Dissertations / Theses on the topic 'Ammonia separation'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 23 dissertations / theses for your research on the topic 'Ammonia separation.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
Pengilley, Christine. "Membranes for gas separation." Thesis, University of Bath, 2016. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.678858.
Full textErasmus, Mothobi. "Leaching of nickel laterite with a solution of ammonia and ammonium carbonate utilizing solids liquid separation under pressure." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20091.
Full textAFRIKAANSE OPSOMMING: Logingstoetse van saprolitiese lateriet met 'n oplossing van ammonia en ammonium karbonaat is gedoen in 'n druk houer. Die logingsvat vir hierdie studie is ontwikkel om die loging sowel as die vloeistof – vastestof skeiding te doen. Gesinterde metaal filter medium was gebruik vir die vloeistof – vastestof skeiding aangesien dit die volgende eienskappe vertoon; die vermoë om druk te weerstaan, die chemiese weerstand teen bytsoda oplossing, asook voordelige terugspoel eienskappe. Optimum loogkondisies is bepaal deur die temperatuur, ammoniak konsentrasie, ammonium karbonaat konsentrasie, en suurstof druk te varieer. Na loging en filtrasie is die pH van die loogvloeistof gemeet en monsters is deur atoom absorpsie spektrofotometrie geanaliseer vir opgeloste metale (Ni, Fe en Co). Die veranderlike wat die grootste effek op die loging van nikkel gehad het was die ammoniak konsentrasie. Die maksimum herwinning van nikkel van uit ongeroosterde erts was 11.9 % by 4 M NH3, 100 oC, 2 M (NH4)2CO3 en 2 bar O2 druk. Optimisering van die loogdata is gedoen deur die respons profiel te analiseer met Statistica sagteware. Optimum loogkondisies was bepaal as 3 M NH3, 2 M (NH4)2CO2, 100 oC en 2 bar O2 druk. Die mineralogie van die erts voor en na loging is bestudeer om te bepaal waarom die nikel opbrengs van ongeroosterde erts so laag was. XRF analise van die vastestof na loging het gewys dat yster, silikon en magnesium nie deur loging affekteer is nie. Slegs nikkel het 'n merkwaardige afname getoon. XRD analsiese van die vastestof voor en na loging wys dat die meeste mineraal fases teenwoordig in die erts nie deur die loogoplossing affekteer is nie. SEM met EDS deteksie is gebruik om die nikkel verspreiding in die erts te bepaal. Die resultate wys dat nikkel meestal met yster assosieer. Die yster is omring deur magnesium en silikon. Silikaat minerale reageer nie met ammoniak en ammonium karbonaat oplossing nie. In filtrasie eksperimente is daar gevind dat die filtrasie differensiële druk geen noemenswaardige effek op die filtrasie tempo gehad het nie. Die gemiddelde filtrasietempo was 0.29+0.07 ml/min.cm2. Die filtrasie tempo van hierdie eksperimente was baie laag, hoofsaaklik as gevolg van blokkasie van porieë van die sinter metaal filter medium. Dit is gevind dat blokkasie van porieë hoofsaaklik op die oppervlak van die filter medium plaasvind. Lateriedes toon 'n lae deurlaatbaarheid as gevolg van die erts se hoë klei inhoud. Rheologiese studies op hierdie erts wys dat die erts skuif verdikking (“shear thickening”) gedrag vertoon. 'n Baie helder filtraat is egter verkry. Die gesinterde metale is na elke loog en filtrasie eksperiment skoongemaak deur terugspoeling met water en lug. Hierdie procedure was suksesvol, aangesien al 18 eksperimente met dieselfde filter medium uitgevoer is. Die effek van erts roostering voor loging is ondersoek by die optimum kondisies wat verkry was vir die loging van ongeroosterde erts. Nikkel ekstraksie het effens verbeter met geroosterde erts. Die gemiddelde persentasie ekstraksie van nikkel van drie eksperimentele lopies was 19.25 % + 0.19 by 100 oC, 3 M NH3, 2 M (NH4)2CO3, en 5 bar suurstofdruk. 'n Gedeelte van die nikkel in die erts was onherwinbaar as gevolg van die assosiasie van nikkel met her-gekristaliseerde sillikaat-minerale in die gereduseerde erts. Die porositeit van die erts is verbeter deur dit te rooster. Die filtrasie tempo het merkwaardig verbeter nadat die erts gerooster is. Die gemiddelde filtrasie tempo was 2.6+0.05 ml/min.cm2. Kinetika vir die oplossing van ongeroosterde en geroosterde saprolitiese lateriet is ondersoek, met in ag geneem die effekte van temperatuur, ammonia konsentrasie, ammonium karbonaat konsentrasie en suurstofdruk. Vir ongeroosterde erts is gevind dat die oplossingstempo en graad van nikkel ekstraksie toeneem met toenemende temperatuur. Toename in ammoniak konsentrasie lei tot 'n toename in nikkel ekstraksie, maar nikkel ekstraksie is nie alleenlik afhanklik van ammoniak nie. 'n Toename in ammonium karbonaat konsentrasie lei ook tot 'n toename in nikkel ekstraksie. Ammonium karbonaat is krities vir die ekstraksie, aangesien ammonium ione in die oplossing die hidrolise van die nikkel-amien kompleks verhoed. Suurstof het nie 'n merkwaardige effek op die totale nikkel ekstraksie gehad nie. Vir die bepaling van reaksie kinetika is 100˚C gebruik as die logingstemperatuur. Die loging van saprolitiese nikkel lateriet vind in twee stadia plaas. In die eerste fase is die oplossing van nikkel vinnig, maar na 15 minute neem die reaksietempo af. Die reaksietempo word verlaag deur inerte minerale wat teenwoordig is in die nikkel erts. Hierdie minerale bevat yster, magnesium en silikon. Die vinnige oplossing van nikkel in die eerste fase verteenwoordig die loging van vry nikkel in die erts. Die data vir die tweede stadium is geanaliseer deur die krimpende kern model, en die resultate dui aan dat die oplossingstempo deur 'n gemengde meganisme beheer word (as laag diffusie en oppervlak reaksie beheer). Die aktiveringsengergie vir die oplossingsreaksie was bereken as 56.5 kJ/mol. Die reaksieorde ten opsigte van ammoniak en ammonium karbonaat is onderskeidelik bepaal as 0.3 en 0.26. Die hoogste graad van nikkel ekstraksie vir die geroosterde erts is verkry by 60oC, 3 M NH3, 2 M (NH4)2CO3, en 5 bar O2 druk. Die persentasie ekstraksie by hierdie kondisies was 28.7 %. Temperatuur het nie 'n merkwaardige effek op loogtempo gehad nie. 'n Toename in NH3 en (NH4)2CO3 het die graad van nikkel ekstraksie laat toeneem, maar het nie enige effek op die loogtempo gehad nie. In die afwesigheid van ammonium karbonaat het byna geen nikkel ekstraksie plaasgevind nie. Die eksperimentele data het nie 'n lineêre passing vir die krimpende kern model soos vir die ongeroosterde erts ondersoek gegee nie. Die rede hiervoor is dat die monsternemings interval te groot was, of dat die logings karakteristiek van geroosterde nikel gekompliseerd is en nie alleen deur die krimpende kern model voorspel kan word nie. Logings eksperimente wys dat die temperatuur hoog moet wees (> 100 oC) om 'n hoë graad van nikkel ekstraksie te verkry met die ongeroosterde erts. 'n Geslote reaktor word benodig om by 'n hoë temperatuur met ammoniak en ammonium karbonaat te loog om reagens verliese te verhoed. Die reaksie kinetika word grootliks deur aslaag diffusie beheer. Hieruit kan gesien word dat 'n lae graad van nikkel ekstraksie uit die ongeroosterde saprolitiese lateriet die gevolg is van nie-reaktiewe minerale (aslaag) waarin die nikkel binne die erts bevat word. Om 'n hoë graad van nikkel ekstraksie te verkry moet die erts onder reduserende kondisies gerooster word. Rooster kondisies moet versigtig beheer word om hoë oplossing van nikkel te verseker. Optimum rooster kondisies om maksimum nikkel oplossing te verkry, moet bepaal word voordat daar met groter hoeveelhede erts gewerk kan word.
Liman, Martin. "Výměna hmoty kapalina-pára v procesech stripování." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-445374.
Full textSilva, Rafael Gundim. "Remoção de amônia do lixiviado por arraste de ar e caracterização por fracionamento com membrana." Universidade do Estado do Rio de Janeiro, 2011. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=8614.
Full textThe proposal of present work is to study the technology for removing ammonia from leachate by physico-chemical process of air stripping and its characterization after fractionation processes with MF and UF membranes. Were analyzed the process of entrainment of air pH, air flow rate and operating time. Moreover, there was the removal of ammonia nitrogen from 93.5% in a running time of 6 hours, with pH adjustment equal to 11 and air flow rate 100 L / h. Soon after the first treatment the leachate were characterized in the process of fractionation with membranes (MF and UF) and were investigated the remotion of ammonia, conductivity, COD, COD, chloride and pH. Getting results were nearly constant as the leachate permeated the membranes of MF and UF. Moreover, were employed for toxicity tests and biological treatability tests on samples of raw leachate, leachate treatment group (low ammonia concentration) and leachates fractionated with the MF and UF membranes. In tests of biological treatability results showed no significant removal of organic matter and toxicity tests with organisms Danio rerio, besides the occurrence of a reduction in toxicity, it was found that the raw leachate, leachate treated with removal of ammonia and fractionated with the MF and UF membranes maintained high values of toxicity.
Rambocus, Subhas. "Reactive solvent extraction of dicarboxylic and carboxylic-sulfonic acids." Thesis, London South Bank University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245144.
Full textGustavsson, Hanna. "Opportunities for increased nutrient recovery at centralised wastewater treatment plants through urine separation." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-440801.
Full textAwobusuyi, Tolulope David. "Concentration of Ammonium from Dilute Aqueous Solutions using Commercially Available Reverse Osmosis Membranes." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34642.
Full textBrunson, Kennard. "POLYURETHANE-BASED POLYMER SURFACE MODIFIERS WITH ALKYL AMMONIUM CO-POLYOXETANE SOFT BLOCKS: REACTION ENGINEERING, SURFACE MORPHOLOGY AND ANTIMICROBIAL BEHAVIOR." VCU Scholars Compass, 2010. http://scholarscompass.vcu.edu/etd/2258.
Full textNzeadibe, Kingsley C. I. "Synthesis of new, single-isomer quaternary ammonium derivatives of beta-cyclodextrin for electrophoretic enantiomer separations." Texas A&M University, 2003. http://hdl.handle.net/1969.1/5833.
Full textAdusumilli, Harika. "Separation and identification of peptides by integrated multidimensional liquid chromatography-mass spectrometry (IMDLC-MS)." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/6028.
Full textThe entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 15, 2008) Vita. Includes bibliographical references.
Kabangu, Mpinga John. "Extraction and separation of tantalum and niobium from Mozambican tantalite by solvent extraction in the ammonium bifluoride-octanol system." Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/25313.
Full textDissertation (MSc)--University of Pretoria, 2012.
Chemical Engineering
unrestricted
Wills, Peter. "Novel biocidal formulation." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/novel-biocidal-formulation(776ed624-6717-496f-9b31-ad2edce8e24b).html.
Full textRodriguez, Machine Carla Thais. "Raman spectroscopic study of CO2 capture and separation by semi-clathrate hydrates crystallization and investigation of exchange processes in hydrates." Electronic Thesis or Diss., Université de Lille (2018-2021), 2021. http://www.theses.fr/2021LILUR003.
Full textNowadays, fossil fuels are constantly burnt to fulfill the increasing human and industrial demand in energy, and as a consequence, large quantities of greenhouse gases such as carbon dioxide (CO2) are released in the atmosphere and contribute to global warming. It is therefore pressing to develop efficient post-combustion CO2 mitigation techniques that are also efficient and environment-friendly, and as such, Carbon Capture and Storage (CCS) technologies involving the Hydrate-Based Separation Process (HBSP) have attracted a lot of attention. HBSP consists in encapsulating small gas molecules (e.g. CO2, nitrogen (N2), methane (CH4)) within crystalline ice-like compounds known as clathrate hydrates or hydrates. Previous works have shown that promoters like tetra-n-butyl ammonium bromide (TBAB) considerably improves the guest-gas trapping mechanism in semi-clathrate hydrate (sc). Hence, while HBSP proves to be a suitable technique for selective CO2 capture and energy recovery, advancing the fundamental understanding of processes at play is still needed before large-scale practical applications can be routinely considered. This work aims to better comprehend CO2 separation and capture processes using sc-hydrate technology, while also exploring exchange processes in hydrates to open a perspective towards industrial applications.First, the guest distribution in the hydrate phases of CO2¬-based clathrate hydrates as a function of parameters (initial composition, p, T) is revisited and elucidated by ex-situ high-resolution Raman spectroscopy. Up to now, there is a gap in the literature regarding the discrimination of the contribution of the small and large cages in CO2-based hydrates, mainly due to the Fermi resonance effect. So far, only a single study has attempted to distinguish these contributions in CO2-clathrates, however with a questionable interpretation. One of the novelties of the present work is to revisit the vibrational properties of CO2-clathrates to identify distinct frequency shifts depending on the structural environment of CO2 molecules, thereby improving our knowledge of CO2 encapsulation mechanisms in hydrates. High-resolution Raman analysis and neutron diffraction analyses are additionally performed in CO2-based TBAB-semi-clathrates for characterization purposes.Second, the influence of two different formation protocols (quick and slow crystallization protocols, commonly used in hydrate formation) on the encapsulation mechanisms, the structure, and the selectivity of CO2+N2-TBAB compounds is investigated by in-situ Raman spectroscopy. A new dissociation point (pressure and temperature) is obtained and our results highlight that slow hydrates formation rates exert a variable performance on CO2 selectivity at temperatures far from the dissociation point, while a better performance is observed when approaching dissociation. Similarly, separation factors reach their greatest values close to the dissociation, depending however on the sc crystal structure formed. Surface morphology variation is monitored by optical microscopy and exhibits a continuous transformation with temperature, starting from a rough surface coated with polygonal or stacked shaped crystals to the formation of columnar TBAB-sc crystals near dissociation. Moreover, the influence of the formation kinetics on CO2 separation and selectivity is explored.Finally, a potential application of CO2 separation and capture by HBSP is addressed through the investigation of the exchange mechanism when exposing CO2 clathrate hydrates to N2 gas. Even though CO2 and N2 hydrates crystallize in structure sI and sII, respectively, it is a CO2-N2 mixed hydrate with a preferential occupation of the small cages by N2 molecules that forms upon N2 injection. The exchange kinetics is analyzed from the perspective of methane recovery from CO2 and CO2+N2 injections
Lamirault, Sylvie. "Comportement du cuivre dans les melanges hf-mf (m = k ou nh : :(4)) fondus utilises pour l'obtention electrolytique du fluor." Paris 6, 1987. http://www.theses.fr/1987PA066467.
Full textJoly, Jean-Pierre. "Synthèse d'éthers-couronnes osidiques et leur fixation sur support chromatographique en vue de la séparation d'énantiomères." Nancy 1, 1989. http://www.theses.fr/1989NAN10019.
Full textZHAN, ZHI-JIE, and 詹志潔. "Emulsion liquid-membrane separation technology and its application in ammonia removal from dilute aqueous solution." Thesis, 1987. http://ndltd.ncl.edu.tw/handle/92704279436678503404.
Full textHuang, Pei-Fang, and 黃珮芳. "Mixed matrix membrane consisting HIPS copolymer and porous ZIF-8 crystals for gas separation: Ammonia-assisted synthesis of ZIF-8 crystals in micro-aqueous solution." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/20957027177818651629.
Full text國立中興大學
環境工程學系所
104
Mixed matrix membranes (MMMs) consisting of organic and inorganic phase was raised much attention due to its mechanical strength, thermal ability, and good permselectivity compared to polymer membrane. However, the separation performance of MMMs was influenced by the dispersion of inorganic and the interfacial adhesion between the organic and inorganic phase. Therefore, the choice of suitable materials and the applicable methods to synthesis a defect-free MMMs with good performance have been discussed in the recent works. In this study, the symmetric and asymmetric MMMs were prepared by incorporated ZIF-8 as filler. In the design of green procedure, ZIF-8 crystals were synthesized at the minimum stoichiometric ratio of Zn : Hmim = 1 : 2 with micro-aqueous solution. The ammonia was added as a catalyst to assist in the growth of ZIF-8 crystal. To examine the effect of molar ratio of NH4+ = 0.22-0.42 mol on the morphology and pore arrangement of ZIF-8. Further, the separation performance of MMMs was evaluated by single gas permeation test at different feed pressure. The results indicated that the ZIF-8 crystals can be synthesized by micro-aqueous solution with different NH4+/DIW ratio. Increasing with the molar ratio of NH4+/DIW is benefit to the grain growth of ZIF-8 crystal as well as the improvement of ZIF-8 pore structure development, such as total pore volume and surface area. Moreover, the ZIF-8 fillers have a well adhesion to the organic phase, which effectively increased the gas separation performance of polymer membrane. The CO2 and O2 permeability increased from 16.39 Barrer to 20.89 Barrer and 4.32 Barrer to 5.88 Barrer, respectively. The selectivity of CO2/N2 and O2/N2 reached to 18.43 and 5.77, respectively when adding 10 wt% ZIF-8. Moreover, the addition of ZIF-8 could avoid to the CO2-induced plasticization phenomena of membrane in gas permeation. Thus, CO2/N2 separation performance of MMMs was improved by the additive ZIF-8 at high feeding pressure. However, O2/N2 selectivity of MMMs was not significantly influenced at high permeability due to the pore size of ZIF-8 was not benefit to the transport of O2 and N2 molecules.
MAIEROVÁ, Monika. "Porovnání vybraných metod výpočtu základního odtoku na malém povodí a zhodnocení vlivu základního odtoku na koncentrace dusíku v celkovém odtoku." Master's thesis, 2013. http://www.nusl.cz/ntk/nusl-154482.
Full textWarmadewanthi, I. D. A. A., and 娃瑪. "Selective Separation of Phosphate, Fluoride and Ammonium from Semiconductor Wastewater." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/69607887027114742755.
Full text國立臺灣科技大學
化學工程系
97
Selective separation of phosphate and ammonium from fluoride-containing wastewater of semiconductor manufacturing was studied utilizing magnesium salts. The characteristics of raw wastewater influence the treatment process. In the presence of excess NH4, simultaneous separation of phosphate and ammonium as struvite (MgNH4PO4.6H2O) was investigated. Magnesium chloride (MgCl2.6H2O) was used as precipitation reagent. When at molar ratio ([Mg]:[PO4]) of 2.5:1 and pH 9, total of 84.2% of phosphate and 33.5 % of ammonium were removed. Addition of excess ammonium was beneficial for struvite precipitation, as revealed from experimental results and model prediction. Characterization of solid precipitates using X-ray diffraction (XRD) confirmed the presence of struvite, and other minerals mostly bobierrite ((Mg)3(PO4)2.8H2O). When at lower concentration of ammonium and phosphate, results showed that MgCl2 is a better selective precipitation reagent compared with MgO. In the first stage, total of 41.72 % of phosphate was recovered at molar ratio ([Mg]:[PO4]) of 3:2 and pH 10. Recovery of phosphate increased with increasing molar ratio, and 66.12% of phosphate was recovered when molar ratio ([Mg]:[PO4]) was 3:1. Recovery of phosphate increased as pH increased from 8 to 10. However, it decreased as pH further increased to 12. Solid precipitates in range pH of 8 to 10 were dominantly bobierrite and some amorphous precipitates. Results in this study showed that fluoride and sulfate did not affect precipitation reactions. In the second stage, CaCl2 was used to induce precipitation of calcium fluoride and calcium phosphate. Residual fluoride concentration at pH 10 was 9.9 mg/L. Sodium dodecylsulfate (SDS) was an effective collector for subsequent solid-liquid removal via dispersed air flotation. Theoretical equilibria were modeled with PHREEQC and compared with experimental results. The advantages of selective separation of phosphate, ammonium and fluoride include recovery of struvite and bobierrite as reusable minerals, better control of dosing systems, and higher separation efficiency.
黃章霖. "Analysis and Improvement of Ammonium Sulfate Separation and Recovery System." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/04936800882401813525.
Full textLiu, Hsueh-Ying, and 劉學穎. "Separation of homologues of quternary ammonium surfactants by capillary electrophoresis with indirect UV detection." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/31435510596050834003.
Full text國立中央大學
化學研究所
91
Abstract This investigation describes the simultaneous separation of two major non-chromophoric quaternary ammonium surfactants, alkytrimethyl and dialkydimethyl ammonium compounds ( ATMACs and DADMACs, respectively ), by capillary electrophoresis ( CE ) with indirect UV detection. The most effective separation condition was 10 mM phosphate buffer with 57.5% tetrahydrofuran and 3 mM SDS at pH 4.35, and the sample hydrodynamic injection of up to 20 sec at 1 psi ( approximately 59.33 nL ), and an applied voltage 25 kV. The selection of appropriate chromophore and internal standard to improve the peak identification and quantitation was systematically investigated. Decylbenzyldimethyl ammonium chloride ( C10-BDMAC ) as a chromophore wih 3 mM SDS provided the best detectability for all homologues. The reproducibility of the migration time and quantitative analysis can be improved by using tetraoctylammonium bromide ( TOA+B- ) as an internal standard, giving the relative standard deviation ( RSD ) less than 0.8% for the relative migration times, and 2.5 to 5.5% for the relative peak areas. A good linearity of CE analysis was obtained in the range of 1.0 to 2.0 μg/mL with r2 values of above 0.999. The analysis of cationic surfactants in commercial products of hair conditioners and fabric softeners was also performed. Electrospray mass spectrometric method ( ESI-MS ) was applied to evaluate the CE method , and the compatible results were obtained.
Ahmadloo, Farid, Gwyn Mali, Antonin Chapoy, and Bahman Tohidi. "GAS SEPARATION AND STORAGE USING SEMI-CLATHRATE HYDRATES." 2008. http://hdl.handle.net/2429/1386.
Full textLiao, Jhen-Hua, and 廖振驊. "Experimental and simulation study of vacuum and direct contact membrane distillation for separating ethanol/water and ammonia/water solutions." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/56549150911289110312.
Full text中原大學
化學工程研究所
100
In ethanol fermentation, the major limitation of the continuous process comes from product inhibition, generally inhibition becoming important as ethanol concentration greater than 10 wt % . The integration of a fermenter with membrane distillation has been investigated as a tool for the continuous removal of ethanol from fermentation broths. In addition, membrane distillation has received attention in recent years for the removal of volatile compounds like ammonia for recycling and reuse of industrial wastewater, especially for which has a relatively low level of ammonia. In this study, simulation and experiments are carried out in the study to analyze the effects of operating conditions on the performances of ethanol and ammonia removal from aqueous streams by membrane distillation. Direct contact membrane distillation(DCMD) and vacuum membrane distillation(VMD) two different membrane distillation processes are considered in the study. Comparison between the simulation result in the study and the experimental data from literatures of VMD ammonia separation showed that simulation analysis with considering free ammonia (FA) factor is better to estimate selectivity of ammonia. Simulation showed that the selectivity of ammonia increases with the vacuumed pressured of the permeated side and the pH of the solution in the pH range of 9~11. Under some conditions given in the study, high ammonia selectivity up to 11 is estimated. Experimental results of DCMD with feed of 5~ 15 wt% ethanol and at 40 oC showed that 0.12μm PTFE membrane gives an ethanol enrichment factor 20~40 % higher than that by 0.45 μm PTFE membrane. As the feed temperature and ethanol concentration increase, ethanol flux increases as a result, while lower ethanol enrichment factors are obtained. It is noted that the PVDF membrane will be wetted when the feed has a higher ethanol concentration as 15 wt % . Comparison between the simulation and the measured fluxes in DCMD showed that the effect of interaction between water and ethanol molecules on effective diffusivity of water can be ignored in calculation of water flux. However, the model with considering the interaction between the two molecules will give a better result in simulation of ethanol flux . Experimental and simulation results at the given conditions of 50~60 oC and 5~15 wt % ethanol concentration showed that ethanol flux and ethanol enrichment factor of VMD are higher than the DCMD operation. But, when the feed temperature is at 40 oC and concentration of 10 ~ 15wt%, the DCMD will produce a higher enrichment factor for ethanol. Simulation results of membranes in the pore size range of 0.01~0.2 m showed that the use of membranes with smaller pore size can enhance the selectivity of the ethanol in DCMD. However, the membrane pore size can only give a slight effect on the ethanol enrichment factor under the conditions given in the study.