Bio-mordants: a review

Due to the increasing pressure on environmentally friendly approaches and sustainable production processes, the textile dyeing industry has focused on natural colorants. Thus, the use of bio-mordants, which are biological materials, has become widespread as an alternative to metal salts, most of which are non-ecological, used in the application processes of natural colorants. In natural dyeing, dyers want to use mordant substances in the dyeing processes in order to both expand the color spectrum and improve the fastness properties. Conventional metal salts used in natural dyeing are made up of metallic ions, which, when released into the environment as wastewater effluent at the end of the dyeing process, cause major damage to the ecosystem. Many researchers have thought about using mordants derived from natural sources to address the environmental problem. This article is a review of the investigation of natural mordants used instead of metallic mordants in the process of coloring various textile materials with natural dyestuff sources. It has been determined that many substances, most of them herbal materials, are used as mordants. In this review, mordants, except for conventional metal salts, are examined under three main groups for a better understanding. These groups are as follows: (i) natural or bio-mordants, (ii) oil mordants, and (iii) new-generation and non-vegetable-based mordants. Here, researchers will find an overview of the most recent developments in green mordants as well as application techniques for a variety of mordants.

Green financing and technological innovation influence on e-commerce industry green environment

The urgent need to address environmental concerns has led to the adoption of green production targets by businesses worldwide. This paper explores the influence of green financing and technological innovation on green e-commerce as companies seek to achieve these targets. The study uses a qualitative research design, employing semi-structured interviews with industry experts to gather data. The findings indicate that green financing has a significant positive effect on adopting green production practices and implementing green technological innovations, positively impacting green e-commerce. To reduce emissions of greenhouse gases and promote long-term economic development, COP 26's guiding principles emphasize the need for robust institutions and environmentally responsible technology innovation. Carbon dioxide (CO2) emissions and associated factors will be analyzed in this research for numerous South Asian nations from 1995 to 2020. Institutional and green technological improvements, alternative energy sources, more accessible commerce, population growth, and economic growth are all examples of such factors. With the possibility of residual cross-sectional dependency and heterogeneity, the research used second-generation panel methodologies to investigate the interrelationships between the variables. Switching to renewable energy sources and implementing environmentally friendly technology innovations have both been shown to cut CO2 emissions by an empirically supported 0.084% and 0.054%, respectively. There is a 0.215 percentage point deterioration in environmental quality due to poor institutional quality, a growing population, increased trade openness, and a thriving economy. The study concludes that achieving green production targets depend on the availability of green financing and the adoption of green technological innovations in the e-commerce industry. This paper provides insights for policymakers, businesses, and investors interested in promoting sustainable business practices and the achievement of green production targets.

Cooperative membership and farmers' environment-friendly practices: Evidence from Fujian, China

This study investigates the relationship between Chinese farmers' propensity to adopt environment-friendly practices and their membership in cooperatives. Based on data collected in 2021 from the Fujian China Household Survey, the Endogenous Switching Probit model (ESP) is applied to account for unobserved factors that could simultaneously affect farmers' cooperative membership and their willingness to adopt environment-friendly practices. First, the results indicate that a cooperative membership has a positive impact on the level of farmers' interest in green production practices. Second, there is evidence of some heterogeneity (based on both observable and unobservable characteristics) in the impact of cooperative membership; the higher the farmers' capital returns, the more prominent the role of cooperatives in guiding these farmers. Third, participation in cooperatives is conducive to raising farmers' interest in green production. The overall conclusion is that a cooperative membership raises the Chinese farmers' willingness to adopt environment-friendly practices.

Aging, land fragmentation, and banana farmers' adoption of biopesticides in China

Encouraging farmers to adopt biopesticides is a crucial strategy for protecting the ecological environment and achieving sustainable agricultural development. This study utilizes data from a micro-survey of 454 banana farmers from Hainan Province of China and employs a logit model to analyze the effects of aging, land fragmentation, and their interactions on farmers' adoption of biopesticides, as well as the heterogeneity of farmers in different household life cycles. The findings reveal that aging and land fragmentation both hinder biopesticide adoption, with farmers experiencing higher levels of aging and more fragmented land holdings being less likely to utilize biopesticides in banana production. Mechanism analysis uncovers an interaction effect between aging and land fragmentation that hampers biopesticide adoption. Furthermore, the effects of aging, land fragmentation, and their interaction on biopesticide adoption behavior vary across farmers in different family life cycles. Specifically, aging negatively affects biopesticide adoption behavior for farmers in support households, while land fragmentation negatively influences farmers in dependency and burden households. The interaction between aging and land fragmentation adversely affects farmers in burden households. Our findings highlight the importance of aging agricultural labor and land fragmentation to promote green agriculture in China and call for more relevant policies to encourage farmers with different household life cycles to adopt biopesticides in farming practices.

Mode of innovative green production for concrete engineering: life cycle assessment of accelerators prepared from aluminum mud wastes

In this study, two types of liquid alkali-free accelerators were prepared by aluminum sulfate (AF₁) and aluminum mud wastes (AF₂), and the life cycle assessment (LCA) in the preparation of AF₁ and AF₂ was compared. The LCA was considered from cradle to gate including raw materials used, transportation, and accelerator preparation based on the method ReCiPe2016. The results indicated that AF₁ had a higher environmental impact in all midpoint impact categories and endpoint indicators than that of AF₂, and AF₂ reduced 43.59% emission of CO₂, 59.09% emission of SO₂, 71% consumption of mineral resources, and 46.67% consumption of fossil resources than that of AF₁ respectively. As an environment-friendly accelerator, AF₂ had a better application performance than traditional accelerator AF_1. When the dosage of accelerators was 7%, the initial setting times of cement pastes containing AF₁ and AF₂ were 4 min 57 s and 4 min 04 s respectively, the final setting times of cement pastes containing AF₁ and AF₂ were 11 min 49 s and 9 min 53 s respectively, and the compressive strengths at 1 d of mortars containing AF₁ and AF₂ were 7.35 MPa and 8.33 MPa respectively. This study aims to provide technical feasibility and environmental impact assessment for exploring new avenues of preparing environment-friendly liquid alkali-free accelerators with aluminum mud solid wastes. It has great potential in reducing carbon and pollution emissions and has a greater competitive advantage due to great application performance.

Synergy of directional oxidation and vacuum gasification for green recovery of As2O3 from arsenic-containing hazardous secondary resources

Arsenic, a hazardous material that is toxic for humans, enters the human body through soil, water, and air. Furthermore, metal smelting is known to produce arsenic-containing hazardous secondary resources (AHSRs), which cause irreversible damage to the total environment. Therefore, a novel, clean, and efficient arsenic fixation technology has been developed in this study for arsenic removal, which involves directional oxidation and vacuum gasification of AHSRs. Oxidation results revealed that physical phases containing arsenic (As, As₂O₃, As₂Te₃ and Cu₃As) are selectively oxidized to As₂O₃ completely and thus classified as oxidative modulation products (OMPs). Meanwhile, approximately 98.82% As₂O₃ of OMPs convert into volatiles in the following gasification. Characterization results showed that As₂O₃ with 96.72% purity and uniform microscopic distribution was obtained in the form of monoclinic crystalline needle-like crystals. The proposed approach organically combines oxidation and volatilization properties of each element to facilitate clean and efficient separation as well as recovery of As₂O₃. No hazardous gas or wastewater is discharged during the entire process, thereby ensuring that arsenic is recycled in a sustainable and clean manner. Overall, this study provides a clean and low-carbon approach for recycling secondary resources containing arsenic.

Big data analytics capabilities for reinforcing green production and sustainable firm performance: the moderating role of corporate reputation and supply chain innovativeness

The literature review lacks empirical studies on the role of big data analytics (BDA) and green technological innovation capabilities (GTICs) in promoting the sustainable performance of the manufacturing industry. The primary objective of this study is to examine the role of BDA-technology capability, GTIC, and environmental orientation toward green production and sustainable firm performance. Moreover, this research paper investigates the mediating role of green production and green competitive advantage and the moderating role of corporate reputation and supply chain innovativeness. Primary data was collected from Pakistani manufacturing firms through the survey method. Structural equation modeling was applied to measure and verify the relationship of proposed hypotheses. Empirical findings show BDA technology capability, GTIC, and environmental orientation positively contribute to green production. Moreover, green production helps achieve a green competitive advantage, and green competitive advantage positively influences sustainable firm performance. Furthermore, mediating role of green production and green competitive advantage and moderating role of corporate reputation and supply chain innovativeness was also confirmed. This study contributes by developing a comprehensive model showing the relationship between organizational capabilities, BDA technology capability, GTIC, and sustainable firm performance by considering potential mediators and moderators. Thus, this research suggests enhancing green production and sustainable firm performance through adopting BDA technology capability and GTIC by Pakistani manufacturing firms.

Cassava wastewater valorization for the production of biosurfactants: surfactin, rhamnolipids, and mannosileritritol lipids

The global production of cassava was estimated at ca. 303 million tons. Due to this high production, the cassava processing industry (cassava flour and starch) generates approximately ca. 0.65 kg of solid residue and ca. 25.3 l of wastewater per kg of fresh processed cassava root. The composition of the liquid effluent varies according to its origin; for example, the effluent from cassava flour production, when compared to the wastewater from the starch processing, presents a higher organic load (ca. 12 times) and total cyanide (ca. 29 times). It is worthy to highlight the toxicity of cassava residues regarding cyanide presence, which could generate disorders with acute or chronic symptoms in humans and animals. In this sense, the development of simple and low-cost eco-friendly methods for the proper treatment or reuse of cassava wastewater is a challenging, but promising path. Cassava wastewater is rich in macro-nutrients (proteins, starch, sugars) and micro-nutrients (iron, magnesium), enabling its use as a low-cost culture medium for biotechnological processes, such as the production of biosurfactants. These compounds are amphipathic molecules synthesized by living cells and can be widely used in industries as pharmaceutical agents, for microbial-enhanced oil recovery, among others. Amongst these biosurfactants, surfactin, rhamnolipids, and mannosileritritol lipids show remarkable properties such as antimicrobial, biodegradability, demulsifying and emulsifying capacity. However, the high production cost restricts the massive biosurfactant applications. Therefore, this study aims to present the state of the art and challenges in the production of biosurfactants using cassava wastewater as an alternative culture medium.

Cellulose I nanocrystals (CNCs I) prepared in mildly acidic lithium bromide trihydrate (MALBTH) and their application for stabilizing Pickering emulsions

This study proposed a sustainable method to prepare cellulose I nanocrystals (CNCs I) from microcrystalline cellulose (MCC) in a mildly acidic lithium bromide trihydrate (MALBTH) system, a concentrated (50 wt%) solution of LiBr in water with recyclable formic acid (FA). First, the MCC was treated in the MALBTH system to generate CNCs with a uniform size, yield higher than 68.49% and crystallinity of 84.02%. Then, the CNCs could application for stabilizing Pickering emulsions for at least 15 days. Furthermore, FA was easily recycled from the MALBTH system, and the yield of the CNCs produced from the hydrolysis of MCC by using the recycled FA was still higher than 60%. Finally, this study provided a sustainable and green production of CNCs. A low-cost and environmentally friendly pathway to recover FA from the MALLBTH system at a high yield was still realized.

Green and simple production of graphite intercalation compound used sodium bicarbonate as intercalation agent

In view of the technical difficulties in the preparation of graphite intercalation compound (GIC) such as complex processes, the need to use strong acid reagents, and the product containing corrosive elements. A novel, efficient and simple method used sodium bicarbonate as intercalation agent was developed, which combined with mechanical force and chemical method for the green production of GIC. The production parameters were optimized by the single factor experiments, the optimal conditions were the ball mill speed 500 r/min for 4 h (6 mm diameter of the stainless-steel beads as ball milling media), the decomposition temperature 200 ℃ for 4 h, and 1:1 mass ratio of flake graphite to sodium bicarbonate. SEM results revealed that the prepared product appears the lamellar separation, pores, and semi-open morphology characteristic of GIC. FT-IR results indicated that the preparation method does not change the carbon-based structure, and the sodium bicarbonate intercalant has entered the interlayer of graphite flakes to form GIC. XRD results further showed that the GIC products still maintained the structure of carbon atoms or molecules, and the sodium bicarbonate intercalation agent has entered the interlayer of the graphite, and increased the interlayer distance of the layered graphite. The expandability of GIC products was studied, and the results show that it was expandable, and the expandable volume of GIC products prepared under optimal conditions has reached 142 mL/g. The theoretical basis for large-scale production was provided by studied the mechanism of the preparation method and designed the flow chart. The method has the advantages of simple process, products free of impurities, no use of aggressive reagents, process stable, and does not pollute the environment, being favorable to mass production, and provided new preparation method and idea for two-dimensional nanomaterials with preparation technical difficulties.

A Novel Chitosanase from Penicillium oxalicum M2 for Chitooligosaccharide Production: Purification, Identification and Characterization

This study discovered a novel chitosanase from Penicillium oxalicum M2 based on a new screening strategy. An extracellular chitosanase was isolated and purified from the fermentation broth of Penicillium oxalicum M2. A 19.34-fold purification was achieved on a cation exchange column. Using sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, chitosanase was determined at approximately 42 kDa without any subunits. The sequence of peptide in the protein was identified as SALNKNYITNFSTLR by MALTI-TOF/TOF MS. The maximum catalytic activity of the purified enzyme was 60.45 U/mg at the optimum pH and temperature of 5.5 and 60 °C. The enzyme activity held stability in the range of 35-50 °C and pH 3-4.5. Ca²⁺, Mn²⁺, non-ionic surfactants (Tween 20/40/60/80 and Trition X-100) and some common reducing agents (DTT and β-ME) could significantly activate chitosanase. The purified enzyme showed rigorous specificity to chitosan as a substrate. The hydrolysate in the final stage of hydrolysis consisted of chitooligosaccharides with a degree of polymerization ranging from 2 to 5 and without glucosamine or acetylglucosamine. The monomeric enzyme obtained by one-step purification reveal applications potential in sugar industry, and expanded our understanding of the GH75 family chitosanases simultaneously.

Impact of industrial agglomeration on environmental pollution from perspective of foreign direct investment-a panel threshold analysis for Chinese provinces

In the course of China's rapid economic development, the coexistence of industrial development and dominant industrial agglomeration (AGG), along with growing environmental problems, has attracted widespread attention from scholars. Although the linear relationship between the two has been analyzed in depth in the research literature, a concomitant phenomenon, i.e., the gradual expansion in the scale of foreign direct investment (FDI), has been overlooked. By employing threshold panel regression model, this paper attempts to construct a theoretical model with embedded AGG and FDI, and incorporates other factors affecting environmental pollution (POL). For examining the mechanism of AGG on POL, we proposed a testable theoretical hypothesis, and conducted an empirical study by combining panel data of POL and AGG at the provincial level in China. The measurement index of a control variable was changed to check the robustness of our results, and the coefficient sign of each explanatory variable was not changed, confirming the robustness of main results. Overall, AGG improves regional POL, but the impact of FDI is stage-specific and roughly there are three stages. Specifically, the positive effect of AGG on POL is strong when FDI is at a low level. When the level of FDI crosses the first threshold and continues to rise, the positive effect of AGG on POL reaches its strongest; until the second threshold is crossed, the positive effect of AGG starts diminishing slowly. Concluding this, for promoting economic development and environmental protection in the region in parallel, government and enterprises should prioritize the increment in FDI, with an equalization of levels of AGG and FDI, in order to enhance the improvement effect of AGG on POL.

Is environmental management an economically sustainable business?

This paper investigates whether environmental management is an economically sustainable business. While firms invest in green production and green supply chain activities with the primary purpose of reducing their environmental impact, the reciprocal relationships with economic performance need to be clarified. Would firms and suppliers adjust their environmental strategies if the higher economic value that environmental management generates is reinvested in greening actions? We found out that environmental management positively influences economic performance as second order (long term) target, to be reached conditioned by higher environmental performance; in addition, firms can increase their performance if they reinvest the higher economic value gained through environmental management in green practices: While investing in environmental management programs is a short term strategy, economic rewards can be obtained only with some delays. Consequently, environmental management is an economically sustainable business only for patient firms. In the evaluation of these reciprocal relationships, we discovered that green supply chain initiatives are more effective and more economically sustainable than internal actions.

Utilization of food industry wastes for the production of zero-valent iron nanoparticles

The proper disposal of the several types of wastes produced in industrial activities increases production costs. As a consequence, it is common to develop strategies to reuse these wastes in the same process and in different processes or to transform them for use in other processes. This work combines the needs for new synthesis methods of nanomaterials and the reduction of production cost using wastes from citrine juice (orange, lime, lemon and mandarin) to produce a new added value product, green zero-valent iron nanoparticles that can be used in several applications, including environmental remediation. The results indicate that extracts of the tested fruit wastes (peel, albedo and pulp fractions) can be used to produce zero-valent iron nanoparticles (nZVIs). This shows that these wastes can be an added value product. The resulting nZVIs had sizes ranging from 3 up to 300 nm and distinct reactivities (pulp>peel>albedo extracts). All the studied nanoparticles did not present a significant agglomeration/settling tendency when compared to similar nanoparticles, which indicates that they remain in suspension and retain their reactivity.

Application of green zero-valent iron nanoparticles to the remediation of soils contaminated with ibuprofen

Zero-valent iron nanoparticles (nZVIs) are often used in environmental remediation. Their high surface area that is associated with their high reactivity makes them an excellent agent capable of transforming/degrading contaminants in soils and waters. Due to the recent development of green methods for the production of nZVIs, the use of this material became even more attractive. However, the knowledge of its capacity to degrade distinct types of contaminants is still scarce. The present work describes the study of the application of green nZVIs to the remediation of soils contaminated with a common anti-inflammatory drug, ibuprofen. The main objectives of this work were to produce nZVIs using extracts of grape marc, black tea and vine leaves, to verify the degradation of ibuprofen in aqueous solutions by the nZVIs, to study the remediation process of a sandy soil contaminated with ibuprofen using the nZVIs, and to compare the experiments with other common chemical oxidants. The produced nZVIs had nanometric sizes and were able to degrade ibuprofen (54 to 66% of the initial amount) in aqueous solutions. Similar remediation efficiencies were obtained in sandy soils. In this case the remediation could be enhanced (achieving degradation efficiencies above 95%) through the complementation of the process with a catalyzed nZVI Fenton-like reaction. These results indicate that this remediation technology represents a good alternative to traditional and more aggressive technologies.