Resource efficiency impact on marble waste recycling towards sustainable green construction materials

India is one of the biggest marble producing country in the world (∼10%). State of Rajasthan has nearly 85% of marble production capacity. Recently, the massive quantity of marble waste fine particulates generated in marble industry has become a major environmental hazard issue. Major minerals present in marble waste are calcite (CaCO3) and dolomite (CaMg (CO3)2). The particle sizes of marble waste particulates has been found to be 200 μm (D90). The chemical composition of marble wastes reveals oxides of calcium (CaO), silica (SiO2), alumina (Al2O3) and alkaline oxides (Na2O, K2O). Apart from that, iron oxide, mica, fluorine, chlorite and organic matter have also been noticed. Marble waste has been explored for possible utilization in industries, thereby it helps in preventing the environmental problems such as dumping and pollution. This article addresses the efficiency of marble wastes for materials development, leading to create some sustainable green composite materials for construction applications

Surface modification of cellulose using silane coupling agent

Recently there has been a growing interest in substituting traditional synthetic polymers with natural polymers for different applications. However, natural polymers such as cellulose suffer from few drawbacks. To become viable potential alternatives of synthetic polymers, cellulosic polymers must have comparable physico-chemical properties to that of synthetic polymers. So in the present work, cellulose polymer has been modified by a series of mercerization and silane functionalization to optimize the reaction conditions. Structural, thermal and morphological characterization of the cellulose has been done using FTIR, TGA and SEM, techniques. Surface modified cellulose polymers were further subjected to evaluation of their properties like swelling and chemical resistance behavio

First & Second Law Analysis of Solar Air Heater

In this paper, thermodynamic analysis is performed for different cases of artificial roughness surface on the absorber plates of solar air heater duct. This analysis has been performed by using the correlations for heat transfer coefficient and friction factor developed experimentally for different type of roughness within the investigated range of operating and system parameters. The comparison has been made for different types of roughness on the basis of first law analysis (effective efficiency) and second law analysis (entropy, irreversibility distribution ratio and entropy generation number)

Natural fiber reinforced polymer composites

The use of natural fibers as a reinforcement for various materials was recorded already in ancient Egypt; however, their rediscovery can be dated to the beginning of 20th century. Currentspecial issueisdevoted to theroleofnatural fibersas reinforcements for various biodegradable and nonbiodegradable polymer matrices. The application of natural fillers can be seen as an approach to adjust material performance of polymer composites supposing that filler/matrix interactions will be optimized and a hygroscopicity of natural fillers will be hindered. This special issue contains 16 papers that highlight a number of reasons for applications of natural fillers in polymer composites. In recent years the discussion about a balance in carbon footprint increased an attractiveness of natural fibers/fillers derived from agricultural sources predominantly from one-year plants

FABRICATION AND STUDY OF LIGNOCELLULOSIC HIBISCUS SABDARIFFA FIBER REINFORCED POLYMER COMPOSITES

Fabrication of polymer composites reinforced with lignocellulosic materials has increased considerably during the last few years. This work reports the synthesis of natural fiber reinforced phenol-formaldehyde (PF) resin matrix based polymer composite using a compression molding technique. Initially the PF resin was prepared by varying the concentration of formaldehyde with a fixed weight of phenol. Polymeric resin of different P: F ratios were subjected for optimization of their mechanical properties. The sample ratio of 1:1.5 (P: F) was found to possess maximum mechanical strength. Then reinforcing of this optimized resin was done by taking different ratios of Hibiscus Sabdariffa (HS) fiber in short form (3mm) to prepare green polymer composites. Polymer composite materials thus prepared were subjected to evaluation of their mechanical properties such as tensile strength, compressive strength, flexural strength, and wear resistance, etc. Optimum mechanical properties were obtained with a fibre loading of 30%.Thermal (TGA/DTA/DTG) and morphological studies (SEM) of the polymeric resin, and composites thus synthesized have also been studied. The results obtained suggest that these fibers can be a superior candidate for the reinforcement of high performance polymer composites