As the population increases and manufacturing grows, greenhouse gas and other harmful emissions increase. Contaminated with chemicals such as dyes, pesticides, pharmaceuticals, oil, heavy metals or radionuclides, wastewater purification has become an urgent issue. Various technologies exist that can remove these contaminants from wastewater sources, but they often demand high energy and/or high cost, and in some cases produce contaminant laden sludge that requires safe disposal. The need for methods which are less capital intensive, less operationally costly and more environmentally friendly is suggested. Cellulose-based materials have emerged as promising candidates for wastewater treatment due to their renewability, low cost, biodegradability, hydrophilicity, and antimicrobial property. In this review article, we focussed on developing sustainable and biodegradable cellulose-based materials for wastewater treatment. This article deals with cellulose-based materials’ scope and their conversion into valuable products like hydrogel, aerogel, cellulose composites, and nanocellulose. The cellulose-based materials have no harmful environmental impact and are plentiful. The modified cellulose-based materials applying as membrane, adsorbent, sorbent, and beads to purify the wastewater were discussed. Finally, the challenges and future prospects of cellulose-based materials for wastewater treatment were considered, emphasizing their potential to be sustainable and eco-friendly alternatives to traditional materials used in wastewater treatment.

As the global population grows, the demand for textiles is increasing rapidly. However, this puts immense pressure on manufacturers to produce more fiber. While synthetic fibers can be produced cheaply, they have a negative impact on the environment. On the other hand, fibers from wool, sisal, fique, wood pulp (viscose), and man-made cellulose fibers (MMCFs) from cotton cannot alone meet the growing fiber demand without major stresses on land, water, and existing markets using these materials. With a greater emphasis on transparency and circular economy practices, there is a need to consider natural non-wood alternative sources for MMCFs to supplement other fiber types. However, introducing new feedstocks with different compositions may require different biomass conversion methods. Therefore, based on existing work, this review addresses the technical feasibility of various alternative feedstocks for conversion to textile-grade fibers. First, alternative feedstocks are introduced, and then conventional (dissolving pulp) and emerging (fibrillated cellulose and recycled material) conversion technologies are evaluated to help select the most suitable and promising processes for these emerging alternative sources of cellulose. It is important to note that for alternative feedstocks to be adopted on a meaningful scale, high biomass availability and proximity of conversion facilities are critical factors. In North America, soybean, wheat, rice, sorghum, and sugarcane residues are widely available and most suitable for conventional conversion through various dissolving pulp production methods (pre-hydrolysis kraft, acid sulfite, soda, SO₂-ethanol-water, and potassium hydroxide) or by emerging cellulose fibrillation methods. While dissolving pulp conversion is well-established, fibrillated cellulose methods could be beneficial from cost, efficiency, and environmental perspectives. Thus, the authors strongly encourage more work in this growing research area. However, conducting thorough cost and sustainability assessments is important to determine the best feedstock and technology combinations.

Ethyl levulinate (EL) is a key biomass-derived compounds due to its socio-economic benefits for the synthesis of commodity chemicals. Herein, we proposed an efficient one-step bamboo conversion to EL in ethanol, and a novel stepwise fractionation to purify EL and lignocellulose degradation products. A proton acid, due to its high catalytic efficiency, yielded 26.65% EL in 120 min at 200 °C. The productions of ethyl glucoside and 5-ethoxymethylfurfural were analyzed in terms of by-products formation. To the best of our knowledge, there is no single report on catalyst for one step synthesis of EL directly from bamboo, as well as a stepwise fractionation to purify EL. Due to similar physiochemical properties in each fraction, the platform molecules could broaden a new paradigm of bamboo biomass utilization for renewable energy and value-added biochemicals. In addition, glucose, ethyl glucoside, corn starch, and microcrystalline cellulose were also investigated as substrates, so that the reaction intermediates of this one-pot procedure were identified and a possible reaction mechanism was proposed.

The standard epoxy resin curing agents revealed are from unsustainable petroleum-based sources, which produce poisonous exhaust when cured. Amino acids, a bio-based epoxy curing agent with amino and carboxyl groups, are another potential curing agent. Water-soluble epoxy resins cured with lysine (Lys), glutamic acid (Glu), leucine (Leu), and serine (Ser) as amino acids were investigated. The results showed that the water-soluble epoxy resin (glycerol epoxy resins, GER) was cured with Lys and Glu after reacting. Fourier transform infrared (FT-IR) spectroscopic analysis of the GER-Lys showed that the amino and carboxyl groups of Lys primarily reacted with the epoxy groups of GER. The elongation at break of Lys-cured GER (GER-Lys) cured at 70 ℃ with a molar ratio of 1꞉0.75 was 75.32%. The fact that elongations at break of GER-Lys (79.43%) were higher than those of GER-Glu (17.33%), respectively supports the decrease of crosslinking density by the amino acid-cured GER reaction. The potential of Lys and Glu alternatives for petrochemical amines is demonstrated and provides promising opportunities for industrial application.

Low molecular aromatic compounds are detrimental to the enzymatic hydrolysis of lignocellulose. However, the specific role of their functional groups remains unclear. Here, a series of nine aromatic compounds as additives were tested to understand their effect on the hydrolysis yield of microcrystalline cellulose (MCC) and alkaline pretreated wheat straw. Based on the results, the inhibition of aldehyde groups on MCC was greater than that of carboxyl groups, whereas for the alkaline pretreated wheat straw case, the inhibitory effect of aldehyde groups was lower than that of carboxyl groups. Increased methoxyl groups of aromatic compounds reduced the inhibitory effect on enzymatic hydrolysis of both substrates. Stronger inhibition of aromatic compounds on MCC hydrolysis was detected in comparison with the alkaline pretreated wheat straw, indicating that the substrate lignin can offset the inhibition to a certain extent. Among all aromatic compounds, syringaldehyde with one aldehyde group and two methoxyl groups improved the glucan conversion of the alkaline pretreated wheat straw.

Large quantities of hemp hulls can be completely utilized for creation of value-added products (cost effective biofuels and biochemicals) through a biorefinery approach. A sustainable approach in making xylose, a low calorie sweetener and high surface area activated carbons (AC) for super capacitors, attracts interest. The AC when leveraged as a co-product from biorefinery process makes it more cost effective and, in this paper, we discuss the production of xylose and AC from hemp seed hull with methane sulphonic acid (MSA) hydrolysis. Xylose recovery with MSA hydrolysis was 25.15 g/L when compared to the traditional sulphuric acid (SA) hydrolysis of 19.96 g/L at the same acid loading of 1.8%. The scanning electron microscope (SEM) images and Fourier transform infrared (FT-IR) spectra indicate partial delignification along with hemicellulose hydrolysis responsible for high xylose recovery. Post hydrolysis fibers were KOH activated and carbonized to make AC. The MSA hydrolyzed and KOH activated fiber produced pure, fluffier and finer particle AC with a drastic increase in surface area 1 452 m²/g when compared to SA hydrolyzed of 977 m²/g. These results indicate the potential of MSA in dilute acid hydrolysis of biomass for xylose recovery and production of high surface area activated carbon. From a production standpoint this can lead to increased use of sustainable low-cost agricultural biomass for making high surface area AC as components in supercapacitors.