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During the wintertime, concrete pavements experience harsh exposure conditions due to the presence of both the freezing–thawing and wetting–drying cycles. Airport concrete pavements are commonly de-iced using chloride-free organic salts such as potassium formate or potassium acetate. However, these materials contain alkali ions which can have harmful effects on both the cement matrix and the aggregate. Specifically, there is an increased risk of occurrence of the alkali–silica reaction (ASR). The goal of this research was to estimate the influence of potassium formate on the potential of causing alkali–silica reaction in aggregates with different categories of reactivity (R0, R1, R2). The accelerated mortar bar test and its modification (which involves replacing sodium hydroxide solution with a potassium formate solution) were used. Detailed SEM-EDS examinations were performed to confirm the presence of alkali–silica reaction and to analyze the influence of potassium formate on the microstructure of mortar.

Air conditioning using a liquid desiccant (LD) is an energy-efficient air purification and cooling system. However, high energy is required to concentrate or regenerate the LD. This study aimed to investigate the characteristics of membrane fouling in more detail and determine control strategies for LD concentrating using membrane distillation (MD). Two different LDs—lithium chloride (LiCl) and potassium formate (HCOOK)—were used. Because LDs require high concentrations by nature (i.e., 40 wt% for LiCl and 70 wt% for HCOOK), the concentration was started from half of those concentrations. This resulted in a flux decline with severe membrane fouling during the concentration using MD. Different membrane fouling mechanisms were also observed, depending on the LD type. Three different physical membrane fouling control methods, including water flushing (WF), air backwashing (AB), and membrane spacer (SP), were introduced. Results showed that WF was the most effective. Both AB and SP showed a marginal change to no cleaning; however, an initial flux with SP was about 1.5 times higher than no cleaning. Therefore, WF combined with the SP could maintain a high flux and a low fouling propensity in the treatment of a high-concentration solution using MD.

Microplastics (MPs) are considered an important stratigraphic indicator, or ‘technofossils’, of the Anthropocene. Research on MP abundance in the environment has gained much attention but the lack of a standardized procedure has hindered the comparability of the results. The development of an effective and efficient method of MP extraction from the matrix is crucial for the proper identification and quantifying analysis of MPs in environmental samples. The procedures of density separation used currently have various limitations: high cost of reagents, limited solution density range, hazardous reagents, or a combination of the above. In this research, a procedure based on density separation with the use of potassium formate water solution (H2O/KCOOH) in controlled conditions was performed. Experimental sediment mixtures, spiked with polyethylene (PE), polystyrene (PS), polyurethane (PUR) and polyethylene terephthalate (PET) particles were prepared and an extraction procedure was tested in the context of a weight-based quantitative analysis of MPs. This article discusses the effectiveness and safety of the method. It additionally provides new information on the interactions between MP particles and the mineral matter of the sediment. Results were acquired with the use of instrumental methods, namely thermogravimetry (TG), Fourier Transform Infrared (FTIR) spectroscopy, Field Emission Scanning Electron microscopy and Energy Dispersive spectrometry (SEM/EDS), as well as X-ray fluorescence (XRF) analysis.

Xanthan gum solutions have gained increasing interest for their use as environmentally friendly chemicals in the oil industry. Xanthan is compatible with most concentrate brines used for controlling formation damage and fluid loss. Particularly, formate brines reinforce the ordered structure of the biopolymer in solution, gel strength, and the specific gravity of the resulting fluid. In this paper, we studied the effect of thermal aging on the rheological behavior of xanthan solutions as a function of the concentration in potassium formate. Ionic strength below a threshold concentration does not prevent the degradation of the structure of xanthan after being submitted to aging at 165 °C. Aged solutions show an important loss of strength in their mechanical properties, lower pH, and higher content in furfural and hydroxymethylfurfural. Highly concentrated formate brines are necessary to maintain the strength of the rheological properties after exposure to high-temperature environments.

The present study intended to study the dehumidification performance of KCOOH solution both experimentally and numerically. The heat and mass transfer model for internal cooling dehumidifier was built. The influences of different parameters on dehumidification performance were identified by experiments. Results indicated that the air temperature and solution has negligible influence on dehumidification performance. However, the air humidity and solution temperature have significant influence on dehumidification due to its close relationship with mass transfer driving force. The proposed model can simulate the dehumidification performance in terms of absolute moisture change well with the MARD of 6.05%.