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The reduction of chemical oxygen demand (COD) from palm oil mill effluent (POME) is very significant to ensure aquatic protection and the environment. Continuous adsorption of COD in a fixed bed column can be an effective treatment process for its reduction prior to discharge. Adsorption capacity of bone derived biocomposite synthesized from fresh cow bones, zeolite, and coconut shells for the reduction in the organic pollutant parameter was investigated in this study in a fixed bed column. The effect of influent flow rate (1.4, 2.0, and 2.6 mL/min) was determined at an influent pH 7. The optimum bed capacity on the fabricated composite of surface area of 251.9669 m2/g was obtained at 1.4 mL/min at breakthrough time of 5.15 h influent POME concentration. The experimental data were fitted to Thomas, Adams–Bohart, and Yoon–Nelson models fixed bed adsorption models. It was revealed that the results fitted well to the Adams Bohart model with a correlation coefficient of R2 > 0.96 at different influent concentration. Adsorption rate constant was observed to increase at lower flow rate influent concentration, resulting in longer empty bed contact time (EBCT) for the mass transfer zone of the column to reach the outlet of the effluent concentration. In general, the overall kinetics of adsorption indicated that the reduction in COD from POME using a bone-biocomposite was effective at the initial stage of adsorption. The pore diffusion model better described the breakthrough characteristics for COD reduction with high correlation coefficient. Shorter breakthrough time compared to EBCT before regeneration indicated that the bone composite was suitable and effective for the reduction in COD from POME using fixed bed column adsorption.

Nowadays, microbially induced calcium carbonate precipitation (MICP) has received great attention for its potential in construction and geotechnical applications. This technique has been used in biocementation of sand, consolidation of soil, production of self-healing concrete or mortar, and removal of heavy metal ions from water. The products of MICP often have enhanced strength, durability, and self-healing ability. Utilization of the MICP technique can also increase sustainability, especially in the construction industry where a huge portion of the materials used is not sustainable. The presence of bacteria is essential for MICP to occur. Bacteria promote the conversion of suitable compounds into carbonate ions, change the microenvironment to favor precipitation of calcium carbonate, and act as precipitation sites for calcium carbonate crystals. Many bacteria have been discovered and tested for MICP potential. This paper reviews the bacteria used for MICP in some of the most recent studies. Bacteria that can cause MICP include ureolytic bacteria, non-ureolytic bacteria, cyanobacteria, nitrate reducing bacteria, and sulfate reducing bacteria. The most studied bacterium for MICP over the years is Sporosarcina pasteurii. Other bacteria from Bacillus species are also frequently investigated. Several factors that affect MICP performance are bacterial strain, bacterial concentration, nutrient concentration, calcium source concentration, addition of other substances, and methods to distribute bacteria. Several suggestions for future studies such as CO2 sequestration through MICP, cost reduction by using plant or animal wastes as media, and genetic modification of bacteria to enhance MICP have been put forward.

A wide variety of pollutants are discharged into water bodies like lakes, rivers, canal, etc. due to the growing world population, industrial development, depletion of water resources, improper disposal of agricultural and native wastes. Water pollution is becoming a severe problem for the whole world from small villages to big cities. The toxic metals and organic dyes pollutants are considered as significant contaminants that cause severe hazards to human beings and aquatic life. The microbial fuel cell (MFC) is the most promising, eco-friendly, and emerging technique. In this technique, microorganisms play an important role in bioremediation of water pollutants simultaneously generating an electric current. In this review, a new approach based on microbial fuel cells for bioremediation of organic dyes and toxic metals has been summarized. This technique offers an alternative with great potential in the field of wastewater treatment. Finally, their applications are discussed to explore the research gaps for future research direction. From a literature survey of more than 170 recent papers, it is evident that MFCs have demonstrated outstanding removal capabilities for various pollutants.

East Kalimantan is a province that has the largest coal reserves in Indonesia. One type of coal that is widespread and has low economic value as an energy source is low-rank coal. Low rank coal is a type of coal that has a low calorific value, that is, the calorific value of low rank coal is in the range of the lowest to the highest value, from 3000 cal – 5000 cal. One way to increase the added value of low-rank coal is to convert the coal into activated carbon which can act as an adsorbent medium, this can be done because low-rank coal also has a carbon content of around 30 % W. element in the conversion stage of low-rank coal into activated carbon coal, besides that, we want to know its ability as an adsorbent medium based on the adsorption of the iodine number. The activation process is carried out through the carbonization step which is carried out at a temperature of 600 °C for 3 h and then followed by chemical-physical activation of the carbonized material soaked with chemicals (H3PO4 + Na2HCO3) 2.5 M for 8 h and physically activated at a temperature of 800 °C for 1.5 h. The results obtained were an increase in carbon content and adsorption capacity which respectively reached 73.79 % at carbon content and 1,163.513 mg/g at iodine adsorption number.

Technology and environmental innovations always have a growing emphasis and have affected various industries. Since the cosmetics industry is highly competitive and consumers always desire innovations in products, the cosmetics industry tends to launch new products to satisfy customer desires without exception. Recently, in the area of cosmeceuticals, the application of nanotechnology has been attempting to increase; however, it seems to be tackling certain disadvantages compared to traditional products. Cosmeceuticals based on nanotechnology offer the benefits of product differentiation, improved bioavailability, and prolonged effects of active ingredients. These are widely used as a regulated delivery medium for cosmeceuticals, such as shampoo, nail enamels, lotions, hair serums, and conditioners. Their wide application is attributed to their intrinsic properties, such as rapid penetration, stability, hydrating power, and texture. The ability of the nanoemulsion system to form small- and large-surface nanoparticles enable the bioactive components to be transported into the skin more effectively. Furthermore, natural cosmetics are a general term that refers to all preparations for external conditioning and beautifying of the body from ingredients produced by or found in nature. The purpose of this review is to understand the nature of natural cosmetics which incorporate nanotechnology for better encapsulation and a better drug delivery system. The importance of innovations in the cosmetic industry is also discussed.

Currently, there is increasing interest on low cost and commercially available materials for the adsorption of heavy metals. The vital benefits of adsorption technologies are its potential in reducing the concentration of heavy metal ions using low-cost adsorbent materials. Fruit peel wastes (FPW) are readily available in abundance. Furthermore, it has a high potential as a sustainable adsorbent due to its large quantity of lignocellulosic materials. Realizing this potential, there are many studies on various fruit peels waste adsorbents used in the removal of Pb (II), Cu (II) and Cd (II) ions from wastewater. However, there is no comprehensive review of these adsorbents, especially on the factors that influenced the adsorption capacity. Hence, this review aims to study on the various fruit peels waste adsorbents and the factors by comparing the metal binding capacities, metal removal performances, sorbent dosage, optimum pH, temperature, initial concentration and contact time. Finally, the adsorption mechanisms were also discussed.

Nanotechnology is an innovative area of science that includes the design, characterization, production, and application of materials, devices and systems by controlling shape and size at the nanometer scale (1–100 nm). Nanotechnology incorporation in cosmetic formulation is considered as the hottest and emerging technology available. Cosmetic manufacturers use nanoscale size ingredients to provide better UV protection, deeper skin penetration, long-lasting effects, increased color, finish quality, and many more. Micellar nanoparticles is one of the latest field applied in cosmetic products that becoming trending and widely commercialized in local and international markets. The ability of nanoemulsion system to form small micellar nanoparticles size with high surface area allowing to effectiveness of bioactive component transport onto the skin. Oil in water nanoemulsion is playing a major role as effective formulation in cosmetics such as make-up remover, facial cleanser, anti-aging lotion, sun-screens, and other water-based cosmetic formulations. The objective of this review is to critically discuss the properties, advantageous, and mechanism of micellar nanoparticles formation in nanoemulsion system. Therefore, present article introduce and discuss the specific benefits of nanoemulsion system in forming micellar nanoparticles for cosmetic formulation which become major factors for further development of micellar-based cosmetic segments.