Lotus (Nelumbo nucifera): a multidisciplinary review of its cultural, ecological, and nutraceutical significance.

This comprehensive review systematically examines the multifarious aspects of Nelumbo nucifera, elucidating its ecological, nutritional, medicinal, and biomimetic significance. Renowned both culturally and scientifically, Nelumbo nucifera manifests remarkable adaptability, characterized by its extensive distribution across varied climatic regions, underpinned by its robust rhizome system and prolific reproductive strategies. Ecologically, this species plays a crucial role in aquatic ecosystems, primarily through biofiltration, thereby enhancing habitat biodiversity. The rhizomes and seeds of Nelumbo nucifera are nutritionally significant, being rich sources of dietary fiber, essential vitamins, and minerals, and have found extensive culinary applications. From a medicinal perspective, diverse constituents of Nelumbo nucifera exhibit therapeutic potential, including anti-inflammatory, antioxidant, and anti-cancer properties. Recent advancements in preservation technology and culinary innovation have further underscored its role in the food industry, highlighting its nutritional versatility. In biomimetics, the unique "lotus effect" is leveraged for the development of self-cleaning materials. Additionally, the transformation of Nelumbo nucifera into biochar is being explored for its potential in sustainable environmental practices. This review emphasizes the critical need for targeted conservation strategies to protect Nelumbo nucifera against the threats posed by climate change and habitat loss, advocating for its sustainable utilization as a species of significant value.

Spatial distribution, source identification, and risk assessment of heavy metals in riparian soils of the Tibetan plateau.

Riparian soils in the lower sections of the Lhasa River were chosen as the research focus, to examine the characteristics and sources of heavy metals in riparian soils of high-cold regions. To investigate the influence of various factors on the geographical distribution of heavy metals, three horizontal and one vertical profiles were considered. The geoaccumulation index, prospective ecological risk index, and enrichment factor were used to evaluate the extent of soil contamination. Correlation analysis and the positive-matrix-analysis receptor model were used to quantitatively examine the sources of the elements. According to the soil-evaluation, the topsoil was more polluted than the deep soil. Overall, the soil was slightly degraded and posed minor ecological concern. Cd was the primary contributor to the overall contamination, with moderate and considerable risk levels at certain locations. Five sources were identified for the six heavy metals. Transportation and agricultural production were the principal sources of Cd. Ni and Cr were mostly connected to agricultural practices and weathering of parent-soil materials. Pb and Zn were mostly related to geological history, geothermal development, and traffic pollution. Mineral resource development has had a major impact on Cu. Non-carcinogenic risk index of each heavy metal and their total value were <1, indicating they are not harmful to human health. The riparian soil of the Lhasa River Basin contains heavy metals from various sources; therefore, it is important to monitor these heavy metals. This study provides a scientific foundation for the safe utilization and classification of soils in high cold regions.

Study on adsorption and recovery utilization of phosphorus using alkali melting-hydrothermal treated oil-based drilling cutting ash.

Oil-based drill cutting ash (OBDCA) was treated by alkali melting-hydrothermal method and used as novel adsorbent (AM-HT-OBDCA) for the recovery of phosphorus (P) in water body. The experiment parameter for preparation of AM-HT-OBDCA was optimized, including alkali melting ratio (MOBDCA: MNaOH), alkali melting temperature and hydrothermal temperature. The adsorption process of phosphorus on AM-HT-OBDCA was fit well with the pseudo-second-order model and the Langmuir model. The calculated theoretic adsorption capacity of phosphorus on AM-HT-OBDCA was 62.9 mg/g. The adsorption behavior was spontaneous and endothermic. The effect of pH value and interfering ions on the adsorption of phosphorus in AM-HT-OBDCA was investigated. The main existing form of adsorbed phosphorus on AM-HT-OBDCA was sodium hydroxide extraction form phosphorus (NaOH-P), including iron form phosphorus (Fe-P) and aluminum form phosphorus (Al-P). Precipitation and ligand exchange were the main mechanisms of phosphorus adsorption on AM-HT-OBDCA. The AM-HT-OBDCA used for phosphorus adsorption (AM-HT-OBDCA-P) could be further utilized as fertilizer to promote plant growth. The results of this study provide fundamental data and evaluation support for resource utilization of OBDCA. These results will also provide a reference for the adsorption and recovery utilization of phosphorus using solid waste-based adsorbent.

Enhanced adsorption of tetracycline using modified second pyrolysis oil-based drill cutting ash.

In this work, second pyrolysis oil-based drill cutting ash (OBDCA-sp) was modified using NaOH and cetyltrimethylammonium bromide (CTAB), respectively. The modified OBDCA-sp was used as the novel adsorbent for adsorption of tetracycline (TC) in aqueous solutions. The original and modified OBDCA-sp were characterized by SEM, XRD, FTIR, zeta potential analysis, contact angle, and BET. The maximum theoretical adsorption quantity (45 ℃) for TC was calculated as 1.7 mg/g using CTAB-OBDCA-sp as the adsorbent. The adsorption isotherm of TC on OBDCA-sp was fitted well with Freundlich model and the adsorption kinetic was illustrated by pseudo-second-order model. Neutral condition was favorable for the adsorption of TC. The result of regeneration experiment indicated the reusability of OBDCA-sp. The hydrogen bonding was the possible mechanism for TC adsorption. This paper developed the novel surface modification methods of OBDCA-sp and provided an approach for the resource utilization of OBDCA-sp as an environmental functional material.

Treatment and novel resource-utilization methods for shale gas oil based drill cuttings - A review.

The oil exploration and production (E&P) industry has made outstanding contributions to gross domestic product (GDP) growth in many countries. In recent years, the gap between energy supply and demand has widened, and, simultaneously, demand for clean energy has gradually increased. As an emerging clean energy source, shale gas has received extensive attention. However, the environmental problems caused by oil and gas extraction and production should not be underestimated. Oil-based drill cuttings (OBDC) are typical hazardous solid wastes produced during oil/gas exploration and production processes. In addition, oil-based drill cuttings ash (OBDCA) is the main product of treated OBDC and should be further utilized to avoid pollution and waste of resources. This review describes relevant policies and regulations for the OBDC. The main treatment methods for OBDC have been systematically summarized. Compared to the standard method for resource utilization of OBDCA, a novel approach was proposed to utilize OBDCA as an environment-friendly functional material for environmental remediation. The future development prospects for OBDC were envisioned to achieve sustainable development goals.

Enhanced Adsorption of Rhodamine B on Modified Oil-Based Drill Cutting Ash: Characterization, Adsorption Kinetics, and Adsorption Isotherm.

In this paper, phosphoric acid (H3PO4), hydrochloric acid (HCl), and hydrogen peroxide (H2O2) were employed for the modification of oil-based drill cutting ash (OBDCA) for the first time. The adsorption of rhodamine B (RhB) on modified oil-based drill cutting ash (MOBDCA) in an aqueous medium was investigated. H2O2-modified OBDCA had the optimal adsorption efficiency for RhB. The physical and chemical properties of MOBDCA were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), ζ-potential, N2 adsorption-desorption isotherm, and pore size distribution. The effect of the pH value (3-11), reaction time (10-720 min), and initial RhB concentration (10-200 mg/L) on RhB adsorption was discussed. The adsorption kinetics highly fitted with the pseudo-second-order model (R 2 > 0.99), which indicated that the adsorption process was dominated by chemisorption. The adsorption isotherm fitted well with the Langmuir and Freundlich models (R 2 > 0.97), which indicated the monolayer adsorption process and the heterogeneous adsorption process, respectively. The theoretic adsorption capacity (50 mg/g) for RhB was achieved by H2O2-modified OBDCA. This paper provides a promising method of resource utilization of OBDCA to treat organic pollutants.

Activation of Peroxymonosulfate Using Secondary Pyrolysis Oil-Based Drilling Cuttings Ash for Pollutant Removal.

In this study, the utilization of secondary pyrolysis oil-based drilling cuttings ash (OBDCA-sp) to activate peroxymonosulfate (PMS) for pollutant removal was investigated. The chemical and physical properties of OBDCA-sp were explicitly analyzed via multiple characterization. The activation efficiency of OBDCA-sp for PMS was tested using humic acid (HA) as the target pollutant. 92% of HA and 52% of total organic carbon in solution could be removed using OBDCA-sp-activated PMS under optimal conditions: OBDCA-sp dosage at 4 g/L, PMS concentration at 4 mmol/L, HA concentration at 10 mg/L, and pH value at 7. After four cycles, 84% removal rate of HA could still be achieved using OBDCA-sp to activate PMS. The main catalysis elements for PMS activation in OBDCA were postulated to be Fe(III), Co(III), and Mn(III), based on X-ray photoelectron spectroscopy and X-ray diffraction results. The results of the quenching experiment indicated that SO4 •-, •OH, and 1O2 were the main reactive oxygen species (ROS) and that 1O2 was the dominant ROS in the HA removal process. Radical trapping experiments indicated the presence of SO4 •-, •OH, and 1O2 in the reaction system. This study presented a novel utilization path of OBDCA in the field of environmental remediation.

Treatment of oil-based drilling cuttings using the demulsification separation-Fenton oxidation method.

In this study, demulsification separation-Fenton oxidation technology was employed as a combined technology to treat total petroleum hydrocarbons (TPH) in oil-based drill cuttings (OBDC). Batch experiments were carried out to optimize the technology parameter. Under the optimal condition, 70% and 51% TPH removal rate was obtained for demulsification technology and Fenton oxidation technology, respectively. Eighty-five percent of TPH removal rate was obtained using combination technology of demulsification separation and Fenton oxidation. Multiple characterizations were used to analyze the physical and chemical properties of treated OBDC. The result of XRD pattern indicated the combination technology had no obvious effect for structure phase of OBDC. The results of FTIR, GC-MS, TG-DTG and SEM were used to characterize the treated OBDC. This paper provides an efficient and feasible combined technology for OBDC treatment, which expands a new strategy for the removal of TPH from solid waste.