFI)of neat TPU was highly improved after MS loading regardless of modification type.According to the wear test,surface modification of MS displayed a positive effect on the wear resistance of TPU.As the water absorption data of the composites were evaluated,the TPU/AS-MS composite yielded the lowest water absorption.The silane layer on MS inclusion promoted water repellency of composites due to the hydrophobicity of silane.The results of the biodegradation investigation demonstrated that adding unmodified and/or modified MS to the TPU matrix increased the biodegradation rate.The test results at the end of a 7-week period of biodegradation with a soft-rot fungus implied that the composite materials were more biodegradable than pure TPU.Silane modification of MS exhibited better performance in terms of the characterized properties of TPU-based composites.

Recent advances in carbon dioxide selective hydrogenation and biomass valorization via single-atom catalysts

The utilization of fossil fuels has brought unprecedented prosperity and development to human society,but also caused environmental pollution and global warming triggered by excess greenhouse gases emission.For one thing,the excess emission of carbon dioxide(CO_(2)),which has a negative impact on global temperature and ocean acidity,needs to be controlled.For another,the depletion of fossil fuels will eventually force people to seek alternative carbon sources to maintain a sustainable economy.Thus,using renewable energy to convert CO_(2) and biomass into value-added chemicals and fuels is a promising method to overcome urgent problems.The hy-drogenation of CO_(2) is very important to mitigate the greenhouse effect caused by CO_(2),while biomass conversion can produce alternative renewable biofuels and green chemicals.As a kind of promising catalyst,heterogeneous single-atom catalyst(SAC)has received extensive attention in the past decades.SACs combine the advantages of homogeneous catalysts with uniform active sites and heterogeneous catalysts that are easily separable.In this review,we will give a comprehensive overview of the latest progress in CO_(2) selective hydrogenation and biomass conversion via SACs.

Electrochemical valorization of lignin:Status,challenges,and prospects

As the second most abundant component of lignocellulosic biomass and the largest source of renewable aromatic compounds,lignin shows great potential to replace finite,non-renewable fossil oils and becomes a renewable feedstock for the production of fuel and aromatic chemicals.Therefore,it is highly important to develop efficient methods to convert lignin into biofuels and valuable chemicals.Electrochemical approaches are considered to be scalable,oxidant/reductant free,easy to control,and can be conducted under mild conditions.This review firstly overviews the structure and deconstruction methods of lignin.And then,different electrochemical lignin conversion approaches,including mediated electrooxidation,electroenzymatic oxidation,photo-electrochemical oxidation,and direct electrooxidation,are discussed in detail.The application of lignin-derived monomeric compounds is also briefly introduced.Finally,the advantages and challenges of different electrochemical lignin upgrading approaches are summarized;meanwhile,suggestions are made for future research on lignin biomass valorization.

秸秆废物高值转化5-羟甲基糠醛的研究动态分析

废弃秸秆产量大,以秸秆类生物质废物制备5-羟甲基糠醛(5-hydroxymethylfurfural, HMF),是绿色安全资源化处理处置的途径之一,可有效缓解固废处置、可再生能源发展和环境的压力,为国家战略储备提供新思路。为了解秸秆废物高值转化HMF的研究热点与发展趋势,借助文献计量方式进行归纳总结,利用VOSviewer和CiteSpace软件对关键词进行可视化分析。结果显示:近20 a,国内外研究热点主要聚焦于秸秆废物的预处理、生物质高值转化HMF的核心技术以及制备HMF的潜力提升策略等方面。然而,该领域发展过程中仍存在HMF产率低、预处理成本大、分离提纯困难和产业化困难等问题,还有待进一步的开发和探索。根据对研究主题发展脉络和突现词分析,推测制备液体燃料、精细化学品等可能是秸秆废物高值转化HMF的发展方向,可为秸秆废物高效高值利用提供科学支撑。

P-induced electron transfer interaction for enhanced selective hydrogenation rearrangement of furfural to cyclopentanone

Optimizing the intrinsic activity of non-noble metal by precisely tailoring electronic structure offers an appealing way to construct cost-effective catalysts for selective biomass valorization.Herein,we reported a P-doping bifunctional catalyst(Ni-P/mSiO_(2))that achieved 96.6%yield for the hydrogenation rearrangement of furfural to cyclopentanone at mild conditions(1 MPaH_(2),150°C).The turnover frequency of Ni-P/mSiO_(2)was 411.9 h^(-1),which was 3.2-fold than that of Ni/mSiO_(2)(127.2 h^(-1)).Detailed characterizations and differential charge density calculations revealed that the electron-deficient Niδ+species were generated by the electron transfer from Ni to P,which promoted the ring rearrangement reaction.Density functional theory calculations illustrated that the presence of P atoms endowed furfural tilted adsorb on the Ni surface by the C=O group and facilitated the desorption of cyclopentanone.This work unraveled the connection between the localized electronic structures and the catalytic properties,so as to provide a promising reference for designing advanced catalysts for biomass valorization.

Advancements in transition bimetal catalysts for electrochemical 5-hydroxymethylfurfural(HMF) oxidation

The electrochemical oxidation of 5-hydroxymethylfurfural(HMF) represents a significant avenue for sustainable chemical synthesis, owing to its potential to generate high-value derivatives from biomass feedstocks. Transition metal catalysts offer a cost-effective alternative to precious metals for catalyzing HMF oxidation, with transition bimetallic catalysts emerging as particularly promising candidates. In this review, we delve into the intricate reaction pathways and electrochemical mechanisms underlying HMF oxidation, emphasizing the pivotal role of transition bimetallic catalysts in enhancing catalytic efficiency. Subsequently, various types of transition bimetallic catalysts are explored, detailing their synthesis methods and structural modulation strategies. By elucidating the mechanisms behind catalyst modification and performance enhancement, this review sets the stage for upcoming advancements in the field, ultimately advancing the electrochemical HMF conversion and facilitating the transition towards sustainable chemical production.