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Death due to diseases from poor sanitation is a serious global issue and it has become one of the priorities of the United Nations' Sustainable Development Goals (i.e., SDG6). This SDG6 aims to provide adequate improved sanitation facilities to over 2.3 billion people around the world who have no or limited access to sanitation, wherein more than two-thirds of these un-served people live in rural areas. One of the strategies for addressing this global issue is through emerging sustainable sanitation technologies such as the Eco-Toilet System (ETS), which uses small amounts of water or is even waterless and recovers nutrients from human waste thereby promoting water-energy conservation, improved sanitation and supplement nutrients essential to plant growth. Social acceptance, however, remains a key barrier in deploying the ETS. A social perception study on the use of the ETS was conducted in a rural community in Mulanay, Philippines. The researchers analyzed the proposed combined technology acceptance model and theory of planned behavior (C-TAM-TPB) using multiple linear regression and the Mann-Whitney U-test to evaluate the perceptions and attitudes of a rural community towards the use of the ETS. The results showed that more than 50% of the respondents are aware of the nutrient value of human excreta and believe that it is usable as fertilizer; however, less than 25% prefer to utilize it for food production. Results also indicate that the behavior of the users is driven by their attitude (β = 0.420, p-value < 0.010). Moreover, the Mann-Whitney U-test results revealed that people who are knowledgeable of the nutrient value of human excreta and are willing to collect them have more positive attitude towards the ETS.

Composites of synthesized reduced graphene oxide (rGO) and titanium dioxide nanotubes (TNTs) were examined and combined at different mass proportions (3:1, 1:1, and 1:3) to develop an electrochemical double layer capacitor (EDLC) nanocomposite. Three different combination methods of synthesis—(1) TNT introduction during GO reduction, (2) rGO introduction during TNT formation, and (3) TNT introduction in rGO sheets using a microwave reactor—were used to produce nanocomposites. Among the three methods, method 3 yielded an EDLC nanomaterial with a highly rectangular cyclic voltammogram and steep electrochemical impedance spectroscopy plot. The specific capacitance for method 3 nanocomposites ranged from 47.26–165.22 F/g while that for methods 1 and 2 nanocomposites only ranged from 14.03–73.62 F/g and 41.93–84.36 F/g, respectively. Furthermore, in all combinations used, the 3:1 graphene/titanium dioxide-based samples consistently yielded the highest specific capacitance. The highest among these nanocomposites is 3:1 rGO/TNT. Characterization of this highly capacitive 3:1 rGO/TNT EDLC composite revealed the dominant presence of partially amorphous rGO as seen in its XRD and SEM with branching crystalline anatase TNTs as seen in its XRD and TEM. Such property showed great potential that is desirable for applications to capacitive deionization and energy storage.

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Highlights Miscanthus sinensis , an invasive plant species as potential source of commercial dyes. Microwave extraction can yield dye extracts from M . sinensis . Optimum condition is at 15 s −150 mL solvent - 540 W microwave power setting. Extraction using 1:1 ethanol-water mixture had highest yield and color-fastness. Mordant application improves binding of flavonoid-based M . sinensis dyes on fabric.

This paper proposes a decision model built on a hierarchical network for optimal selection of biological nutrient removal systems (BNR) in wastewater treatment plants. BNR is an important component of a sustainable wastewater management wherein resource recovery from wastewater becomes an integral part of the municipal wastewater treatment plants (WTP). However, selection of the most appropriate technology or systems requires a multiple criteria analysis. This study focuses on the following criteria namely 1) Economic aspect; 2) Technical aspect; 3) Environmental Aspect; and 4) Space Requirement. The following alternatives were then evaluated: 1) 3 Stage Pho-redox (A2O); 2) 5 Stage Bardenpho (5BP); 3) University of Cape Town (UCT); 4) Virginia Initiative Plant; 5) Sequencing Batch Reactor (SBR); 6) Membrane Bioreactor (MBR). A fuzzy ANP approach with Monte Carlo simulation was used to derive the overall priorities of these alternatives. This decision modelling approach addresses the uncertainty and complexity involved in the selection of appropriate BNR in Metro Manila’s WTP.

This study aimed to enhance boron removal through powdered activated carbon adsorption (PAC) and application of a micro-filtration (MF) process as a pretreatment of a seawater reverse osmosis (SWRO) process. Batch and continuous experiments were conducted to investigate the effect of membrane filtration as well as PAC addition on boron removal in reconstituted seawater. In batch test, two kinds of polyvinylidene fluoride (PVDF) hollow fiber membrane, Module A and Module B, were used to assess the influence of pH and PAC on boron removal, whereas in continuous mode, two MF systems with submerged PVDF flat-sheet membrane were run in parallel. Modules A and B obtained the highest percentage boron removal at pH 9 in the batch experiment with an average value of 47.33%, and their concentration of boron was further reduced after addition of PAC increasing the removal to 51.33 and 69.33%, respectively. For the continuous operation, PAC addition decreased the boron concentration by 20–30 and 40% in the reactor and effluent, respectively. On the other hand, only 5% reduction was obtained inside the reactor and 30–40% in the effluent for the system without PAC. Thus, operating the system at high pH with PAC addition could enhance the performance of the adsorption-MF system, which can be used as a pretreatment for the SWRO process.