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Spent adsorbents from the S-Zorb technology are hazardous wastes. Reactivating and recycling the spent S-Zorb adsorbents is of great significance to environmental protection. However, no report concerning this subject has been found yet. Herein, we have developed an acid-base coupling method to reactivate the spent S-Zorb adsorbents. To achieve this goal, the deactivation factors of the adsorbents were studied. The results show that the formation of Zn2SiO4 phase, which results in loss of active phase (ZnO) for sulfur storage, is the main deactivation factor. The acid-base coupling method can transform Zn2SiO4 into soluble Zn2+ via nitric acid, followed by precipitation as Zn(OH)2 with sodium hydroxide addition. After calcination, the loss of ZnO can be supplemented. The newly formed ZnO bears a willow-leaf shape that is remarkably different from the original one. Also, it has smaller particle size compared to that of fresh adsorbents. Of note is that mesopores and Lewis acid sites are created over the adsorbents via the acid-base coupling method, accelerating the mass transfer and conversion of sulfur compounds. Carbon deposited over the adsorbent surface is removed and metal sulfides (ZnS and NiS) are oxidized into metal oxides (ZnO and NiO) via calcination of the spent adsorbents. The desulfurization efficiency of the reactivated adsorbent is superior to that of the regenerated adsorbent and reaches a level comparable to that of the fresh adsorbent in gasoline desulfurization.

An improved gas recovery system (GRS) using activated-carbon fiber-cloth (ACFC), electrothermal swing adsorption (ESA), and carrier gas recirculation was shown to capture and recover >99% isobutane while reducing N2, H2O, and energy consumption. ACFC-15 was selected as the adsorbent after a trade-off of adsorption capacity and cost. Carrier gas recirculation was used for the first time to conserve N2 and H2O at relative humidity (RH) up to 80% while recovering volatile organic compound (VOC) (i.e., isobutane). When RH is 24% and 77%, overall energy (EOverall) consumed with recirculation decreases by 2.5% and 26% compared to without recirculation, respectively. Recommendations are provided to reduce the gap of energy consumption of the GRS with recirculation based on idealized and experimental conditions. Unique contributions and importance of this work are demonstrating that carrier gas recovery and reuse can be used to better conserve N2, H2O, and energy; analyzing specific energy consumption values; and proposing improvements of such a system to let the GRS with recirculation operate closer to idealized conditions.

Solar irradiation (λ ≥ 290 nm) has been introduced into a traditional Fe2+ activated persulfate (PS) system (Fe2+/PS). The combination system of solar light, Fe2+ and PS system (solar/Fe2+/PS) exhibited a rapid and continuous oxidation of chloramphenicol (CAP) in solution, and showed great advantages over the Fe2+/PS process by accelerated degradation efficiency. A presumed reason is that Fe2+ was slowly and continuously recycled by solar light, and the reductive photolysis Fe3+ to Fe2+ was promoted concomitantly with the production of additional hydroxyl radical (HO ). The optimal dosages of PS and Fe2+ were determined by batch experiments. pH significantly influenced CAP degradation, and an acidic condition favored the reaction. Both HO and sulfate radical (SO4 −) were considered to be the mainly oxidant to remove CAP, and HO had a higher contribution than SO4 −. The presence of HCO3−, NO3−, NO2−, H2PO4−, HPO42− demonstrated adverse effects on CAP decay in solar/Fe2+/PS process. Coexisting Cl− ions slightly accelerated the CAP degradation rate at an appropriate concentration (0.6–6 mM) but gradually inhibited at a higher Cl− (12–36 mM) content. The results clearly showed that CAP presented the slowest degradation rate in wastewater, and the colloids should be taken into consideration prior to the application of solar/Fe2+/PS for wastewater treatment. Nonetheless, up to 89.7%, 94.7%, and 65.4% of CAP were removed from the filtrate, permeate, and retentate within 100 min, respectively. It is expected that the modified process could be applied for CAP removal from wastewater containing a considerable colloids/organic content. Finally, 8 major intermediate products were identified and the preliminary degradation pathways were proposed.

Over last decades, the complexity and variability of hepatocellular carcinoma (HCC) has significantly interfered with the effectiveness of traditional treatment, and has gradually become a main obstacle and bottleneck for HCC therapy. In order to explore the innovative therapeutic strategy to further improve the cancer diagnosis and treatment, we herein proposed a thermal-induced magnetic nanosystem with good biocompatibility that therapeutic cargo controllable release relies on 808 nm laser irradiation. This nanosystem was designed by co-loaded the manganese-doped magnetic nanoparticles and photosensitizer indocyanine green into the matrix of temperature sensitive polymer, with further capturing negatively charged YAP1 siRNA on the surface, to finally obtain the heat-induced manganese-doped magnetic nanocarriers (HMM-siRNA NCs). Our study found that the photosensitizer on the exposure of 808 nm laser irradiation could generate continuous heat to rupture the thermal-sensitive polymer matrix, that controllable release the embedded ICG and Mn0.8Fe2.2O4 NPs for NIR/MR imaging, ICG-mediated heat and ROS could induce the thermal expansion and rupture of HMM-siRNA NCs, causing the evident thermal swelling of lysosomes to induce the cell apoptosis. Besides, YAP1 siRNA can decrease the YAP1 expression in HCC down to approximately 35%, reducing the cell proliferation and migration. Such NIR/MRI guided low-temperature PTT and siRNA-mediated gene therapy strategy lead to tumor cell death by using various and complementary approach, thereby achieving controllable and effective comprehensive treatment in the presence of 808 nm laser irradiation. Our designed delivery complex can accomplish the precise cancer treatment on the tumor site by responding to the external 808 nm laser, and its non-toxic metabolites demonstrate the excellent biocompability for extensive use either anti-cancer therapy or various disease from clinical research.

To investigate the pore confinement effect of MoO 3 /Al 2 O 3 catalyst for deep hydrodesulfurization, a series of MoO 3 /γ-Al 2 O 3 catalysts were prepared via impregnation method. All catalysts had almost the same physicochemical properties, such as the specific surface area, apparent morphology, microstructure, coordination of Al atom and acidity, and differed in the pore size. The control experiments results showed that enlarging the pore size from 3.6 to 8.8 nm increased the desulfurization efficiency of 4,6-dimethyldibenzothiophene (4,6-DMDBT) from 62.6% to 95.0%, then decreased to 71.3%. The catalyst with a pore size of 5.9 nm displayed the optimum hydrodesulfurization performance. The larger pores weaken the effect of polarization of Al 3+ on the van der Waals interactions between the layers of active phase and result in more stacking of MoS 2 . The more stacked MoS 2 contribute to more edge and corner active sites for the catalysts with the pore size of 5.9 nm, which resulted that this catalyst exhibited the highest reaction rate and sulfidation degree of Mo species, lowest reduction temperature and largest amount of chemisorbed CO. The reaction and characterization results revealed that the smaller mesopores favored the accessibility of 4,6-DMDBT to the edge sites of MoS 2 active phase, whereas the larger ones promoted the reactant molecules to the corner sites. Compared to the catalyst with mono-pore size, the catalyst with hierarchical mesopore structure had a higher hydrodesulfurization activity through the synergism of small and large pores. The larger pores enable 4,6-DMDBT to reach the active sites located in the small pores and promote the accessibility of the reactants to the corner sites of hexagonal shaped MoS 2. This catalyst possessed a lower ratio of hydrodesulfurization products to direct desulfurization ones.

In this work, ZSM-5-based mesostructures were synthesized via two-step integrated synthesis strategy. Mesoporosity and textural properties of ZSM-5-based mesostructures were controlled by varying several parameters, which can affect either alkali dissolution or mesostructure re-assembly. The effects of these synthesis parameters on mesopore regularity and textural properties of ZSM-5-based mesostructures were also identified and optimized initially at 0.25 L scale. Based on the results at 0.25 L scale, the process was scaled up to 5 and 50 L scale. A new strategy for transformation of alkali dissolution to mesostructure re-assembly during two-step integrated synthesis for scale-up is proposed. The results of the samples prepared at 5 and 50 L scale revealed that the present strategy is stable and reproducible for industrial scale manufacturing and applications.

Ethyl mercaptans which commonly exist in natural gas have to be removed to a low level due to their toxic, odorous and corrosive properties. Herein, a novel Fe-N-modified active carbon catalyst was prepared for the ethyl mercaptans removal. The Fe3O4 phase provides main active sites for catalytic oxidation of the ethyl mercaptans. Introduction of nitrogen groups increases content and dispersion of the active Fe3O4 sites, which exposes more active sites accessible to the ethyl mercaptans. Besides, the formed nitrogen groups, including pyridinic-N, pyrrolic-N also contribute to adsorption and activation of the sulfur compounds. Therefore, sulfur capacity of the novel catalyst (238.3 mg/g) is more than three times that of the iron modified active carbon (70.1 mg/g) and nearly four times that of the pure active carbon (62.2 mg/g). The ethyl mercaptans are oxidized into diethyl disulfides and metal sulfonates over the novel catalyst. All the oxidation products as well as the ethyl mercaptans are adsorbed by the catalyst. The sulfur capacity of the exhausted catalyst can be restored to nearly eighty percent of the fresh one after a simple thermal treatment.

International audience; In the present study, two strategies for improving the catalyst efficiency either by (1) raising the effective diffusion coefficient or (2) reducing the diffusion length of zeolite catalysts are presented. These two strategies are exemplified by the preparation of (i) ordered mesoporous material with zeotype secondary building units and (ii) self-assembled nanosized zeolites. The textural properties, acidity, and the results from the cumene cracking show that the strength and amount of Brønsted acid sites of the mesoporous materials are inferior, due to their amorphous pore walls. Even though the lifespan of ordered mesoporous material with zeotype secondary building units during cumene cracking can be improved due to the effective diffusion coefficient enhancement, the strength and amount of Brønsted acid sites related to the reaction are not akin to conventional microporous zeolites. While the self-assembled nanosized zeolites with short diffusion length shows enhanced catalytic performance by diffusion controlled reactions.

CdSe magic-sized quantum dots (MSQDs) families 392 (F392) and 461 (F461) exhibiting bright band gap emission and little trap emission were synthesised via a non-injection one-pot approach, where cadmium acetate dihydrate (Cd(OAc) 2 ·2H 2 O) and selenium dioxide (SeO 2 ) were used as Cd and Se source compounds, respectively, and N-oleoylmorpholine was selected as reaction medium. The approach does not have to adding any long-chain fatty acid or phosphine ligands. The investigation showed that N-oleoylmorpholine played three roles of reaction medium, reductant of SeO 2 , and stabilizer of QDs. The reduction reaction step of SeO 2 to Se 0 was important to the regulation and control of the reactivity of Se precursors as well as the thermodynamic equilibrium between nucleation and dissociation of the nuclei. The parameters including the reaction temperature, Cd-to-Se feed molar ratio, and growth periods were investigated. The synthetic approach allowed long-term growth and stability of CdSe MSQDs in a wide range of temperature and Cd-to-Se feed molar ratios. Different families developed independently from different nuclei. The degree of supersaturation (DSS) impacted the presence of CdSe NCs with different sizes. The moderate DSS favored the common development of different species coexisting in the same batch, the relatively high DSS favored the long-term existence of CdSe MSQDs family with high thermodynamically stability. New growth protocol was proposed to explain the formation mechanism of CdSe MSQDs. The characterization of CdSe MSQDs by the transmission electron microscopy (TEM), X-ray diffraction spectroscopy (XRD) and Energy Dispersive X-ray Spectroscopy (EDS) have been also accomplished.