Extraction of Microfibrillar Cellulose From Waste Paper by NaOH/Urethane Aqueous System and Its Utility in Removal of Lead from Contaminated Water

Abstract

Though recycling of waste paper is widely practiced but usually it is downgraded to lower valued recycled waste paper. Based on this concern, we report the development of novel NaOH/urethane aqueous system for extraction of microfibrillated cellulose from waste paper. The purity of so obtained microfibrillated cellulose (MFC) was evaluated by morphological tests using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and by evaluation of physicochemical properties using Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Morphologies of MFC studied by SEM and TEM showed that the size of purified cellulose fibrils reduced when compared to that of waste paper but fibrils are cleaner and smoother due to the removal of talc and lignin. XRD analysis revealed that MFC exhibits good crystallinity. The utility of sulfonated and pristine microfibrillar cellulose in removal of lead from contaminated water is also reported. Our results show that renewable, sustainable, cheap, and waste biomass like waste paper can be used for producing valuable second-generation high-value products.

Natural Straw–Hemp-Reinforced Hybrid Insulation Materials

“…1−5 Additionally, the thermal insulation improves the indoor hygrothermal comfort while lowering the building energy requirements. 6,7 Among the agriculture wastes, natural CO 2 -storing straw and hemp show enormous potential for reducing embodied carbon emissions in building sectors. 8,9 In this context, hemp is a multifunctional crop with numerous uses across various fields and grows quickly, providing up to four harvests in a single year.…”

“…Technological advances to reduce the carbon footprint are becoming more prevalent nowadays as a result of the rise in energy consumption and greenhouse gas emissions into the environment in recent decades. In this regard, biogenic-based materials from agriculture waste products have attracted immense interest because of CO 2 storage during the utilization phase of their life cycle. − Additionally, the thermal insulation improves the indoor hygrothermal comfort while lowering the building energy requirements. , Among the agriculture wastes, natural CO 2 -storing straw and hemp show enormous potential for reducing embodied carbon emissions in building sectors. , In this context, hemp is a multifunctional crop with numerous uses across various fields and grows quickly, providing up to four harvests in a single year. , Due to the increased farming productivity, remarkable versatility, and growing necessity for eco-friendly materials, hemp has aroused significant interest in the community, with the major advantages of its affordability and cost-effectiveness coupled with its thermal insulation performance. , However, a suitable natural binder is crucial to improving the mechanical strength and thermal insulation of the hemp fiber while maintaining its carbon-storing characteristics. In this regard, wheat straw is selected as a binder, which is one of the major growing crops with the lowest whole-life carbon emissions in comparison to other typical biogenic materials, while not raising the cost, stability, and CO 2 emission. , …”