SHahram SHarifnia

Abstract Hydrogen production as a clean and sustainable energy source, particularly through water splitting, is considered one of the fundamental challenges in the field of renewable energy. In this study, the process of hydrogen production through photocatalytic water splitting using photocatalysts Bi?WO? and CuBi?O? with different weight ratios is investigated and analyzed. The two photocatalysts, CuBi?O? and Bi?WO?, were synthesized via a hydrothermal method and subsequently combined in various weight percentages. Due to their unique properties in light absorption and charge transfer enhancement, these photocatalysts have the potential to exhibit high efficiency in hydrogen production from water. To characterize the Bi?WO? and CuBi?O? photocatalysts, several analytical techniques were employed. Subsequently, the impact of forming a heterogeneous junction between these two materials on water splitting performance was examined. All reactions were conducted under UV-Visible light in a 160 mL quartz reactor. Experimental results indicate that although the pure Bi?WO? and CuBi?O? photocatalysts produce hydrogen at rates of 131.87 ?molg?¹ h?¹ and 165.56 ?molg?¹ h?¹, respectively, the heterogeneous Bi?WO?/CuBi?O? junction in the optimized sample significantly increases the hydrogen production rate to 341.25 ?molg?¹ h?¹ compared to the individual photocatalysts. This enhancement in efficiency is attributed to improved light absorption, increased electron and hole lifetimes, and reduced electron recombination.   Keywords: Photocatalyst, CuBi?O?, Bi?WO?, Water Splitting, Heterojunction

The aim of this research is to increase the efficiency of the photocatalyst composed of bismuth chromate and copper oxide along with reduced graphene oxide under visible light to remove phenol. Bismuth chromate has shown good activity as a promising photocatalyst in removing organic pollutants from aqueous solution; But due to the high rate of electron/hole recombination, it has been used less. To reduce the electron/hole recombination rate of this photocatalyst, there are several methods, including combining with other semiconductors, among the semiconductors, metal oxides have shown good performance. In this research, the combination of bismuth chromate and copper oxide along with reduced graphene oxide was prepared using hydrothermal synthesis method and ternary composite with different molar ratios. Among them, the composite had a better performance in removing phenol. By examining effective parameters such as catalyst dose, solution pH, initial concentration of phenol and determining optimal conditions including catalyst dose equal to 1mg/L, pH equal to 5 and initial concentration of phenol, the photocatalytic performance improved and the removal rate reached 97%. Using the results of XRD, FTIR, FESEM, EDX and UV-vis analysis, the optical and structural properties of the synthesized photocatalysts were checked, and the results indicate the correct and good synthesis of the photocatalysts and the higher photocatalytic performance of the ternary composite compared to other photocatalysts under visible radiation. This composite still shows good performance after 4 reuses. The ternary composite prepared in this research has a favorable performance for the photocatalytic decomposition of phenol pollutant under visible light irradiation.

In this research, desulfurization through an adsorption method using activated carbon derived from oak seed husk was investigated for a model fuel consisting of n-hexane solvent and the sulfur compound dibenzothiophene. The activation process utilized chemical activation with phosphoric acid. The adsorption process was conducted in a batch system, and the nitrogen adsorption-desorption isotherm for the synthesized sample was >  

  synthesis of supported Monolith with Honeycomb method and Characterize Structural investigation

   Currently, removing sulfur from gas or liquid fuels is one of the most important tasks of the oil refining industry. Sulfur compounds such as mercaptans, thiophenes, benzothiophenes, and dibenzothiophenes can be converted into SOx during gas or liquid combustion. Various physical, chemical and biological methods have been investigated in order to remove sulfur impurities from petroleum compounds, which include HDS, ADS, BDS, EDS and ODS. In this research, the oxidative desulfurization process of simulated oil cut containing 1000ppm di-benzothiophene using heterogeneous catalysts with loading of potassium tungsten oxide based on natural kaolin zeolite along with hydrogen peroxide as oxidizing agent and acetonitrile as solvent. The extraction was done in which catalysts with 5, 10, 15, 20% by weight of potassium tungstate based on metakaolin were made by dry inoculation method. After testing the %W catalyst /metaKaolin 15 was chosen as the best catalyst in this research . Then, using Design Expert version 11 software, the experiments were designed and the optimal operating conditions (t=60min, T=60Co, O/S=12, cat=0.04g) were determined and the amount of desulfurization from the model oil in these conditions 98.9% was obtained. Also, the corresponding catalyst still had an acceptable performance after five recovery steps.

The goal pursued in this research is to increase the photocatalytic performance of Ag2CrO4(ACO) under visible light irradiation to remove alizarin red (AR) color pollutant. Due to the narrow energy gap and also the recombination rate of this photocatalyst, its photocatalytic performance decreases. To solve this problem, NiFe-LDH photocatalyst, which is a member of the double-layer hydroxide family, was used along with ACO. Three composites with different molar percentages (AN1-1: AN2-1: AN1-2) were prepared, among which composite (AN1-1) Ag2CrO4@50% NiFe-LDH50% was the best sample with a removal rate of 97.1% in AR degradation. . Also, the properties, structure and characteristics of pure Ag2CrO4 and NiFe-LDH and their composites were determined by XRD, FESEM, FTIR, EDX mapping and UV-Visible analyses. It was found that Ag2CrO4@NiFe-LDH composites with the Z design structure, in addition to increasing the active sites and increasing the specific surface area, reduce the recombination rate of pure Ag2CrO4 and NiFe-LDH. From the technique of designing Box Behnken experiments, which is one of the most commonly used designs in response surface methodology (RSM), to optimize operating conditions and investigate the effect of 4 independent parameters: catalyst amount (0.5-1.5 g/L), solution concentration (5 -20 mg/L), pH (12-4) and light intensity (52-13 W) were used. The importance of independent parameters and their interaction was determined using ANOVA. Using numerical optimization, the optimal values of the selected parameters equal to 1.34 g/L of catalyst, solution concentration of 16.45 mg/L, pH = 10.74 and light intensity of 15.53 W were obtained as optimal conditions with a desirability coefficient of 1.00 and an absorption value of 95.71%. The closeness of adjusted R2 (0.9838) and predicted R2 (0.9507) values show that this model can be successfully used for prediction. Also, after 3 cycles, the degradation efficiency of AN1-1 decreased by only 8.16% and no significant deactivation was observed, indicating the high stability and remarkable reusability of the photocatalyst; Therefore, the prepared composite can be suitable for the photocatalytic removal of wastewater containing colored pollutants.  

In thisstudy, the efficiency of an advanced photocatalytic oxidation process for theremoval of Methylene Blue (MB) dye from synthetic wastewater wasinvestigated.     composiwas used, and the process was examined under visible light irradiation. Tooptimize the conditions for photocatalytic decomposition, the Box-Behnkendesign method was employed. -   compositeswith different molar ratios (1:2, 1:1, 2:1) were synthesized using thehydrothermal method. The highest photocatalytic removal efficiency in theinitial experiments was found to be 85%, attributed to the BC-2:1 composite.XRD, FTIR, FESEM, EDX, and UV-Vis analyses were employed to identify thestructural and optical properties of the synthesized photocatalysts.FE-SEMshowed relatively uniform distribution of copper oxide (CuO) nanoparticles onbismuth chromate ( ) nanotubes. UV-Vis analysisindicated that the highest photocatalytic performance was achieved by theBC-2:1 composite, with a band gap of approximately 1.73 eV compared to thelower performance under visible light irradiation of pure CuO and . This enhanced photocatalyticactivity can be attributed to the heterogeneous p-n synergistic effect. Pure   and CuO samples individually were not capableof effectively performing the photocatalytic reaction for Methylene Blue (MB)removal. However, the composite samples exhibited highly desirablephotocatalytic activity. Photodegradation experiments were conducted with theproposed optimal parameters, including an initial MB concentration of 18.89mg/L, a pH of 11, a catalyst dose of 0.99 mg/L, and a light intensity of 29.2W. The suggested system's response (percentage removal) was 91.97%.The averagepercentage removal of the dye, based on three repeated measurements, was90.06%, indicating the applicability of the proposed model. Furthermore, the -

  Separation of theethylene/ethane mixture by the cryogenic distillation method is a process withsignificant energy consumption and high operating and capital costs due to theclose boiling point of the components and their low relative volatility and similarmolecule sizes. Reducing these costs and lowering energy consumption requiresan efficient separation procedure, and adsorption separation is a promisingenergy-efficient process for ethylene/ethane separation among the separationmethods. In order to use the adsorption separation process successfully,providing an adsorbent that can perform separation at low pressures andtemperatures near ambient is a necessity.The Cu-MOF-74 metal-organicframework is utilized as an adsorbent in this research to separate ethylene andethane. Because of the open metal sites, this framework is favorable for theformation of complexes with unsaturated hydrocarbons (ethylene). One of thepurposes of this research is to investigate and measure ethylene and ethaneadsorption at 278, 298, 313, and 353 K temperatures and to provide the isothermparameters. Additionally, the conventional methods of synthesis oforganic-metallic frameworks have been investigated, and the mechano-chemicalsynthesis method was chosen to synthesize this MOF. Prior to that, wedeveloped, evaluated, and reported scalable techniques for synthesis inindustrial production for them, as well as optimized their operating parametersdue to the unavailability of some of the required raw materials and theexpensive cost of some due to their rarities.Disodium hydroquinone saltwas synthesized using water as a solvent, and an effective approach forproducing it in the industry with a high yield was provided. In contrast toearlier techniques, this one is carried out at room temperature and pressure anddoesn't require the use of hazardous, expensive, or hazardous solvents. The2,5-dihydroxyterephthalic acid (DHTA) ligand was subsequently synthesized usingthis compound, and the DHTA synthesis's operational parameters have beenoptimized. These parameters, which were used to synthesize the chemical with an83% concentration, are temperature (200 ?), pressure (10 bar), the molar ratioof the catalyst to the reactant (2.085), and the reaction time (4.18 hours).Finally, the synthesized DHTA was used to produce Cu-MOF-74 adsorbent. Themaximum amount of adsorption for ethylene and ethane, respectively, was 7.33and 5.26 mmol/g, determined by measuring the amount of adsorption at 278 K. Theamount of adsorption and selectivity decreased and increased, respectively,with increasing temperature. The maximum selectivity occurred at 313 K, andethylene was adsorbed more than twice as much as ethane.

   Water is a vital resource for humans, both for consumption and the production of goods. Today, with the rapid development of industries, water pollution caused by heavy metals has become one of the most significant environmental problems and a key goal of wastewater treatment. Among the methods for water purification, membrane filtration has garnered considerable attention. In this study, we conducted the fabrication and investigation of polyethersulfone-based nanocomposite membranes using the phase inversion process, incorporating graphite carbon nitride nanoparticles and nanoparticles functionalized with salicyl aldehyde, indigo, and indigo carmine. This study aims to examine the impact of adding nanoparticles on heavy metal removal and anti-fouling properties. We performed Fourier transform infrared spectroscopic analysis, X-ray diffraction, and scanning electron microscopy to study the structure of nanoparticles and verify the functionalization of nanoparticles. Additionally, scanning electron microscope analysis, contact angle measurements, and porosity assessment were conducted to investigate the structure of nanocomposite membranes. The fabricated membranes were evaluated for pure water flux, the ability to remove Cu+2 heavy metal ions, antifouling properties, and flux recovery ratio against a milk powder solution. The results demonstrate an increase in the hydrophilicity and pure water flux of nanocomposite membranes when nanoparticles are added, primarily due to the presence of hydrophilic functional groups on their surface. Surface scanning electron microscope images and cross-sections of the nanocomposite membranes show that all the produced membranes possess an asymmetric structure, characterized by a compact, thin, and dense upper layer and a porous bottom layer with finger-like structures. Regarding the filtration of copper nitrate solution, nanocomposite membranes containing 0.5%wt of g-C3N4/Indigo and g-C3N4/IndigoCarmin displayed removal efficiencies of 97.43% and 98.35%, respectively. The membrane containing 1.5%wt of g-C3N4/Salicylaldehyde exhibited a 98.05% removal of copper ions, significantly outperforming the pure polyethersulfone membrane and nanocomposite membrane containing unmodified nanoparticles, which achieved removal efficiencies of 37.23% and 70.65%, respectively. This makes the modified nanofiltration membranes highly suitable for practical applications. The flux recovery ratio for nanocomposite membranes containing 1.5%wt of g-C3N4/Salicylaldehyde, 0.5%wt of g-C3N4/IndigoCarmin, and 0.5%wt of g-C3N4/Indigo was found to be 86.58%, 90.16%, and 79.93%, respectively. These values indicate superior antifouling properties compared to the pure polyethersulfone membrane, which achieved a 61.44% flux recovery ratio. Keywords: Membrane filtration, Graphite carbon nitride, Wastewater treatment, Surface properties, Antifouling

  فرآيند كاتاليزوري   با استفاده ازتترا كلريد تيتانيوم   وديگر تركيبات وابسته، رايج ترين پروسه توليدي براي چرخه زيگلر ناتااست.روش هاي ديگري در اين چند وقت اخير ابداع شده اند كه همگي منتج به توليد وپليمريزاسيون گشته است ولي رايج ترين و در دسترس ترين روش و بومي سازي شده ترينروش، همين روش مي باشد.اين روش با توجه به تثبيت شدن در تمام جهات اكنون روشياقتصادي مي باشد و از همه لحاظ توجيه پذيري اقتصادي دارد كه مي توان   به بومي سازي شرايط آزمايشگاهي،به وفور در دسترس بودنتجهيزات آزمايشگاهي ،ساخت پلنت هاي متعدد توليدي ،بازدهي بالاي توليد محصول وپليمريزاسيون و... نام برد ولي با توجه به ماهيت پژوهشي علم و اينكه هميشه بهدنبال راهي براي بهبود يافته ها و دستاوردهاي قبلي مي باشد سعي شده كه نقاطضعف   يافته هاي قبلي پوشش داده   شده و به بهبود و خلق پيشنهادات جديد بپردازد.در ابتدا با اضافه كردن كردن عناصر فلزي مانندFeCl3   و SiCl3 در فاز گازي[22] ،كاتاليزورهايي را ساخته و به وسيله روش ودستگاههاي آزمايشگاهي از قبيل SEM،   ETو EDX تاثير اينعناصر بر افزايش فعاليت كاتاليست مورد بررسي قرار گرفتند.سپس در فاز دوغابي واكنش مورد بررسي قرارگرفت.در انتهاي نتايج بررسي در جدولي مقايسه ايگردآوري و جمع بندي گرديد.بحث پاياني كه مهمترين و اصلي ترين موضوع اينپژوهش و شاكله اصلي آن مي باشد به اصلاح و افزايش واكنش پذيري كاتاليست هاي زيگلرناتا مي پردازد.با توجه به وجود الكل و حلال هگزان در چرخهواكنش و توليد كاتاليست ، وجود آلودگي ها و آلكوكسي ها در واكنش اجتناب ناپذير ميباشد.آلكوكسي ها باعث تخريب واكنش اصلي و انجام واكنش كاذب و متعاقبا عدم ايجادزنجيره پليمريزاسيون و توليد پليمر ميگردند.لذا بايستي آلكوكسي ها   به حد قابل قبولي كه نقطه تعادلي بين واكنشپذيري و اقتصادي بودن واكنش باشد كاهش يابند.براي اين منظور روش جديد شستشوي كاتاليستابداع گرديده است.ابتدا با نمونه گيري 6 متر مكعب از پايه كاتاليستمحلول در هگزان شروع به تعيين دماي نقطه ابتدايي آزمايش   است مي نماييم.اين دما اندكي كمتر از نقطه جوشهگزان است. نمونه گرفته شده را به آزمايشگاه منتقل كرده و مو پس از تهيه سياليكدست و كاملا حل شده ، پس از تبخير حلال ،آن را به پودر كاتاليست تبديل مي نماييم.پودرحاصله را پس از تبديل به قرص به دستگاهIR جهت تشخيص ميزان آلودگي به آلكوكسي ها منتقل مي نماييم ونتايج حاصل را ثبت و ضبط مي نماييم. سپس بطور متوالي 14 مرحله ديگر را همين ترتيبكه نمونه را در بازه دمايي بعدي تا توليد قرص كاتاليست پيگيري نموده و جهت تست واندازه گيري آلكوكسي به آزمايشگاه ميفرستيم.با آناليز نتايج حاصله دستگاه IR   مشاهده ميشود كه نرخ كاهش از مرحله پنجم به بعدبشدت كاهش يافته زيرا اغلب آلودگي آلكوكسي ها  در همان پنج مرحله ابتدايي كاهش يافته و نرخ كاهش بعد از مرحله پنجم باتوجه به مقدار هگزان مصرفي و مقوله اقتصادي آن قابل اعتنا نمي باشد.لذا شرايط فرآيندي مرحله پنجم شستشو كه دماي55 درجه و ميزان مجاز الكوكسي 100PPM     مي باشد را به عنوان مبنا انتخاب نموده و از اينبه بعد براي رسيدن به ميزان100 PPM تا پنج مرحله شستشو مي دهيم.  

  Unsaturated polyester resins have manyapplications in the composite industry. In thicker pieces made with this resin,a lot of heat is released in a short time during curing, inaddition, they have a low heat transfer coefficient. In thick sections, hightemperature differences between the center and the sample walls cause internalstresses. Therefore, adding particles with high thermal conductivity can helpto eliminate this defect. In this study, to investigate the changes in theproperties of unsaturated polyester resin containing Boehmite nanoparticles inweight percentages of 0.02, 0.05 and 0.3 and its hybrid with graphite andalumina particles in different weight percentages were used. The thermalconductivity of the samples made in heat fluxes of 1, 3 and 4 watts wasinvestigated. Also, DMA test was used to evaluate themechanical properties of the samples and the results were evaluated. Accordingto the results of thermal conductivity test, the highest rate of increase inthermal conductivity was obtained in the sample containing 0.05% by weight ofboehmite nanoparticles, which increased by 149% compared to neat resin. Also, inthe performed hybrid samples, the highest thermal conductivity coefficient isfirst related to boehmite / graphite hybrid, containing 0.025% by weightof boehmite / 0.025 graphite with thermal conductivity of 9.93 watts perkelvin and then for boehmite / alumina hybrid sample. Contains 0.05% by weightof boehmite / 0.5% by weight of alumina with a thermal conductivity of 7.45watts per kelvin, which have increased by 108% and 56%, respectively, comparedto neat resin. Also with you to the results obtained from the DMA test withincreasing the content of boehmite nanoparticles continuous storage modulusincreased. The highest increase in storage modulus was obtained in the 0.3% byweight sample of boehmite, which could be due to the stiffness and hardness ofboehmite nanoparticles. The OH groups at the particle surface can increase thestorage modulus relative to neat unsaturated polyester resin by creatinggravitational interactions with the OH, COOH and ester groups of alkyd chainsof unsaturated polyester resin. The use of boehmite / alumina particle hybridsalso led to better results than boehmite / graphite particle hybrids, due tothe fact that alumina particles have a smooth surface and spherical morphologythat reduce friction and improve mechanical properties in the system. The useof three-part boehmite / graphite / alumina hybrid in unsaturated polyesterresin increased heterogeneity and formed a non-uniform network in the systemcompared to neat resin.

In this research, the efficiency of simultaneous adsorption/photocatalyst system in the color decomposition and removal has been investigated. The composite from of MCM-22 zeolite, titanium dioxide and cerium metal nanoparticles and curcumin natural compound has been used. TiO2 nanoparticle has been layered by the reaction of the zeolite and titanium butoxide solution and then, the cerium metal was fixed on it using cerium nitrate salt. The photocatalyst reactor has been slurry type and the experiments were conducted in the presence of visible light using xenon lamp. Morphology and chemical analyses were investigated using FESEM, FT-IR, XRD, DRS, PL, Zeta potential and TGA. The efficiency of this system was evaluated by considering the operating conditions including cerium metal concentration, photocatalyst loading, initial contaminant concentration and pH of the contaminant solution on the contaminant degradation reaction rate of the contaminant and the total contaminant loading raduction of the solution, and basad on this result, the optimum conditions were obtained. Furthermore, the performance of the simultaneous process system in methylene blue dye removal was compared with the individual adsorption and photocatalytic process. By using the spectrophotometry method, the maximum dye removal was obtained in the feed concentration of 5 ppm, the photocatalyst concentration of   2.5 g / L and   H=11. Finally, the dye removal results were 11, 32 and 96%   in the photocatalyst   rocess, the adsorption process, and the simultaneous adsorption / photocatalyst system, respectively.

Managing the disposal of waste hydrocarbon gases in industrial complexes is one of the most important issues for industrial units due to global warnings to reduce the long-term dire consequences for the ecosystem and its economic losses. A significant portion of the waste gases sent to the burner are light gaseous compounds such as methane, ethane, propane and four carbon and hydrogen inclusions, which by recovering them, not only the release of combustion products into the environment and its harmful consequences can be avoided, but also global warming and over-consumption of economic resources can be prevented. In the present study, GTL process simulation and optimization are investigated among other burner gas recovery methods due to the production of more high-quality products and better process economy. In this method, in addition to recovering heavy hydrocarbons, methane gas is converted into valuable materials such as gasoline, LPG or LNG with a lower sulfur content than usual. This process was further enhanced by the addition of a membrane unit, which increased hydrocarbon production by 13% to justify the increased fixed and operating costs of the membrane unit. Also, by returning the water leaving the membrane to the reforming reactor, the amount of water vapor requested from the water, electricity and steam unit is reduced by 92%. Furthermore, carbon dioxide produced by GTL reactor in reforming reactor is used to increase the production of synthesized gas by up to 7%.   

AbstractToday, the issue of pollutants in water resources such as organic matter and minerals is of great importance. Among the available water pollutants, paints, which are a group of organics with a complex structure and enter the environment through various processes such as dyeing, can be considered as the main sources of water pollution.According to research on the removal of dyes from water sources, photocatalytic degradation (a branch of the advanced oxidation process) is an efficient and low-risk method or the so-called green. Among the photocatalytic compounds developed, the two compounds zinc oxide and titanium dioxide are known to be more widely used, so-called more industrial, because of their cost-effectiveness, high jump, no pollution, and low energy requirements. Zinc oxide compound, which is white and environmentally friendly, is a non-toxic compound with high stability, high light sensitivity, wide energy gap and photocatalytic properties and high efficiency, which has attracted much attention in electron production.Pure photocatalysts such as ZnO have disadvantages such as rapid electron-hole recombination rates and low photocatalytic efficiencies in aqueous media, which can be improved by a variety of methods. Is another photocatalyst. In this way, the photocatalytic property of the host semiconductor is significantly increased. In recent years, studies have been conducted on the positive effect of ZnO on the photocatalytic process, which include increasing the specific surface area, coupling ZnO with other semiconductors, correcting ZnO with metals and non-metals, reducing particle size, and sensitizing zinc oxide. Due to the importance of dye removal from wastewater of various industries such as textiles, in this study, the efficiency of the photocatalytic process of perovskites with ABO3 structure such as LaNiO3 has been investigated. LaNiO3 perovskite has good photocatalytic properties and is one of the semiconductors with limited band gap that is activated when exposed to visible light, the synthesis of which is also investigated in this study.  

   در اين پروژه اثر پيش پليمريزاسيون بر روي هموپليمريزاسيون اتيلن با كاتاليزور زيگلر-ناتاي صنعتي      TiCl4/MgCl2 مورد مطالعه قرار گرفت، وثوابت سينتيكي هموپليمريزاسيون اتيلن در شرايط مختلف      پيش پليمريزاسيون (دما، مقدار اتيلن ، فشار هيدروژن و نسبت Al/Ti ) محاسبه شد ، كه مشخص شد ثواب    سينتيكي شروع واكنش (Ka)، انتشار(kp) و غيرفعال شدن(kd) به شرايط پيش پليمريزاسيون بستگي    دارد. در حقيقت نشان داده شد با انجام پيش پليمريزاسيون مي توان رفتار كاتاليزوردر همو پليمريزاسيون    اتيلن تحت كنترل داشت. و با انجام پيش پليمريزاسيون به خواص پليمر و مورفولوژي مورد نظر رسيد و    شرايط را بهبود بخشيد. در اين پروژه اثر پيش پليمريزاسيون بر روي هموپليمريزاسيون اتيلن با كاتاليزور زيگلر-ناتاي صنعتي      TiCl4/MgCl2 مورد مطالعه قرار گرفت، وثوابت سينتيكي هموپليمريزاسيون اتيلن در شرايط مختلف      پيش پليمريزاسيون (دما، مقدار اتيلن ، فشار هيدروژن و نسبت Al/Ti ) محاسبه شد ، كه مشخص شد ثواب    سينتيكي شروع واكنش (Ka)، انتشار(kp) و غيرفعال شدن(kd) به شرايط پيش پليمريزاسيون بستگي    دارد. در حقيقت نشان داده شد با انجام پيش پليمريزاسيون مي توان رفتار كاتاليزوردر همو پليمريزاسيون    اتيلن تحت كنترل داشت. و با انجام پيش پليمريزاسيون به خواص پليمر و مورفولوژي مورد نظر رسيد و    شرايط را بهبود بخشيد.

در اين مطالعه كاتاليست نيكل-آهن بر پايه آلومينا در ريفرمينگ خشك متان در ميكرو راكتورها به منظور بررسي نحوه عملكرد كاتاليست و دستييابي به نقطه بهينه كاتاليست انجام گرفته است. 

  Abstract Investigating and studying the flow characteristics at the confluence of the rivers has been one of the topics discussed in the last decade, where the region is known as the one with high turbulence and three-dimensional motion. Due to changes in the amount and direction of velocity, flow rate and sediment discharge, phenomena such as bed erosion and bank erosion occur. The sepration zone immediately forms a junction down stream and causes flow contraction. which this leads to an increase in velocity and thus to bed erosion. In addition, the resulting vortex flow creates problems for shipping. Therefore, numerous field and laboratory studies have been done to investigate the pattern of flow and sediment conditions at the confluence. These studies have investigated the effects of various parameters such as the discharge ratio, Froude number, and the angle of junction on the hydraulic conditions of the flow. However, no significant studies have been done to reduce the velocity and decrease the dimensions of the separation zone at the open channels junction. The present study aims at investigating the effect of nonsubmerged guide walls on the separation region and velocity variations. Firstly, a numerical model was written utilizing the flow3d software, which, according to the previous studies, was verified. Then, the effects of the guide walls on the junction flow pattern were investigated. In addition, the effect of the guide walls on decreasing dimensions or removing the separation zone as well as the velocity reduction at the open channel junctio   were investigated. The results showed that the application of the guide wall decreases the velocity at the open channel junction. Also, in models where the wall was spaced b/2 (b is the width of channels) from the inner wall of the main channel, the separation zone was not omitted, but its length was reduced. And in models with wall b/4 spaced from the inner wall of the main channel, the separation zone was removed.

  In this study, the catalyst of Mn-Na2WO4/H-ZSM-5 with the percentage of 2% and 5% for Mn and Na2WO4 used as co catalyst in the process of oxidation coupling of methane fabricated. Selectivity, methane conversion and yield process were analyzed in several temperatures. The H_ZSM5 using as support, fabricated using hydrothermal method. The SEM, TGA and EDX were used to analyze catalyst properties. The results of experiments show that the selectivity was improved by 53%, the methane conversion reached 51% and the yield process of C2 reached 27% at 800 C.

Solar water splitting in the absence of sacrificial agent has been identified as a promising approach to produce green hydrogen. In this work, for the first time we report the photocatalytic activity of BiFeO3/g-C3N4 composite in hydrogen production. For this purpose we synthesized various BiFeO3/g-C3N4 composite samples with different mass ratio of g-C3N4 and investigated the as-prepared photocatalysts activity for hydrogen production during the overall water splitting reaction.The composite samples exhibits remarkably enhanced photocatalytic performance in comparison with the bare BiFeO3 and g-C3N4. The highest hydrogen production rate obtained is ? 160.75 µmol. h-1. g-1 under UV irradiation ( ? ? 250 nm) and ?23.31   µmol/h-1 g-1 under visible light irradiation ( ? ? 400 nm). This enhanced photocatalytic activity of BiFeO3/g-C3N4 heterojunction should be attributed to the synergistic effect of junction and the complementary advantages between BiFeO3 and g-C3N4, which can efficiently accelerate the separation of photogenerated electron-hole pairs and also capability to perform water reduction and oxidation reaction simultaneously.  

     In this study, MoO3 metal oxide was loaded by mechanical and wet impregnation methods on nano structure g-C3N and SBA-15 supports, respectively. After finding the optimum amounts of metal oxide loading, 10%MoO3/g-C3N4 and 5%MoO3/SBA-15 nano catalysts were used in the oxidative desulfurization (ODS) process. For investigation the performance of the synthesized nano catalysts in the ODS process, Dibenzothiophene (DBT), H2O2, and acetonitrile were selected respectively   as the target compound in 1000ppm model oil, oxidant, and solvent. In order to optimize the operating conditions including temperature, amount of catalyst, H2O2/DBT molar ratio and time reaction, Response surface methodology based on Box-Behnken Design of Expert (DOE) software was applied for each nano catalyst. Among the various models, DOE proposed the Quadratic equation model because of good accordance with experimental data for each catalysts (R-Squared=0.9831%, Adj R-Squared=0.9707 for 5%MoO3/SBA-15 and R-Squared=0.9569%, Adj R-Squared=0.9240 for 10%MoO3/g-C3N4, respectively). The results of optimization for 5%MoO3/SBA-15 nano catalyst were T=55 ?C, 0.02g amount of catalyst, H2O2/DBT=9 and 49 min reaction time and for 10%MoO3/g-C3N4 nano catalyst optimum condition were T=70 ?C, 0.04g amount of catalyst, H2O2/DBT=8.44 within 55min reaction time. The efficiency of the 5% MoO3/SBA-15 and 10% MoO3/g-C3N4 nano catalysts were predicted to be 100% and 97.7% in optimal operating conditions, respectively.     To evaluate the performance of the synthesized nano catalysts in the removal of other sulfur compounds in the optimal conditions expressed by DOE, two other model oils, 1000ppm Benzothiophene (BT) and Thiophene (Th), were applied in the ODS process, and the   removal efficiency of sulfur compounds was in order of   DBT > BT > Th. Also, the regeneration of the nano catalysts was evaluated four times, showing yield decreases of 5% and 6% for 5%MoO3/SBA-15 and 10% MoO3/g-C3N4, respectively. Finally, the performance of the   ano catalysts in the removal of sulfur compounds of gasoline and gas oil from the Kermanshah Oil Refining & Distribution Company was investigated, and the obtained efficiencies of sulfur removal were 69.73% and 49% for 5%MoO3/SBA-15   and 58.35% and 41% for 10%MoO3/g-C3N4 respectively.

  The photocatalytic CO2 reduction has attracted more attention owing to the increasing global energy crisis and environmental contamination. In this work, BaTiO3 nanoparticles decorated with Fe2O3 nanoparticles were successfully prepared by hydrothermal method for efficient visible-light photocatalytic CO2 reduction, and successfully characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), FT-IR spectroscopy, UV-visible and photoluminescence spectroscopy (PL) techniques. UV-visible and PL analyses showed the higher response of composites, in visible region and higher efficiency of charge separation, respectively. The FESEM illustrated the well crystalline particles of BaTiO3 and Fe2O3, and the BF31 (BaTiO3:Fe2O3 with 3:1 molar ratio) image shows a good dispersal of BaTiO3 and Fe2O3. Compared to bare BaTiO3, Fe2O3 and other different molar ratio composites, the BF31 composite photocatalysts exhibited strongest enhanced photocatalytic CO2 reduction activity under visible light irradiation. The photodegradation percentage of CO2 for BF31 composite could reach 22%, which was much higher than those of bare BaTiO3, Fe2O3 and other different molar ratio composite samples. The enhanced photocatalytic CO2 reduction activity could be attributed to the formation of heterojunction at the interface between BaTiO3 and Fe2O3 in the composite, which would facilitate the photo-generated electron-hole separation and thus improve the photocatalytic activity.

Recently, in the oil and refining industry, due to improving product quality and the decrease of environmental pollution, purification of fossil fuels from sulfur compounds is very important. Therefor, in this study we investigated performance of ZSM-5 supported molybdenum oxide catalyst in oxidative desulfurization. The main purpose of this research is study of support structure, molybdenum loading and operating conditions. we synthesized   ZSM-5 by two different methods, direct and seed silicate-1 by varying the Si/Al molar ratio at a constant Mo concentration of 3wt%.   The catalysts were characterized by XRD, N2-physisorption, FT-IR, FESEM. Our results indicated that   3% molybdenum oxide  upported  on ZSM-5 with Si/Al molar ratio of 15 and 20 compared to other catalysts are very active in oxidative desulfurization .The conversion percentage of these catalysts are nearly%80.Then,we investigated a series of zeolite supported molybdenum  oxide catalysts with Mo loading ranging from 3 to 15 wt% and Si/Al molar ratio of 15,20. Among Synthesized catalysts 6% molybdenum oxide  upported  on ZSM-5(15) and 10% molybdenum oxide  upported  on ZSM-5(20) have a high performance. eventually, 6% molybdenum oxide  upported  on ZSM-5(15) was investigated by Box-Behnken design. The Box-Behnken design showed that the optimum values for the conversion of DBT were 67?C (oxidation temperature), 0/04g (catalystamount),8 (O/S molar ratio) and 41/78 (Reaction time)   respectively. In addition, the catalyst shows excellent reusing ability. The results shawed slight decrease in performance of catalyst after four times regeneration.   

  Global warming and excessive greenhouse gas of concern for todays world has become a dangerous consequences such as drought, diseases, fire and leads. One of these gases is carbon dioxide, which for the separation there of the different ways. One of these methods is using photocatalyst, especially MOFs as a new class. In this study, Prvfyryn- based on metal-organic framework (Co / PMOF) is Using Tetrakis ((4- carboxy phenyl Prvfyryn (TCPP)is built as a ligand, And is analysis by spectrum FESEM and EDX. Photocatalytic experiments around (Co / PMOF) as a photocatalyst is done in the presence of water as a sacrificial electron donor under irradiation with visible / UV.   Results from the reaction shows that mol10 . 96µmol methane is produced in about 4 hours response, which indicates is the high level of production. In addition to measuring the UV-vis and FTIR spectra show that there is no sign of change in the structure of photocatalyst. As well as the reaction mechanism has been studied.

  Advanced oxidation process (AOPs) are being considered because of more efficiency and none second pollution, and are used for remove of diverse pollutant such organic materials, textile dyes, heavy metals and etc. In this research efficiency of photocatalytic advanced oxidation process has investigated color removal of methylene blue fom synthetic sewage by using photocatalyst of BiOCl-ZnO As modified with CTAB and PEG20000 surfactant in a photoreactor. So has devoted The comparison between the two types of surfactants with pure photocatalyst (at the time of synthesis catalyst), characters and efficiency and photocatalyst activity in color removal methylene blue should be investigated and evaluated. Solution concentration, pH and dosage of photocatalyst were evaluated. XRD, SEM, FTIR and DRS analysis were used for both the properties of pure and modified with surfactant and In the whole experiment the criteria of system performance efficiency was spectrophotometery method color removal yield. In sem Images of two types of photocatalysts synthesized with surfactant, It can be seen that Photocatalyst surface is More homogeneous. The results of DRS indicate the positive impact of PEG surfactant in photocatalytic performance in the visible region. X-ray diffraction (XRD) pattern of the BiOCl-ZnO exhibit typical diffraction peaks corresponding to the hexagonal structured ZnO that suitable agreement to literature value (JCPDS card no.80-0075) and the tetragonal phase BiOCl (JCPDS card number 06-0249), respectively. FTIR spectra indicate the presence of elements and related connection. Laboratory optimum condition for the maximum dye removal of methylene blue was found 1g BiOCl-ZnO PEG20000, pH=9.5 and solution concentration 20 ppm.

In this research, photocatalytic degradatio   of aqueous ammonia by Ag doped ZnO under visible light was investigated. The experiments were done under visible light irradiation in an appropriate liquid phase batch reactor. Spectroscopy analysis was used for measuring the concentration of ammonia and produced compounds. The performance of prepared photocatalyst and photoreactor was studied by 26 separate experiments in some condition such as initial solution pH, initial ammonia concentration, catalyst dosage and visible light intensity) as well as their interactions were determined on the removal of NH4+/NH3 by mentioned method. FTIR, SEM, XRD and UV-Vis analysis were used to i  ect specification of prepared photocatalyst. Analysis of the experimental results confirms Ag-doping improve both photoadsorption and photoactivity of Ag doped ZnO under visible light irradiation. Finally, Optimum experimental conditions were found at   ammonia primary concentration=170 ppm, lamp power=250W and pH=11.  

Mercaptans, sulfides and disulfides are compounds that exist in fossil fuels, which creates disadvantages such as odor, corrosion and reduce the fuel heating value. In the present study, adsorptive Demercaptanization of condensate via modified activated carbon by concentrated nitric acid and then loaded with silver and copper metal ions and also, silver metal ions loaded copper-benzene three carboxylate (Cu-BTC) metal-organic framework were examined. Condensate with mercaptan content of 188 ppm was purchased from Fajr Jam Gas Refinery. The mercaptan content of samples was measured by titration method. After adsorption experiments, adsorption isotherms correlation parameters for Langmuir and Freundlich models and kinetic parameters for pseudo-first-order and pseudo-second-order kinetic models were studied. In this study, Cu-BTC adsorbent shows a good absorption performance in adsorption of mercaptan compounds from gas condensates. The maximum adsorption capacity for Ag loaded Cu-BTC and treated and then Ag and Cu loaded activated carbon were obtained 49.416 mg/g and 4.824 mg/g respectively. Also, the SEM, XRD, EDX and FT-IR tests were used to approve the structure of Cu-BTC MOF, metal loading confirmation, absorbent surface morphology, crystal structure of absorbent and the adsorbent structure stability.