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Oxidative desulfurization (ODS) is a swiftly rising organosulfur compounds eradicating system, effective enough at a mild temperature and pressure, overwhelming the necessity of costly hydrogen in the traditional HDS systems. In this study, pure LaVO4 photocatalyst was prepared using the hydrothermal approach and employed for deep oxidative desulfurization application in the aerobic environment under visible-light irradiations. The as-prepared photocatalyst semiconductor material was characterized by FTIR, SEM, UV–vis DRS and Raman analyses. The examined photocatalyst presented a narrow bandgap, a small particle size, high photo-responsive monoclinic phase, high light photons capturability, plenteous active sites accessibility and reduced recombination of photogenerated charge carriers, ensuing a good visible-light-driven deep oxidative desulfurization ability. The photocatalytic material was tested for its performance over different petroleum refinery diesel pool fraction streams including hydrodesulfurization unit diesel rundown, mild hydrocracking unit rundown gas oil, heavy kerosene oil and the ultimate diesel oil blend, containing organosulfur compounds ranging from disulfides to the stringent organosulfur compounds, with the quantity lying between 57 and 863 ppm. The kinetic study was found in agreement with the pseudo-first-order kinetics. The conceivable desulfurization mechanism was also anticipated. Moreover, the recyclability of the photocatalytic material was also discussed.

Amorphous spherical-shaped copper–manganese oxide for the catalytic combustion of benzene were successfully obtained by a wet granulation process under different calcination temperatures. The low-temperature (400 °C) calcined catalysts—which showed a larger BET specific surface area, low temperature reducibility, and an amorphous phase—were more active for the catalytic combustion of benzene than the high-temperature calcined catalyst which underwent the amorphous to crystalline phase transition. The catalytic activity tests, depending on the operating parameters, suggested that amorphous spherical-shaped copper–manganese oxide have potential applications for remedying VOC pollution.

Biochar produced during the thermochemical decomposition of biomass not only reduces the amount of carbon emitted into the atmosphere, but it is also an environment-friendly replacement for activated carbon and other carbon materials. In this review paper, researches on biochar are discussed in terms of production method and application. Different processes for biochar production, such as pyrolysis, gasification, hydrothermal carbonization, etc., are compared. Physical and chemical activation methods used to improve the physicochemical properties of biochar and their effects are also compared. Various environmental application fields of biochar including adsorption (for water pollutants and for air pollutants), catalysis (for syngas upgrading, for biodiesel production, and for air pollutant treatment), and soil conditioning are discussed. Recent research trend of biochar in other applications, such as fuel cell, supercapacitor, and hydrogen storage, is also reviewed.

Hydrodeoxygenation (HDO) of guaiacol in a batch-type reactor at 40 bar and 250 °C was investigated using six different catalysts, Pt/HZSM-5, Pt/Mesoporous Beta, Pt/HBeta, Pt/MMZ Beta , Pt/Al-MCM-48, and Pt/Si-MCM-48. Among various catalysts, Pt/Mesoporous Beta and Pt/HBeta, which have both large pores and strong acid sites, showed guaiacol conversions larger than 90%. The main product species of HDO of guaiacol was cyclohexane. Meanwhile, Pt/Al-MCM-48 and Pt/MMZ Beta , which are mesoporous catalysts with weak acid sites, led to lower guaiacol conversions than Pt/Mesoporous Beta and Pt/HBeta and the main product components were cyclohexane and 1,1-bicyclohexyl resulting from C C coupling reactions.

Deactivated waste activated carbon due to the deposition of boron in the exhaust gas from an incinerator was regenerated by the treatment with surfactant, HCl, and NH3. The catalysts were characterized using BET surface area, ICP, XPS and FT-IR spectra. Sequential treatment with surfactant and HCl removed the adsorbed boron very effectively. NH3 treatment increased the number of functional nitrogen groups in regenerated sample. For NH3 selective catalytic reduction (SCR) of NO, sequential treatments with surfactant, HCl, and NH3 showed the highest DeNOx activity, attributed to the increased metal removal efficiency, specific surface area and amount of nitrogen functional groups on the surface.

Effects of loading method and amount of platinum on the hydroisomerization of n-dodecane were investigated. Platinum was supported on SAPO-11 by incipient wetness, ion exchange, or atomic layer deposition. Characterization of catalysts was carried out using N2 adsorption, XRD, NH-TPD, TPR, and pyridine-IR. The dispersion of the Pt (IE 0.2)/SAPO-11 and the Pt (ALD 0.6)/SAPO-11 are 0.65 and 0.59, respectively, which are much higher than those of the catalysts prepared by incipient wetness method. The Pt(IW)/SAPO-11 catalyst exhibited the best isomerization activity in the hydroisomerization of n-dodecane, which is attributed to the highest reducibility.

The copyrolysis of plywood and block polypropylene (PP) was carried out in a batch reactor system, and analyzed via TGA and Py-GC/MS. Specific attention was paid to the diagnosis of the interaction between the plywood and block polypropylene during their copyrolysis, with the relationship between the interaction and improvement in the quality of the bio-oil explained. From the TGA results, the window of the decomposition temperature of PP during copyrolysis was slightly increased, indicating that the products from the pyrolysis of plywood affected the characteristic of the pyrolysis of PP. The new products not observed in the single component pyrolysis were formed and the quantities of products appeared in the single component pyrolysis also varied. In the batch reactor system, the bio-oil yield was increased and the amounts of oxygen and water decreased. Consequently, the heating value of the bio-oil was increased.

The capability for the adsorption of Cu(II)-ion with mesoporous silica materials, such as MCM-41, SBA-15 and XPD-2412, after functionalizing with amine groups, such as aminopropyltriethoxysilane (APTES), N (β-aminoethyl) γ-aminopropylmethyl dimethoxysilane (AEAPMDMS) and N 1 -(3-(trimethoxysilyl)-propyl) diethylenetriamine (TMSPDETA), was investigated in this study. N 2 adsorption, XRD and elemental analysis methods were performed to gain an understanding of the structure and surface properties of the mesoporous silica materials. Of the absorbent materials, MCM-41, functionalized with APTES, showed the best activity for the adsorption of Cu(II)-ion. Compared with the mesoporous silica materials functionalized with APTES, those functionalized with AEAPMDMS and/or TMSPDETA showed lower adsorption capabilities, which may have been due to the locations of the amine groups. Most of the amine-organic domains were suggested should exist near the opening of channels or external surfaces. Furthermore, the rate of adsorption of Cu(II)-ions matched well with a pseudo-second-order kinetic model.

The objective of the present study is to investigate the performance of MoO 3 /SiO 2 as a catalyst for double bond migration from 2-butene to 1-butene. The effects of MoO 3 addition on catalytic properties over SiO 2 were analyzed through BET surface area, XRD, ammonia-temperature programmed desorption (NH 3 -TPD) and FT-IR of adsorbed pyridine. The highest activity of the 10% MoO 3 /SiO 2 catalyst in double bond migration of 2-butene can be explained by the highest number of the weak acid sites. Based on the NH 3 TPD and the FT-IR of pyridine adsorption results, the increase in the overall number of acid sites can be ascribed to an increase in the number of Lewis sites by the addition of MoO 3 .

Mesoporous V2O5/TiO2 particles with a spherical shape were prepared via spray pyrolysis, using P123 as a structure directing agent, and applied to the catalytic oxidation of 1, 2-dichlorobenzene (DCB). The texture properties of the prepared V2O5/TiO2 particles were monitored by changing the P123/Ti molar ratio from 0.03 to 0.07 and the vanadia content from 3 to 7 wt%. All the prepared samples had mesopores, but without any pore ordering. The sample prepared with a P123/Ti = 0.05 (molar ratio) had the largest surface area (142 m2/g) and smallest pore size (6.6 nm). The quantity of vanadia loading affected the texture properties as well as the crystallographic form of the V2O5/TiO2 particles. The major crystal phases of mesoporous V2O5/TiO2 particles were anatase, but 7–30% were formed in the rutile phase, which depended on the quantity of vanadia loading. However, the catalytic activity of V2O5/TiO2 particles progressively increased with increasing quantity of vanadia loading. With 7 wt% V2O5/TiO2 particles, 94% decomposition of 1, 2-DCB was achieved at 400 °C. The mesoporous V2O5/TiO2 particles prepared via spray pyrolysis showed higher catalytic activity compared with that prepared via the conventional impregnation method, which was due to the high dispersion of vanadia on the surface of pores. From the results obtained, the mesoporous V2O5/TiO2 particles prepared via spray pyrolysis were confirmed to have excellent activity for the oxidation of 1, 2-DCB, particularly at temperatures lower than 350 °C.

In this study, a mesoporous material (MCM-41), crystalline microporous zeolite (HY), and amorphous silica (XPO-2412) were functionalized with three kinds of amine groups, namely 3-aminopropyltriethoxysilane (APTES), N(β-aminoethyl) γ-aminopropylmethyl dimethoxysilane (AEAPMDMS), and N1-(3-(trimethoxysilyl)-propyl) diethylenetriamine (TMSPDETA) and their performances for formaldehyde adsorption evaluated. BET, XRD, and elemental analysis were used to evaluate structural and surface characteristics of the adsorbents. Due to its large specific surface area, the adsorption efficiency of MCM-41 increased with the amount of amine groups (MCM-41/APTES XPO-2412/AEAPMDMS > HY/AEAPMDMS. The adsorption efficiency was the highest at 30 °C, while decreasing rapidly above 30 °C, suggesting an optimum temperature for interaction between the amine groups and formaldehyde. Given the results of this study, amine functionalized MCM-41 is believed to have great potential as an adsorbent for removing indoor formaldehyde at room temperature.

The object of the present study is to apply layered double hydroxide catalysts to remove sulfur dioxide from sulfone compounds, by-products of Oxidative Desulfurization (ODS). The effects of Mg/Al ratio, aging temperature, and calcination on the characteristics of the layered double hydroxide catalysts were investigated through the BET surface area, XRD, SEM, and temperature-programmed desorption of CO2. The layered double hydroxide catalyst with an Mg/Al ratio of 2 or 3 and with an aged temperature of 150 °C was found to be optimal for the decomposition of dibenzothiophene sulfone. It has since been ascribed to a well-developed LDH structure and has the greatest amount of base site. The optimized layered double hydroxide catalysts were found to have high activity and stability during the catalytic removal of sulfur dioxide from sulfones that were in ODS diesel.

A facile preparation method of activated carbon (AC) honeycomb monoliths is suggested in this work. A composite consisting of activated carbon, organic polymer binder (LDPE), and organic lubricant was effectively extruded above the melting temperature of the organic polymer in the shape of a honeycomb monoliths (dimensions: 256 cells in 4 cm × 4 cm). Three types of AC powders are investigated to elucidate the relationships between the processibility of the honeycomb monoliths and the size of their AC particles. The surface area of activated carbon filters increases as the size of the AC particle increases. This may be due to pore blocking by organic polymer binder on the surface of the AC particle. The mechanical properties of the honeycomb monolith are enhanced drastically when extrusion molding is used as compared to the use of a conventional press-molding process.

Various polymer-modified mortars using recycled artificial marble waste fine aggregate (AMWFA) were prepared and investigated for the purpose of feasibility of recycling. Styrene–butadiene rubber (SBR) latex and polyacrylic ester (PAE) emulsion were employed as polymer modifier, and compared each other. The replacement ratio of AMWFA was also changed to investigate the effect of it on physical properties. Adding polymer cement modifier into mortar reduced water–cement ratio, and PAE was the more effective polymer cement modifier to reduce water–cement ratio than SBR. PAE emulsion-modified mortar increased the air content entrained as the proportion of PAE was increased. There was little difference in water absorption between SBR latex and PAE emulsion. The compressive strength decreased in the presence of polymer cement modifiers compared to that of no polymer cement modifiers, but the compressive strength of 20% of polymer–cement ratio was higher than that of 10%. After the hot water resistance test, both compressive strength and flexural strength were decreased.