نتایج جستجو برای: modified zeolite
تعداد نتایج: 258999 فیلتر نتایج به سال:
در این کار پزوهشی نانوکامپوزیت های zno/go، zno/zeolite و zno/go/zeolite تهیه شد و فعالیت فوتوکاتالیستی آن ها در حذف پارانیتروفنل از آب آلوده مورد بررسی قرار گرفت. بدین منظور، ابتدا نانوذرات zno به روش سل ژل و با کمک ژل طبیعی متشکل از نشاسته و سیتریک اسید تهیه شد. نانوکامپوزیت های zno/go به دو روش عامل دار کردن سطح با استفاده از سمی کاربازید هیدروکلرید و ssd تهیه شدند. سپس نانوکامپوزیت های zno/z...
در این پروژه نانوکامپوزیت fe3o4/nay zeolite با ترکیب درصدهای متفاوت تهیه و فعالیت کاتالیزوری آن ها در واکنش استری شدن جهت تعیین بهترین ترکیب درصد مورد بررسی قرار گرفت. در ادامه از بهترین ترکیب درصد کامپوزیت fe3o4/nay zeoliteبرای تهیه کامپوزیت fe3o4/nay zeolite/mcm-41 استفاده شد. سپس این کامپوزیت ها توسط روش های tga, sem, xrd, ft-ir و vsm مورد بررسی قرار گرفتند. در واکنش استری شدن تاثیر عو...
نانو ذرات tio2 وzno و zeolite با استفاده از روش سل - ژل و تحت تابش اولتراسونیک تهیه می شود. سپس نانو کامپوزیت zno/zeolite/tio2 به وسیله استفاده از روش سونوشیمیایی به روش سل - ژل تهیه شده و سل های آنها با یکدیگر مخلوط می-شود. سل اولیه اکسید روی از محلول ، استات روی zn(ch3coo) 2 ، آمونیاک، nh3 ، اتانول تهیه می شود . پیش ماده ، تیتانیم تتراایزوپروپوکسید (ttip) c16h36o4tiرا در اتانول حل کرده ، به آ...
Mesoporous aggregates of nanocrystalline zeolites with MFI and BEA frameworks have been synthesized using a one-pot and single structure directing agent. The effect of different reaction conditions, such as temperature, time, pH and water content, on the particle size, surface area and mesopore volume has been studied. Nanocrystalline and mesoporous ZSM-5, β and Y zeolites were modified with di...
A control thick-film SnO2 gas sensor was modified with zeolites holding LTA, FAU and MFI frameworks using two different approaches to integrate them into the gas-sensing interface. The objective was to prompt selectivity and sensitivity enhancements that were otherwise unattained with the unmodified material when detecting a range of hydrocarbon vapours with similar molecular structures and kin...
Abstract: Â In this study adiffusion based mathematical model was developed to compare the performance of amine-grafted adsorbents with that of 13X zeolite in a fixed-bed adsorption tower which is used to capture CO2 from both humid and dry nitrogen stream under industrial conditions. The results show that the performance of amine-grafted adsorbent and 13X zeolite is almost the same in the dry ...
Ce-ZSM-11 Zeolite: An Efficient Heterogeneous Catalyst for One-Pot Synthesis of 4H-Pyran Derivatives
ZSM-11 zeolite was synthesized by hydrothermal treatment and cerium ion was incorporated by the ion exchange method. The catalytic activity of cerium modified ZSM-11 zeolite was tested for the one-pot synthesis of 4H-pyran derivatives by cyclocondensation of aromatic aldehyde, malononitrile, and ethyl acetoacetate. The synthesized catalyst was characterized by Po...
The potassium (K) sorption characteristics with three adsorbents, natural zeolite, ammonium acetate-treated and manganese nodule, were studied compared to see the potential use of nodule as an alternative K adsorbent. In general, Langmuir isotherm could fit in KCl solutions at different pH conditions better than Freundlich isotherm. Based on parameters, maximum was greater for zeolite-based ads...
Natural zeolites are abundant and inexpensive resources. They crystalline hydrated aluminosilicates with a framework structure that has pores channels occupied by water, alkali, alkaline earth cations. Having high cation exchange capacity, acting as molecular sieve, natural have been widely utilized in recent decades adsorbents separation purification processes. Modification of zeolite increase...
in this research, adsorption of dibenzothiophene (dbt) as a model of sulfur containing material has been studied by pb exchanged y-zeolite under different experimental conditions. the adsorption was kinetically fast and high adsorption capacity was obtained. the equilibrium adsorption data were analyzed using langmuir and freunlich isotherm models. the corresponding parameters and correlation c...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید