This study presents a novel polyurethane-activated carbon composite (PACC) as an effective and sustainable adsorbent for treating lead-ion-contaminated waters. The PACC was characterized using Scanning Electron Microscopy with Energy Dispersive X-ray (SEM-EDX), Fourier Transform Infrared Spectroscopy (FTIR), Brunauer, Emmett, and Teller (BET) surface area analyzer, X-ray Diffraction (XRD), and Thermogravimetric Analyzer (TGA) to evaluate its physicochemical and thermal properties. Furthermore, the PACC was employed in an experimental column adsorption setup to investigate its adsorption performance and to develop a dynamic method suitable for industrial implementation. Parameters such as bed height (50, 100, 150 mm), flow rate (4, 6, 8 mL min−1), pH (2, 4, 6), and initial metal-ion concentrations (10, 50, 100 mg L−1) were examined. The experimental data exhibited strong agreement with the Thomas and Yoon–Nelson models (R2 ≥ 0.96), indicating efficient adsorption mechanisms. Remarkably, the used adsorbent has the potential for facile regeneration without substantial loss in capacity. The PACC demonstrated excellent adsorption performance for lead ions in aqueous solutions in a fixed-bed column system. Thus, the novel PACC material holds the potential for scalable application in industrial settings to address water pollution challenges, especially in regions with uncontrolled effluent discharge.
Coconut oil, a low-molecular-weight vegetable oil, is virtually unutilized as a polyol material for flexible polyurethane foam (FPUF) production due to the high-molecular-weight polyol requirement of FPUFs. The saturated chemistry of coconut oil also limits its compatibility with widely used polyol-forming processes, which mostly rely on the unsaturation of vegetable oil for functionalization. Existing studies have only exploited this resource in producing low-molecular-weight polyols for rigid foam synthesis. In this present work, high-molecular-weight polyester polyols were synthesized from coconut monoglycerides (CMG), a coproduct of fatty acid production from coconut oil, via polycondensation at different mass ratios of CMG with 1:5 glycerol:phthalic anhydride. Characterization of the CMG-based polyol (CMGPOL) products showed number-average molecular weights between 1997 and 4275 g/mol, OH numbers between 77 and 142 mg KOH/g, average functionality between 4.8 and 5.8, acid numbers between 4.49 and 23.56 mg KOH/g, and viscosities between 1.27 and 89.57 Pa·s. The polyols were used to synthesize the CMGPOL-modified PU foams (CPFs) at 20 wt % loading. The modification of the foam formulation increased the monodentate and bidentate urea groups, shown using Fourier transform infrared (FTIR) spectroscopy, that promoted microphase separation in the foam matrix, confirmed using atomic force microscopy (AFM) and differential scanning calorimetry (DSC). The implications of the structural change to foam morphology and open cell content were investigated using a scanning electron microscope (SEM) and gas pycnometer. The density of the CPFs decreased, while a significant improvement in their tensile and compressive properties was observed. Also, the CPFs exhibited different resiliency with a correlation to microphase separation. These findings offer a new sustainable polyol raw material that can be used to modify petroleum-based foam and produce flexible foams with varying properties that can be tailored to meet specific requirements.
In this research, a new method of treating wastewater is introduced using a highly recyclable and sustainable material derived from coconut oil. This material aims to address the issues commonly faced by conventional sorbents, such as limited performance and costly production. These challenges impede a sorbent material from unlocking its full utility in treating wastewater. An exceptional sorbent material was synthesized by incorporating coconut shell-based activated carbon (AC) into a coconut oil-based polyurethane matrix to produce an activated carbon-infused polyurethane (ACIP). The effective adsorption was elucidated by the synergistic interaction between the ACIP material and methylene blue (MB) through electrostatic attraction, π-π interactions, and hydrogen bonding. To provide an exhaustive analysis of the ACIP material, several analytical techniques were employed, including Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) analysis, X-ray diffraction (XRD) analysis, and thermogravimetric analysis (TGA). A detailed assessment using a fixed-bed column setup investigated its adsorption behavior by encompassing various factors such as inlet concentration, adsorbent bed height, feed flow rate, and solution pH. Results revealed that the ACIP composite exhibited a maximum adsorption capacity of 28.25 mg g−1. Empirical evidence with a high correlation coefficient (R2 > 0.93) obtained from the Thomas and Yoon–Nelson model suggests the suitability of the composite material to operate efficiently under these diverse circumstances. Notably, after five consecutive adsorption–desorption cycles, ACIP demonstrated its remarkable reusability by maintaining 86% of its regeneration efficiency. Given its outstanding performance and potential for scalability, this innovative ACIP composite presents a more sustainable approach to addressing wastewater issues within industrial environments.
The increasing focus on sustainable construction is driving the industry toward materials that combine functionality with environmental benefits. A viable approach to address this demand is the use of bio-based additives to improve traditional cementitious composites. This study introduces a novel approach to developing a polymer-modified construction material by incorporating varied amounts (0, 1, 2, 3, and 6%) of bio-based polyurethane (PU), derived from polyglycerol polyester polyol, into cementitious mortar. The resulting PU-modified cementitious mortar (PUMC) was evaluated for its mechanical, physicochemical, and microstructural properties. Results show that the incorporation of 2% PU by cement weight significantly enhanced compressive strength by 58.2%, flexural strength by 37.0%, and initial flow performance by 20.0% after 28 days, while a 6% PU incorporation provided the best abrasion resistance. These improvements were attributed to a uniform particle and pore size distribution and the formation of a uniform interpenetrating polymer network (IPN), as confirmed by BET-BJH and SEM-EDX analyses. Additionally, FTIR and TGA analyses revealed that the metal-ligand coordination between Ca2+ ions in the cement mortar and PU ligand groups strengthened the interfacial connectivity through noncovalent bonding, further enhancing the material properties. This research highlights the potential of bio-based PU as an eco-friendly additive that significantly improves the performance of cementitious mortars, making it a promising option for industrial flooring applications.
Marine oil spills have caused significant environmental problems. Among the array of clean-up methods, the utilization of sorbents emerges as promising for removing and recovering oil from spills. Developing cost-effective, reliable, and eco-friendly material that efficiently and sustainably removes oil from water is increasingly seen as crucial and pressing. In the present study, we report the development of coco-polyurethane (PU) foam (CCF) through the conventional foaming process using varying amounts of coconut-oil-derived polyol (CODP) in a PU matrix. Characterization of the foams showed an increased ester band with the incorporation of COPD into the polyurethane networks and no direct influence of the cell size distribution on the surface morphology. Furthermore, this study highlighted the increasing CODP in every CCF formulation, showing high oil sorption and low water uptake due to its porous structure. The experimental results revealed that CCF is a potential candidate sorbent for the recovery of spilled oil. This signifies a significant leap towards reducing the dependency on petroleum in developing sorbent materials and advancing sustainable responses to oil spills in marine environments.