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Olive activated biochar (OAB) was prepared from waste de-oiled olive pomace (sansa esausta, SE) through carbonization followed by combined KOH and thermal activation. The activation process was optimized using central composite design (CCD) with pyrolysis temperature, activation time and KOH to pyrolized SE mass ratio (KOH/PSE) as independent variables, and yield, methylene blue number (MBN) and iodine number (ID) as responses. Optimized OAB was subjected to fixed bed adsorption of 100 mg L−1 methylene blue dye. Numerical optimization resulted in optimum process setting of 362°C pyrolysis temperature, 61-min activation time and 0.81 KOH/PSE under which the optimized activated biochar produced 31% OAB, MBN of 679 and ID of 899. Thomas and Yoon-Nelson models best fit the fixed bed adsorption data implying that methylene blue adsorption conforms to Langmuir isotherm and obeys pseudo-second order reversible reaction kinetics with no axial dispersion. The theoretical adsorption capacity of OAB is 131 mg g−1 with theoretical time required for 50% sorbate breakthrough of 54.69 h. These results show the potential application of OAB in dye adsorption.

Abstract: This work describes the low temperature synthesis of novel nanosized Au/La1−x Sr x MnO3 (x ≈0.4) and Au/La0.85Sr0.15CrO3 composites and investigates their potential as anodic catalysts for propane reforming. The pristine La1−x Sr x MnO3 (x ≈0.4) and La0.85Sr0.15CrO3 were prepared by a modified nitrate–citrate Pechini method and the process was optimized in order to obtain high surface area perovskite powders. These materials with nanometric or sub-micrometric grain size have been isolated as a single-phase and used for the preparation of the composite. A homogenous distribution of nanosized gold particle (<5 nm) was deposited on the perovskite powders surface by an ultrasound-driven synthesis. The catalytic behavior of these inorganic composites was investigated for the following propane reforming processes, i.e. steam reforming, partial oxidation and autothermal reforming. Good propane conversions in the partial oxidation conditions were detected for sub-hundred nanometer La1−x Sr x MnO3 perovskite and the role of gold as a promoter for this process was assessed. In particular, nanosized gold on La1−x Sr x MnO3 resulted in an increase of the perovskite stability under all catalysis conditions. The influence of water steam in the feeding gas stream was also tested. The low influence of gold presence in catalytic tests of Au/La0.85Sr0.15CrO3 suggested poor gold catalytic activity in the tested conditions but a presumable role of gold on the stabilization of the Mn mixed oxidation state in the case of the manganites. [Copyright &y& Elsevier]

The topic of sustainability of reinforced concrete structures is strictly related with their durability in aggressive environments. In particular, at equal environmental impact, the higher the durability of construction materials, the higher the sustainability. The present review deals with the possible strategies aimed at producing sustainable and durable reinforced concrete structures in different environments. It focuses on the design methodologies as well as the use of unconventional corrosion-resistant reinforcements, alternative binders to Portland cement, and innovative or traditional solutions for reinforced concrete protection and prevention against rebars corrosion such as corrosion inhibitors, coatings, self-healing techniques, and waterproofing aggregates. Analysis of the scientific literature highlights that there is no preferential way for the production of "green" concrete but that the sustainability of the building materials can only be achieved by implementing simultaneous multiple strategies aimed at reducing environmental impact and improving both durability and performances.

The paper represents the "state of the art" on sustainability in construction materials. In Part 1 of the paper, issues related to production, microstructures, chemical nature, engineering properties, and durability of mixtures based on binders alternative to Portland cement were presented. This second part of the paper concerns the use of traditional and innovative Portland-free lime-based mortars in the conservation of cultural heritage, and the recycling and management of wastes to reduce consumption of natural resources in the production of construction materials. The latter is one of the main concerns in terms of sustainability since nowadays more than 75% of wastes are disposed of in landfills.

This review presents "a state of the art" report on sustainability in construction materials. The authors propose different solutions to make the concrete industry more environmentally friendly in order to reduce greenhouse gases emissions and consumption of non-renewable resources. Part 1-the present paper-focuses on the use of binders alternative to Portland cement, including sulfoaluminate cements, alkali-activated materials, and geopolymers. Part 2 will be dedicated to traditional Portland-free binders and waste management and recycling in mortar and concrete production.

The aim of the present research work was the synthesis of molecularly imprinted polymers (MIPs) with a rod-like geometry via "mesophase polymerization". The ternary lyotropic system consisting of sodium dodecyl sulfate (SDS), water, and decanol was chosen to prepare a hexagonal mesophase to direct the morphology of the synthesized imprinted polymers using theophylline, methacrylic acid, and ethylene glycol dimethacrylate as a drug model template, a functional monomer, and a crosslinker, respectively. The obtained molecularly imprinted microrods (MIMs) were assessed by performing binding experiments and in vitro release studies, and the obtained results highlighted good selective recognition abilities and sustained release properties. In conclusion, the adopted synthetic strategy involving a lyotropic mesophase system allows for the preparation of effective MIPs characterized by a rod-like morphology., Competing Interests: The authors declare no conflict of interest.