Molecular sieve Puns

I had an idea which requires molecular sieve material to serve as a barrier between a water based solution and air. I believe diatomic oxygen is around 3 angstrom which is similar to H20. Do only the surfaces of molecular sieves do the capturing or is it permeable?

I dont have access to dry sieves at temps higher than 200C. Will drying under vac over night at 200 suffice to dry 3A sieves?

Hi

So I have order 1kg of molecular sieves directly from the factory in China (via Aliexpress) which I want to use to get 96%ethanol to higher purity. The thing I am wondering is whether the molecular sieves might release poisonous substances. In principle they should not be poisonous as they are made of zeolite but I am not sure whether poisonous substances or heavy metals etc. are used for the production.

Does somebody have an answer or can tell me how to make sure that they are safe to use. I thought of maybe 'using' them several times on distilled water as to wash out any poisonous substances. Might this work?

Thanks in advance!

After watching a caffeine extraction video, which is very similar to spice extraction, I wondered if sieves might be useful for drying solvent. In the video, after their saline wash, they dried it with sieves. Any chance this is viable, or would it soak up spice?

My assumption is that spice is larger than 3Å, but if anyone has any info on whether these have been tested or not would be nice.

If not I guess the classic Anhydrous Sodium Sulfate is still tried and true.

The global Zeolite Molecular Sieve Market size is expected to value at USD 4.27 billion by 2022. The zeolite molecular sieve industry is subject to witness a substantial growth due to the rising demand for production of detergent and catalysts. Additionally, zeolite molecular sieve is increasingly utilized as an absorbent due to of its sieve-like structure. Zeolite molecular sieve are crucial for separation and adsorption in various manufacturing process for production of detergents.

Zeolite molecular sieve used as an absorbent, particularly in oil & gas sector and for water treatment. Rising demand for detergents due to increase in hygiene awareness among consumers is anticipated to boost demand for zeolite molecular sieve as a builder in liquid and powder detergents. Globally, the zeolite molecular sieve market is predicted to grow at CAGR of 2.3% in the forecast period, providing numerous opportunities for market players to invest for research and development in the market.

Download Sample Report @ Zeolite Molecular Sieve Market

Rapid expansion of oil & gas industry, particularly in the North America & South America region, and end-use demand for catalysts to provide higher yield are estimated to aggravate market growth over the next seven years. In addition, substantial increase in the number of water treatment activities for wastewater treatment and purification of water are propelling market demand for zeolite molecular sieve, in the recent years.

However, availability of various alternatives such as enzymes, metals and other chemical compounds and their relatively lower cost in comparison with zeolite molecular sieve are expected to limit market demand to a certain extent. Additionally, volatility in cost of raw materials is restraining market growth, in the last few years. Yet, introduction of silver infused sieves as an antimicrobial is expected to amplify market expansion in the near future.

Zeolites, which are micro-porous in nature and contains alumino-silicate minerals are commonly used as industrial adsorbents and catalysts. Zeolites are naturally found compounds. However, zeolites are manufactured for industrial use on a large scale. Industrially important zeolites are manufactured via various synthetic technique. Industrial zeolites are produced by heat

So 190 proof is impossible for me to get but I can get 151 everclear and wanna use some zeolite 3a to absorb the water out of it to increase the proof now would I need zeolite powder or the beads? Any info would help out greatly also I’m doing this to use the higher proof Ethanol as a solvent not to drink

Low-cost 3 Å zeolite was used to sieve the excess solvents within Li-ion solvation sheaths of typical carbonate electrolyte to eliminate the adverse effects (high-voltage/temperature oxidation, unstable CEI/SEI). As a result, high-voltage lithium-metal battery (LMB) that used this zeolite sieved electrolyte demonstrated a significantly improved cycling time and safety, but largely reduced production cost.

Abstract

As one typical clean-energy technologies, lithium-metal batteries, especially high-energy-density batteries which use concentrated electrolytes hold promising prospect for the development of a sustainable world. However, concentrated electrolytes with aggregative configurations were achieved at the expense of using extra dose of costly and environmental-unfriendly salts/additives, which casts a shadow over the development of a sustainable world. Herein, without using any expensive salts/additives, we employed commercially-available low-cost and environmental-friendly molecular sieves (zeolite) to sieve the solvation sheath of lithium ions of classic commercialized electrolyte (LiPF6-EC/DMC), and resulting in a unique zeolite sieved electrolyte which was more aggregative than conventional concentrated electrolytes. Inspiringly, the new-designed electrolyte exhibited largely enhanced anti-oxidation stability under high-voltage (4.6 volts) and elevated temperature (55 °C). NCM-811//Li cells assembled with this electrolyte delivered ultra-stable rechargeabilities (over 1000 cycles for half-cell; 300 cycles for pouch-cell). More importantly, sustainable NCM-811//Li pouch-cell with negligible capacity decay can also be obtained through using recyclable zeolite sieved electrolyte. This conceptually-new way in preparing safe and highly-efficient electrolyte by using low-price molecular sieve would accelerate the development of high-energy-density lithium-ion/lithium-metal batteries.

https://ift.tt/3sFdPp2

Hi all, I have been investigating some ways to remove water (as vapor) during a reflux under N2. The water is a byproduct and I am a bit worried it may hydrolyze ether chains. Solvent is DMF.

I found an article that showed a column packed with molecular sieves under the condenser like in this article: https://pubs.acs.org/doi/10.1021/acs.joc.9b01541 and am considering copying it. It looks like I have the right glassware in my lab, but the reflux will continue for a few days based on similar synthesis literature and I am unsure if the majority of the water will form quickly or not.

Another option I am considering is measuring out the right amount of drying sodium sulfate and keeping it in the distilling flask, but the product is a polymer and I fear the salt will get into the precipitate and be too difficult to remove.

Any other suggestions? Thanks in advance

Hi yall, currently doing a capstone and we need to simulate some molecular sieves on Aspen Hysys however I couldnt find any packages for that, is there any detailed packages I may have missed?

Non‐zeolitic‐pores were successfully embedded inside a microporous MFI type zeolite membrane. The resulting hierarchical structure was beneficial for achieving robust, high p‐xylene separation performance.

Abstract

MFI type zeolites with 10‐membered‐ring pores (ca. 0.55 nm) have the ability to separate p‐xylene (ca. 0.58 nm) from its bulkier isomers. Here, we introduced non‐zeolitic micropores (ca. 0.6–1.5 nm) and mesopores (ca. 2–7 nm) to a conventional microporous MFI type zeolite membrane, yielding an unprecedented hierarchical membrane structure. The uniform, embedded non‐zeolitic pores decreased defect formation considerably and facilitated molecular transport, resulting in high p‐xylene perm‐selectivity and molar flux. Specifically, compared to a conventional, crack network‐containing MFI membranes of similar thickness (ca. 1 μm), the mesoporous MFI membranes showed almost double p‐xylene permeance (ca. 1.6±0.4×10−7 mol m−2 s−1 Pa−1) and a high p‐/o‐xylene separation factor (ca. 53.8±7.3 vs. 3.5±0.5 in the conventional MFI membrane) at 225 °C. The embedded non‐zeolitic pores allowed for decreasing the separation performance degradation, which was apparently related to coke formation.

https://ift.tt/3iEPjiz

Journal of the American Chemical SocietyDOI: 10.1021/jacs.0c09433

Hiroki Nagasawa, Takahiko Kagawa, Takuji Noborio, Masakoto Kanezashi, Atsushi Ogata, and Toshinori Tsuru

https://ift.tt/2MkqP3R

Wikipedia did not give clear result for "molecular valve", which is slightly strange.

In really small scales, making mechanical valves is hard. Molecular valve could be seen - kind of - as valve without moving parts, or at least parts that are not placed based on resolution.

Green and efficient synthesis of titanium‐containing molecular sieves is limited by large amount of environmentally unfriendly additives and complicated synthesis procedures necessarily required to avoid the oligomerization of Ti monomers to anatase TiO 2 , due to a mismatch between hydrolysis rates of Si and Ti precursors. Here, we report a simple and generic additive‐free route for the synthesis of Ti‐containing molecular sieves (MFI, MEL, and BEA). This approach successfully reverses the Ti oligomers formation to match hydrolysis rates of Ti and Si species with the assistance of hydroxyl free radicals generated in‐situ from ultraviolet irradiation. Moreover, fantastic catalytic performance for propene epoxidation with H 2 and O 2 is observed. Compared with the conventional hydrothermal method, this approach opens up new opportunities for high‐efficiency, environmentally‐benign, and easy‐operating production of pure titanium‐containing molecular sieves.

https://ift.tt/35L1Ahj

Carbon molecular sieve (CMS) membranes show exceptional separation performance and scalable processing attributes attractive for important, similar‐sized gas pairs. A mathematical and physical framework to understand these attributes is presented.

Abstract

Demand for energy‐efficient gas separations exists across many industrial processes, and membranes can aid in meeting this demand. Carbon molecular sieve (CMS) membranes show exceptional separation performance and scalable processing attributes attractive for important, similar‐sized gas pairs. Herein, we outline a mathematical and physical framework to understand these attributes. This framework shares features with dual‐mode transport theory for glassy polymers; however, physical connections to CMS model parameters differ from glassy polymer cases. We present evidence in CMS membranes for a large volume fraction of microporous domains characterized by Langmuir sorption in local equilibrium with a minority continuous phase described by Henry's law sorption. Using this framework, expressions are provided to relate measurable parameters for sorption and transport in CMS materials. We also outline a mechanism for formation of these environments and suggest future model refinements.

https://ift.tt/2YOY1o4

I'm making system to remove trace moisture and contaminants from the compressed air coming from a 5 cfm compressor, and decided molecular sieves would be needed to get things as dry as possible. To keep energy consumption high, I figured it would be interesting to use a heat pump to regenerate the sieves.

The problem is that the 4A seives I'm using need to be heated to >250C to release all their moisture, so the working fluid has to function at 300C. As a side note, does anyone know of any standard (ish) hermetic refrigeration compressors that would tolerate fluid temperatures in that range, even if just under light load and good cooling?

Water is the most important and universal substance in nature. People have been striving to pursue and discover water‐related processes and imitate these important discoveries for the benefit of mankind. As a successful example of human imitating the formation of natural materials, molecular sieves have been synthesized under hydrothermal condition and applied in industry. Herein, we reveal an unforeseen observation on a very special water‐induced structural dynamic process of these materials. Dynamic and reversible breakage‐bonding of T‐O‐T bonds in silicoaluminophosphate (SAPO) occurs due to interactions between gaseous water and molecular sieve framework under mild hydrothermal conditions and is confirmed by successful detection of the incorporation of 17 O from H 2 17 O into molecular sieve framework. Successfully encapsulation of bulky molecules trimethylphosphine and pyridine (kinetic diameters much larger than the pore size of SAPO‐34) into CHA cavities consolidated the water‐induced dynamic process. Consequently, new insights into the dynamic features of molecular sieve in the atmosphere of water are provided. The ship‐in‐a‐bottle strategy based on these findings also open new fields for fine acidity identification and give extra boost in shape‐selective catalysis.

https://ift.tt/2OTR2Ep

As one typical clean‐energy technologies, lithium‐metal batteries, especially high‐energy‐density batteries which use concentrated electrolytes hold promising prospect for the development of a sustainable world. However, concentrated electrolytes with aggregative configurations were achieved at the expense of using extra dose of costly and environmental‐unfriendly salts/additives, which casts a shadow over the development of a sustainable world. Herein, without using any expensive salts/additives, we employed commercially‐available low‐cost and environmental‐friendly molecular sieves (zeolite) to sieve the solvation sheath of lithium‐ions of classic commercialized electrolyte (LiPF 6 ‐EC/DMC), and resulting in a unique zeolite sieved electrolyte which was more aggregative than conventional concentrated electrolytes. Inspiringly, the new‐designed electrolyte exhibited largely enhanced anti‐oxidation stability under high‐voltage (4.6 volts) and elevated temperature (55 o C). NCM‐811//Li cells assembled with this electrolyte delivered ultra‐stable rechargeabilities (over 1000 cycles for half‐cell; 300 cycles for pouch‐cell). More importantly, sustainable NCM‐811//Li pouch‐cell with negligible capacity decay can also be obtained through using recyclable zeolite sieved electrolyte. This conceptually‐new way in preparing safe and highly‐efficient electrolyte by using low‐price molecular sieve would accelerate the development of high‐energy‐density lithium‐ion/lithium‐metal batteries.

https://ift.tt/3sFdPp2

Non‐zeolitic‐pores were successfully embedded inside a microporous MFI type zeolite membrane. The resulting hierarchical structure was beneficial for achieving robust, high p‐xylene separation performance.

Abstract

MFI type zeolites with 10‐membered‐ring pores (ca. 0.55 nm) have the ability to separate p‐xylene (ca. 0.58 nm) from its bulkier isomers. Here, we introduced non‐zeolitic micropores (ca. 0.6–1.5 nm) and mesopores (ca. 2–7 nm) to a conventional microporous MFI type zeolite membrane, yielding an unprecedented hierarchical membrane structure. The uniform, embedded non‐zeolitic pores decreased defect formation considerably and facilitated molecular transport, resulting in high p‐xylene perm‐selectivity and molar flux. Specifically, compared to a conventional, crack network‐containing MFI membranes of similar thickness (ca. 1 μm), the mesoporous MFI membranes showed almost double p‐xylene permeance (ca. 1.6±0.4×10−7 mol m−2 s−1 Pa−1) and a high p‐/o‐xylene separation factor (ca. 53.8±7.3 vs. 3.5±0.5 in the conventional MFI membrane) at 225 °C. The embedded non‐zeolitic pores allowed for decreasing the separation performance degradation, which was apparently related to coke formation.

https://ift.tt/3iEPjiz

Demand for energy‐efficient gas separations exists across many industrial processes, and membranes can aid in meeting this demand. Carbon molecular sieve (CMS) membranes show exceptional separation performance and scalable processing attributes attractive for important, similar‐sized gas pairs. Herein, we outline a mathematical and physical framework to understand these attributes. This framework shares features with dual‐mode transport theory for glassy polymers; however, physical connections to CMS model parameters differ from glassy polymer cases. We present evidence in CMS membranes for a large volume fraction of microporous domains characterized by Langmuir sorption in local equilibrium with a minority continuous phase described by Henry’s law sorption. Using this framework, expressions are provided to relate measurable parameters for sorption and transport in CMS materials. We also outline a mechanism for formation of these environments and suggest future model refinements.

https://ift.tt/2YOY1o4