Systematic literature review of solar-powered landfill leachate sanitation: Challenges and research directions over the past decade.

Researchers have documented the negative effects of refractory chemicals and emergent pollutants in landfill leachate (LL) that cannot be degraded using conventional methods. The propagation, invasion, and deleterious effects of several LL hazards affect aquatic species, the environment, and food outlets, causing significant safety issues. These include cancer risks, chronic exposure, and reproductive consequences. Alternatively, solar energy is a sustainable solution for treating landfill leachate to benefit humans and the environment. In this work, a thorough bibliometric and systematic analysis of studies that employed solar energy for landfill leachate remediation over the past decade was conducted in order to determine trends, and future research areas. In addition to the energy demand, the economic aspect and the advantages of using solar power to treat landfill leachate were discussed. Additionally, the study gives specific suggestions for future research purposes and important problems. The reviewed literature revealed that combining solar-based physical-chemical and biological processes has proven to be the most efficient method for landfill leachate degradation. It also appears from the bibliometric study that more collaboration and contribution are needed to develop solar-based landfill leachate treatment. This study concludes that solar-powered landfill leachate remediation techniques would considerably increase the effectiveness of treated leachate reutilization, advancing the cause of environmental sustainability.

Surface Modification of TiO2 Nanotubes Prepared by Porous Titanium Anodization via Hydrothermal Reaction: A Method for Synthesis High-Efficiency Adsorbents of Recovering Sr Ions.

The recycling of strontium ions (Sr2+) from sea water has been well known for its good cost-effectiveness and environment friendliness. Herein, we modified the surface of TiO2 nanotubes (TNTs) prepared by porous titanium anodization via hydrothermal (HT) reaction and synthesized a highly efficient adsorbent for the repeated recycling of Sr2+. TNTs with a high specific surface area were manufactured on porous titanium by internal anodic oxidation. The as-prepared TNTs were treated by HT method to synthesize adsorption materials with a tubular bottom and grass-type top structure loaded with Na+. The surface cracks were eliminated by annealing pretreatment, and the investigation found that the 6 h HT reaction most effectively increased the Na+ content in the adsorbent. The as-synthesized adsorbents (HT-6TNTs) were used to recover Sr2+, and the maximum adsorption efficiency (approximately 100%) and adsorption equilibrium were observed within 10 h. Meanwhile, three consecutive cycles of adsorption experiments proved the uniform behavior of the HT-6TNTs in the reproducible recycling of Sr2+. In addition, by increasing the anodization time of TNTs from 0.5 to 3 h, the maximum adsorption capacity can be increased from 4.68 to 36.15 mg·unit-1, approximately 7.7 times higher.

Nanostructured Ti07Mo03O2 as Efficient Non-Carbon Support for PtRu Catalysts in Direct Methanol Fuel Cells.

This study was focused on a new strategy by investigating whether the novel Ti0.7Mo0.3O2 material can be used as a conductive support for PtRu to prevent carbon corrosion and improve catalyst activity as the novel Ti0.7Mo0.3O2 support has some functional advantages. The 30 wt% PtRu/Ti0.7Mo0.3O2 catalyst showed the highest current density at the complete potential, which is approximately 12-fold and 1.4-fold higher than that of the commercial 20 wt% Pt/C (E-TEK) and 30 wt% PtRu/C (JM) catalysts, respectively, at 0.6 V (NHE) toward the methanol oxidation (MOR). Our data suggest that this enhancement is a result of the electronic Pt structure change upon its synergistic interaction with Ti0.7Mo0.3O2 support and the improved mass transport kinetics of PtRu/Ti0.7Mo0.3O2 compared to the carbon support (Pt or PtRu). The PtRu/Ti0.7Mo0.3O2 catalyst exhibited a much higher stability than carbon-supported catalysts because of the strong metal/support interactions between the Pt particles and Ti0.7Mo0.3O2, the inherent structural and chemical stability, and the corrosion resistance of the Ti0.7Mo0.3O2 in acidic and oxidative environments.