In this study, highly permeable rigid polyurethanes (PU) incorporating calcium oxide (CaO) (PU/CaO) composite materials were prepared via a facile and economic one-pot synthesis method and characterized for remediation of heavy metal-contaminated urban storm water run-off (USR) in a fixed-bed column. Column tests were conducted to investigate various parameters, and data were interpreted using the Bed Depth Service Time model to predict service time. Among the media tested, 25% CaO-incorporated PU (PU/CaO-25) had the highest adsorption capacity of Cu(II). PU/CaO-25 had about 2.5-fold higher rigidity (0.38 MPa) than a “typical” rigid polymer (0.15 MPa). Hydraulic conductivity tests showed PU/CaO-25 (avg. 0.4 mm) had a permeability (0.108 cm s⁻¹) equivalent or higher than reference sands. Specific structural features of PU/CaO-25 and the remediation mechanism were also determined using FESEM/EDS, XRD, N₂ gas isotherm and chemical equilibrium modeling. Moreover, column tests using simulated USR showed that all heavy metals were removed by PU/CaO-25 to below their regulation levels at ~1,100 bed volumes. Based on the physicochemical properties and functionality, PU/CaO-25 may be useful as an effective filter material in USR treatment and reuse applications.

Currently, the world is moving rapidly toward carbon neutrality, and renewable energy technology is very important in carbon neutrality. Among various renewable energy technologies, wind power is attracting much attention due to its sustainability, resource abundance, and high applicability. This study analyzed wind power patents from 2010 to 2021 to derive current global originality and convergence information. For IP5 countries, the growth stages of technology and the patent convergence networks were inferred by time series analysis and an association rule mining algorithm, respectively. The results showed that, during the analysis period, about 5000 patents were applied on annual average, and it was analyzed that China held the most patents at 48%, followed by the US, Europe, Korea, and Japan. According to the technology convergence network of patent codes from all the IP5 countries, patents related to ‘wind turbines with rotation axes in the wind direction’ occupied a very central position, and ‘power conversion electric or electronic aspects’ and ‘integration of patents related to renewable energy sources in buildings with wind power’ were found to show high connection strength. By country, it was analyzed that the US and China showed high patent competitiveness onshore and possessed many ‘independent power conversion cluster’ technologies. The research hypothesis was that technology development trends can be analyzed and the characteristics of each country can be understood through patent analysis in the wind power field. This hypothesis was analyzed through various patent analysis techniques, and this paper has novelty in that it presents the global megatrend in the wind power field through patent analysis and quantitatively presents the current status of technology development in five major countries.

Magnesium silicate impregnated onto palm-shell waste activated carbon (PPAC) underwent mild hydrothermal treatment under one-pot synthesis, designated as PPAC-MC. Various impregnation ratios from 25 to 300% of MgSiO₃ onto PPAC were tested. High levels of MgSiO₃ led to high Cu(II) adsorption capacity. A ratio of 1:1 (PPAC-MS 100) was considered optimum because of its chemical stability in solution. The maximum adsorption capacity of PPAC-MS 100 for Cu(II) obtained by isotherm experiments was 369 mg g⁻¹. The kinetic adsorption data fitted to pseudo-second-order model revealed as chemisorption. Increasing ionic strength reduced Cu(II) adsorption capacity due to the competition effect between Na⁺ and Cu²⁺. In addition, PPAC-MS 100 showed sufficient adsorption capacity for the removal of Zn(II), Al(III), Fe(II), Mn(II), and As(V), with adsorption capacities of 373 mg g⁻¹, 244 mg g⁻¹, 234 mg g⁻¹, 562 mg g⁻¹, 191 mg g⁻¹, respectively. Three regeneration studies were also conducted. PPAC-MS was characterized using Fourier Transformed Infrared (FTIR), X-Ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Field Emission Scanning Electron Microscope (FESEM). Overall, PPAC-MS 100 is a competitive adsorbent due to its high sorption capacity and sufficient regeneration rate, while remaining economical through the reuse of palm-shell waste materials.