Save water and safe water: Evaluation of design and storage period on water quality of rainwater harvesting system

The present research has been aimed to assess the appropriateness of different aspects of rooftop rainwater harvesting system as an alternative of ground water installed at Chitra Topi. 25 households were purposively selected for the collection of relevant data with the help of interview schedules, focus group discussions, and water sampling. Average rooftop area of surveyed households was 100 m2. Ideal storage system and proper management of surplus during peak seasons can ensure water availability throughout the year. From quality perspective, there are few issues in the physical, chemical and microbiological parameters. But by the introduction of simple components there problems can be rectified to a large extent. Based on results, it is concluded that rain water harvesting systems were shown to be a relatively low cost option for improving a households’ geographical and temporal access to a water source, increasing convenience and decreasing collection times. Keywords: Rainwater, Harvesting, Design, Water qualit

Hybrid Monolith of Graphene/TEMPO-Oxidized Cellulose Nanofiber as Mechanically Robust, Highly Functional, and Recyclable Adsorbent of Methylene Blue Dye

Herein we demonstrate first report on fabrication, characterization, and adsorptive appraisal of graphene/cellulose nanofibers (GO/CNFs) monolith for methylene blue (MB) dye. Series of hybrid monolith (GO/CNFs) were assembled via urea assisted self-assembly method. Hybrid materials were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction patterns, Raman spectroscopy, elemental analysis, thermogravimetric curve analysis, specific surface area, surface charge density measurement, and compressional mechanical analysis. It was proposed that strong chemical interaction (mainly hydrogen bonding) was responsible for the formation of hybrid assembly. GO/CNFs monolith showed mechanically robust architecture with tunable pore structure and surface properties. GO/CNFs adsorbent could completely remove trace to moderate concentrations of MB dye and follow pseudo-second-order kinetics model. Adsorption isotherm behaviors were found in the following order: Langmuir isotherm > Freundlich isotherm > Temkin isotherm model. Maximum adsorption capacity of 227.27 mg g−1 was achieved which is much higher than reported graphene based monoliths and magnetic adsorbent. Incorporation of nanocellulose follows exponential relationship with dye uptake capacities. High surface charge density and specific surface area were main dye adsorptive mechanism. Regeneration and recycling efficiency was achieved up to four consecutive cycles with cost-effective recollection and zero recontamination of treated water