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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
401

Efeito do laser de baixa potência associado ao uso de feltro ativado no processo de reparo ósseo em tíbia de ratos

Foster, Fernando Gredinare 17 December 2016 (has links)
Submitted by Nadir Basilio (nadirsb@uninove.br) on 2018-06-18T19:03:08Z No. of bitstreams: 1 Fernando Gredinare Foster.pdf: 984670 bytes, checksum: afea175c4e00ac9803bd6bdda1570d7d (MD5) / Made available in DSpace on 2018-06-18T19:03:08Z (GMT). No. of bitstreams: 1 Fernando Gredinare Foster.pdf: 984670 bytes, checksum: afea175c4e00ac9803bd6bdda1570d7d (MD5) Previous issue date: 2016-12-17 / The bone defects are caused by several factors and the repair process can be slow, where inflammatory and proliferative phases of remodeling of this tissue are extremely important for the quality of the repair. There are several therapies where the main is the surgery and in this case, the use of bone substitutes can be indicated. However the repair process may require assistance. Thus, the use of activated charcoal as bone substitute when the implementation of low-power laser to aid bone repair can be an alternative to these problems. The aim of this study was to verify the use of activated carbon felt as bone substitute and the interaction with the laser in the process of bone repair in rat tibias, assessing biochemical, histological and biomechanical changes. Material and methods: male wistar rats, 35 were used between 150 g to 200 g, with 3 months of age. The animals were anesthetized with ketamine hydrochloride and Association (90mg/Kg and 10mg/Kg, IP). Once anesthetized, the animals were put on surgical table, the skin was dissected and were made monocortical bone defects in the central region of the right tibia of mice. Immediately after surgery the rats were randomized and divided into the following groups: control (CTL), untreated Injury (NT), Lesion treated with activated carbon felt (AF), Lesion treated with lasertherapy (L6J) and Lesion treated with association of activated carbon felt and laser 830nm, 6J-100mW (AF+L). After 28 days the animals were euthanized with overdose of the same anesthetic, blood was collected and the tibia was taken for biochemical, histological and biomechanical analysis. Committee of ethics: AN00462014-UNINOVE. Results: the NT group reduction in bending forces and histological changes related to disorganization of the tissue. The group showed no L improve mechanical properties, whereas AF increase the strain in compare to CTL. AF+L group presented better flexion forces, related with improvement of histological aspects, however increased the alkaline phosphatase levels. Conclusion: the use of activated carbon felt seems to improve the bone repair induced in this study. The laser association with activated carbon felt showed improvement of biomechanical properties and still the histological results have a better aspect. / Lesões ósseas são difíceis de serem tratadas e dependendo do grau da lesão, a intervenção cirúrgica é um dos tratamentos utilizados. Neste caso, o uso de substitutos ósseos pode ser necessário. A terapia com laser de baixa potência tqmbém é indicada como terapia auxiliar, pela sua importante ação analgésica e de reparo. Porém, pouco se sabe a respeito da interação entre biomateriais e laserterapia. O objetivo deste trabalho foi verificar o uso do feltro ativado como substituto ósseo e a interação com a laserterapia de baixa potência no processo de reparo ósseo em tíbias de ratos, analisando aspectos histológicos, bioquímicos e biomecânicos. Material e Métodos: Foram utilizados 35 ratos wistar, entre 150g à 200g, com 3 meses de idade. Depois de anestesiados, os animais foram colocados em mesa cirúrgica, a pele foi dissecada e o defeito ósseo monocortical foi confeccionado na região central da tíbia direita dos animais. Imediatamente após a cirurgia os ratos foram randomizados e organizados nos seguintes grupos: Controle (CTL), Lesão não tratado (NT), Lesão tratado com feltro ativado (AF), Lesão tratado com Laser (L6J) e Lesão tratado com associação do feltro ativado e laser 830nm, 6J – 100mW (AF+L). Após 28 dias os animais foram eutanasiados, o sangue foi coletado e a tíbia removida para análises histológicas e biomecânicas. Resultados: O grupo NT apresentou redução do reparo ósseo traduzido pela baixa organização histológica e redução da resistência mecânica. O grupo AF apresentou aumento da capacidade de deformação enquanto que o grupo L apresentou melhor organização histológica. O grupo AF+L apresentou melhora na resistência mecânica. Concluímos que o laser associado ao uso do feltro de carbono ativado auxiliou o reparo ósseo no modelo de lesão em tíbia de ratos.
402

An Investigation of Market Scalability for Volatile Organic Compounds (VOCs') Filtration Systems : A Case Study within Sweden

Kurukundu, Chaitanya Sai Praneeth, Gajjala, Anvesh Reddy January 2020 (has links)
With the need for excellent living standards to escalate day by day, the need to breathe good quality air remains of paramount importance for a prosperous, happy life. The indoor air quality picture is improving decade by decade. However, the importance of maintaining good indoor air quality remains unsatisfactory. Indoor air quality is one of the world’s most significant environmental problems. Statistics states that as of 2017, approximately 1.6 million premature deaths are caused by bad indoor air quality. The majority of these deaths result from the presence of Volatile Organic compounds in the air. VOCs are the common pollutants that are found indoors, which are not only toxic but also dangerous to health on long exposures. Even though several norms are put in place, why is the picture still persistent even after many technological advancements in the industry? This notion of this idea inspired the authors to conduct the current thesis. The thesis is based on a case study at a Swedish Air-cleantech company, Company-X, that developed efficient air filtration technologies to eliminate VOCs from the indoor air. However, for efficient diffusion of the technology, studying the market is of utmost importance. For this, the study is done by qualitative interviewing of professionals from the Swedish air filtration market. The interactions helped the authors to comprehend the more in-depth picture of influencing facets in persistent VOC issues in the indoor airs. Secondly,the meetings guided the authors with the industry choice for efficient technologies to eliminate VOCs from the indoor air. The collected data led to the conclusions that, various actors like awareness and buying decision factors, technologies are involved for VOCs still being a persistent issue in indoor airs. The industry’s awareness regarding Volatile Organic Compounds has been mediocre, and the significant factor for the buying decision is the price. Speaking of the technology, it has been reckoned that Activated Carbon filters are the best and economically efficient technology to eliminated VOCs from the air.
403

Utvärdering av effektivitet för aktivt kol och anjonbytare vid reduktion av per- och polyfluorerade alkylsubstanser (PFAS) samt läkemedelssubstanser i avloppsvatten

Kalecinska, Monika January 2021 (has links)
Avloppsreningsverk (ARV) utgör en viktig del som spridningsväg för utsläpp av organiska mikroföroreningar, som per- och polyfluorerade alkylsubstanser (PFAS) och läkemedelssubstanser, från samhället till den akvatiska miljön. Befintliga reningssteg vid ARV reducerar mikroföroreningar dåligt varav denna studie syftade till att jämföra reduktionseffektiviteten av 5 olika granulära aktiva kol (GAK) och en anjonbytare (AIX) för att välja ut det material som är mest lämpat för vidare undersökningar i pilotskala inför installation ett avancerat reningssteg i Kungsängsverkets ARV i Uppsala. GAK (Filtrasorb 400, Cyclecarb 401, Brennsorb 1240, Aquasorb 5000 och Aquasorb 2000) utvärderades för avskiljning av 13 PFAS-ämnen i ett inledande bägarförsök genom placering i avloppsvatten från Kungsängsverket i 8 h. Cyclecarb 401 var mest effektivt vid avskiljning av PFAS där reduktionsgraden för PFAS-11 (85 %) och PFOS (90 %) var 35 % och 40 % högre än för det minst effektiva GAK Brennsorb 1240. Cyclecarb 401, Brennsorb 1240 och AIX Purolite 694E undersöktes i ett andra bägarförsök enligt en liknande metod, men utvärderades med avseende på avskiljning av 12 PFAS och 18 läkemedelssubstanser över 48 h. Resultatet för PFAS var likvärdigt för GAK, men AIX visades nå samma reduktionsgrad av PFAS som Cyclecarb 401 och detta skedde snabbare. Efter 48 h var reduktionen med GAK högst för läkemedelssubstanser (91-99 %) och med AIX för PFAS (78 %). Samtliga adsorbenter tillfördes även till kolonner, där Purolite 694E även seriekopplades efter Cyclecarb 401, med ett kontinuerligt flöde av avloppsvatten motsvarande 5 min kontakttid (EBCT). Även om duplikatprover togs varje vecka genomfördes inom ramen för detta examensarbete analyser för de prover tagna en timme (12 bäddvolymer), 2 veckor (4000 bäddvolymer) och 7 veckor (14 000 bäddvolymer) efter start för 12 PFAS och 18 läkemedelssubstanser. Purolite 694E reducerade PFAS bäst, 40-50 % bättre än GAK, följt av negativt laddade läkemedelssubstanser och adsorptionen för dessa ämnen var bättre över tid än för GAK. Seriekoppling av AIX efter GAK förbättrade reduktionsgraden över tid för främst PFAS (30 % ökning vid 14 000 bäddvolymer). Även för läkemedelssubstanser med negativ laddning som adsorberades väl av AIX. Adsorptionen till AIX gynnades mest av substanser med negativa laddning. Adsorptionen till samtliga adsorbenter gynnades av PFAS med en sulfonatgrupp, en lägre syrakonstant, en högre fördelningskonstant mellan oktanol och vatten samt en längre kolkedja. En seriekoppling av AIX efter GAK är främst intressant för förbättrad avkiljning av diklofenak och PFOS vid Kungsängsverket, men även avskiljning av andra PFAS och negativt laddade läkemedelssubstanser kan förbättras. Andra ämnen adsorberades väl av GAK där Cyclecarb 401 i samtliga försök visats mest effektiv. De analyserade provpunkterna för kolonnförsöket var för få varav en kommande noggrannare undersökning över hela försökets genomförande kommer påvisa livslängderna för varje adsorbent vid EBCT 5 min. EBCT var kort varav efterföljande försök bör undersöka avskiljningens effektivitet för Kungsängsverket vid längre EBCT. / Waste water treatment plants (WWTPs) constitute an important role in releasing organic micropollutants, such as per- and polyfluoroalkyl substances (PFAS) and pharmaceuticals, from the society into the aquatic environment. Reduction of them in existing treatment methods in WWTPs is insufficient which is why the aim of this study was to examine the reduction efficiency for 5 granular activated carbons (GAC) and an anion exchange resin (AIX) and choose the adsorbent most suited for further studies in pilot scale before an advanced treatment step is built to Kungsängsverket WWTP in Uppsala.  GAC (Filtrasorb 400, Cyclecarb 401, Brennsorb 1240, Aquasorb 5000 and Aquasorb 2000) were evaluated for 13 PFAS compounds in an initial batch experiment using wastewater from Kungsängsverket during 8 h. Cyclecarb 401 had the highest removal efficiency for PFAS where the reduction grade for PFAS-11 (85 %) and PFOS (90 %) was 35 % and 40 % higher than for the least efficient GAC Brennsorb 1240. Cyclecarb 401, Brennsorb 1240 and the AIX Purolite 694E were evaluated in a second batch experiment through a similar method, analyzed for 12 PFAS and 18 pharmaceuticals over 48 h. The results for PFAS were similar for GAC, but AIX reached the same reduction grade for PFAS as Cyclecarb 401 which also happened faster. After 48 h reduction with GAC was best for pharmaceuticals (91-99 %) and with AIX for PFAS (78 %). Finally, these adsorbents were placed in individual columns, where Cyclecarb 401 was connected to an additional column with Purolite 694E, with a continuous flow of wastewater with an empty bed contact time (EBCT) of 5 min. Even though duplicate samples were taken each week analysis was performed for samples taken an hour (12 bed volumes), 2 weeks (4000 bed volumes) and 7 weeks after start (14 000 bed volumes) for 12 PFAS and 18 pharmaceuticals. Purolite 694E reduced PFAS the best, 40-50 % better than GAC, followed by negatively charged pharmaceuticals and adsorption for these compounds was better over time than with GAC. AIX after GAC increased reduction grade over time primarily for PFAS (30 % improvement after 14 000 bed volumes) but also for pharmaceuticals well adsorbed by AIX. Adsorption to AIX was mainly improved with a negative charge of the compound. Adsorption to adsorbents was favored for PFAS containing a sulfonate group, compounds with a lower acid dissociation constant, a higher octanol-water partition coefficient and a longer carbon chain. Implementation of AIX after GAC would be of interest for Kungsängsverket mainly due to the improved removal of diclofenac and PFOS, but also if removal of other PFAS and pharmaceuticals will become prioritized. Other compounds were removed by GAC well where Cyclecarb 401 was most effective in all experiments. The analyzed samples for the column experiment were too few which is why a more comprehensive study of all samples over the whole experiment period will be able to determine the life length of each adsorbent for EBCT 5 min. EBCT was short which is why further experiments need to examine the reduction efficiency for Kungsängsverket at a longer EBCT.
404

Sledování účinnosti odstraňování pesticidů ze zdrojů pitné vody vybranými adsorbenty / Monitoring the effectiveness of removing pesticides from drinking water sources by selected adsorbents

Gottwald, Martin January 2019 (has links)
In the introductory part of this diploma thesis the pesticidal substances and their legislative requirements in drinking water are described. This is followed by a description of technologies in which pesticides can be removed and used in water treatment plants. In the practical part of the thesis is described description of the experimental procedure of the removal of pesticides on two selected adsorption materials (Filtrasorb F100 and Bayoxide E33) and subsequently this experiment is evaluated.
405

Sledování účinnosti odstraňování léčiva z vody vybranými adsorbenty / Monitoring drug removal efficiency from water by selected adsorbents

Moravčíková, Světlana January 2020 (has links)
This diploma thesis deals with the efficiency of removal of pharmaceuticals from drinking water by selected adsorption materials. The first part describes sources of pharmaceuticals in drinking water and possible ways of contaminating water by pharmaceuticals. Subsequently, the pharmaceuticals most commonly found in the environment - nonsteroidal anti-inflammatory drugs, antibiotics, psychiatric drugs and sex hormones - are described in more detail. Next, the thesis describes the processes used for removal of pharmaceuticals. These are activated carbon adsorption, membrane processes and advanced oxidation processes. The last chapter of the theoretical part of the thesis deals with water treatment plants, where the technologies for removing drugs are already in operation. In the practical part of this thesis an experiment was performed and evaluated, for a purpose of comparing the efficiency of selected sorption materials in the removal of diclofenac from water. Filtrasorb F100, Bayoxide E33 and GEH were used.
406

Využití biouhlí jako sorpčního materiálu pro odstranění syntetických vonných látek z vod / The use of biochar as a sorption material for the removal of synthetic fragrances from water

Kašparová, Jarmila January 2020 (has links)
Synthetic fragrances (musk) are artificially produced organic compounds. It is used as fragrance ingredient in personal care products. Substances from this group have the ability to withstand the cleaning process in wastewater treatment plants. The physico-chemical properties of musk compounds cause their accumulation in the living and non-living components of the ecosystem, where they behave as persistent pollutants. The adsorption process is considered to be one of the most widely used separation and purification processes. The adsorption processes of a solution of sixteen synthetic fragrances took place with biochar and activated carbon. Solid phase microextraction (SPME) was used as a method for extracting analytes. Gas chromatography coupled with mass spectrometry (GC-MS) was applied for final analysis, time of flight analyzer was used as detector. The data were fitted with adsorption isotherms.
407

Čištění bioplynu pomocí metody PSA (adsorpce za měnícího se tlaku) / Cleaning of biogas by the PSA (pressure swing adsorption)

Navrátil, Petr January 2014 (has links)
The topic of this master thesis is upgrading of biogas. As a mixture of gases produced during anaerobic digestion, contains methane which is highly energy valuable gas. But also other substances that we want to remove. We will present the motivation for upgrading biogas and the possibility of separation, generally the pressure swing adsorption method. The key parameter of this technique is the choice of a suitable adsorbent. This is possible based on the knowledge of adsorption processes, therefore, is also described below. The objective of this thesis is to determine the parameters of the pressure swing adsorption metod. To do this it is necessary to determine the adsorption capacity of the adsorbent, measure breakthrough curves of carbon dioxide and methane, and determine the pressure drop of solid bed, etc. As a result we can finally make a balance and evaluate the applicability in practice.
408

Sledování pesticidních látek ve zdroji úpravny vody Hrdibořice a možnost jejich odstranění / Monitoring of pesticides in source of water treatment Hrdibořice and possibility of their removal

Bouchalová, Zuzana January 2017 (has links)
The thesis discusses possible ways to reduce or completely eliminate pesticide compounds from drinking water that are produced at a water treatment plant Hrdibořice. The work is divided into theoretical and practical parts. The theoretical part lists kinds of pesticides that occur in water, how they are reduced or eliminated. Furthermore, this section describes the existing water treatment technologies at the Central Committee Hrdibořice, including water sources. In the practical part, pilot tests on two types of filters models with filtering bed of granular activated carbon (hereinafter GAU) were carried out. On the basis of information obtained from the literature and on findings from the pilot tests, designs of technological equipment for pesticide removal from drinking water at water treatment Hrdiborice were carried out. Next, cost estimates for the proposed variant solutions including operating costs were suggested.
409

Ispitivanje uticaja odabranih amida na adsorpciju nitro derivata fenola iz vodene sredine na aktivnom uglju / Investigation of selected amide influence on adsorption of nitro derivatives of phenol on activated carbon from water

Kordić Branko 18 September 2019 (has links)
<p>U&nbsp; radu&nbsp; je&nbsp; ispitan&nbsp; uticaj&nbsp; amida&nbsp; kao&nbsp; modela&nbsp; AOM-a (Algalne organske materije)&nbsp; na adsorpciju nitrofenola iz vodene&nbsp; sredine&nbsp; na&nbsp; aktivnom&nbsp; uglju.&nbsp; Istraţivanje&nbsp; se sastojalo&nbsp; iz&nbsp; tri&nbsp; faze:&nbsp; ispitivanje&nbsp; uticaja&nbsp; karateristika amida&nbsp; na&nbsp; adsorpciju&nbsp; nitrofenola,&nbsp; ispitivanje&nbsp; uticaja granulacije na adsorpciju nitrofenola u prisustvu amida i ispitvanje karakterisitka samih nitrofenola na adsorpciju u&nbsp; prisustvu&nbsp; amida.&nbsp; Pre&nbsp; ispitivanja&nbsp; adsorpcije&nbsp; u dvokomponentnim&nbsp; sistemima&nbsp; ispitana&nbsp; je&nbsp; adsorpcija jednokomponentnih&nbsp; sistema&nbsp; 4-nitrofenola,&nbsp; 2,4-dinitrofenola&nbsp; i&nbsp; 2,4,6-trinitrofenola,&nbsp; kao&nbsp; i&nbsp; amida&nbsp; Nmetilbenzamid,&nbsp; nikotinamida&nbsp; i&nbsp; N-benzilbenzamida&nbsp; na komercijalnim&nbsp; aktivnim&nbsp; ugljevima&nbsp; NORIT&nbsp; SA2&nbsp; i&nbsp; dve granulacije&nbsp; aktivnog&nbsp; uglja&nbsp; DARCO.&nbsp; Aktivni&nbsp; ugljevi&nbsp; su ispitani&nbsp; metodom&nbsp; FTIR&nbsp; spektroskopije,&nbsp; SEM&nbsp; analizom, analizom&nbsp; povr&scaron;ine&nbsp; adsorpcijom&nbsp; azota&nbsp; na&nbsp; niskoj temperaturi&nbsp; i&nbsp; određivanjem&nbsp; taĉke&nbsp; nultog&nbsp; naelektrisanja. Urađena&nbsp; je&nbsp; geometrijska&nbsp; optimizacija&nbsp; modela&nbsp; molekula ispitivanih nitrofenola i amida i izraĉunati su molekulski parametri.&nbsp; Uticaj&nbsp; amida&nbsp; kao&nbsp; modela&nbsp; AOM-a&nbsp; je&nbsp; ispitan kori&scaron;ćenjem&nbsp; razliĉitih&nbsp; ravnotežnih&nbsp; i&nbsp; difuzionih adsorpcionih&nbsp; modela.&nbsp; Kao&nbsp; kriterijum&nbsp; za&nbsp; određivanje najsporije&nbsp; adsorpcione&nbsp; faze&nbsp; kori&scaron;ćen&nbsp; je&nbsp; Biotov&nbsp; broj.<br />Adsorpcioni&nbsp; parametri&nbsp; dobijeni&nbsp; u&nbsp; eksperimentima&nbsp; sa dvokomponentnim&nbsp; sistemima&nbsp; su&nbsp; upoređivani&nbsp; sa parametrima dobijenim za adsorpciju samih nitrofenola.</p> / <p>In this research influence of selected amides, as a model of&nbsp; AOM&nbsp; (Algal&nbsp; organic&nbsp; matter),&nbsp; on&nbsp; adsorption&nbsp; of nitrophenols&nbsp; from&nbsp; water&nbsp; on&nbsp; activated&nbsp; carbon&nbsp; has&nbsp; been<br />investigated.&nbsp; Research&nbsp; is&nbsp; divided&nbsp; in&nbsp; three&nbsp; phases: investigation&nbsp; of&nbsp; influence&nbsp; of&nbsp; amide&nbsp; molecule characteristics&nbsp; on&nbsp; the&nbsp; adsorption&nbsp; of&nbsp; nitrophenols, investigation&nbsp; of&nbsp; granulation&nbsp; influence&nbsp; on&nbsp; nitrophenol adsorption in&nbsp; the&nbsp; presence of amide and investigation of nitrophenol characteristics that can influence adsorption in&nbsp; the&nbsp; presence&nbsp; of&nbsp; amides.&nbsp; Adsorption&nbsp; of&nbsp; nitrophenols and&nbsp; amides&nbsp; in&nbsp; single- component&nbsp; systems&nbsp; has&nbsp; also&nbsp; been carried&nbsp; out.&nbsp; Adsorption&nbsp; kinetics&nbsp; of&nbsp; 4-nitrophenol,&nbsp; 2,4-dinitrophenol,&nbsp; 2,4,6-trinitrophenol,&nbsp; N-methylbenzamide,<br />nicotinamide&nbsp; and&nbsp; N-benzylbenzamide&nbsp; has&nbsp; also&nbsp; been investigated. Commercial activated carbons NORIT SA2 and&nbsp; two&nbsp; granulations&nbsp; of&nbsp; DARCO&nbsp; were&nbsp; used.&nbsp; Activated carbons&nbsp; were&nbsp; characterized&nbsp; using&nbsp; FTIR&nbsp; spectroscopy, SEM&nbsp; analysis,&nbsp; internal&nbsp; surface&nbsp; analysis&nbsp; using&nbsp; nitrogen adsorption&nbsp; on&nbsp; low&nbsp; temperature&nbsp; and&nbsp; determination&nbsp; of point&nbsp; of&nbsp; zero&nbsp; charge.&nbsp; Geometry&nbsp; optimization&nbsp; of nitrophenol&nbsp; and&nbsp; amide&nbsp; molecules&nbsp; has&nbsp; been&nbsp; carried&nbsp; out and different molecular parameters have been calculated. Influence&nbsp; of&nbsp; amides&nbsp; as&nbsp; AOM&nbsp; model&nbsp; has&nbsp; been investigated by using diffusion and equilibrium models. Biot number has been obtained&nbsp; in order to establish the limiting&nbsp; step&nbsp; in&nbsp; adsorption&nbsp; process.&nbsp;&nbsp; Adsorption parameters&nbsp; obtained&nbsp; in&nbsp; two-component&nbsp; adsorption systems&nbsp; were&nbsp; compared&nbsp; to&nbsp; parameters&nbsp; obtained&nbsp; for adsorption of nitrophenols alone.</p>
410

Elimination des acides humiques presents dans les eaux par adsorption et/ou photocatalyse / Removal of humic acids from water by adsorption and/or photocatalysis

Gueu, Soumahoro 26 April 2019 (has links)
Les ressources en eau sont menacées par diverses formes de pollution et les procédés de traitement proposés sont souvent complexes avec des résultats qui ne sont pas toujours satisfaisants. Cette étude vise à développer un traitement, simple et peu coûteux pour réduire au maximum la présence dans l’eau des acides humiques (AH), un polluant organique. L’approche adoptée est la mise en place d’un procédé hybride combinant l’adsorption et la photocatalyse hétérogène réalisée avec le dioxyde de titane. La méthode d’adsorption a été réalisée d’une part avec du charbon actif et d’autre part avec trois argiles provenant de la Côte d’Ivoire. Le charbon actif a été préparé à partir des coques de coco selon une procédure assez simplifiée, sans additifs chimiques, dans le souci d’obtenir un adsorbant économique et écologique. Les trois argiles brutes (Dabou, Yamoussoukro et Katiola) ont chacune subi des opérations de purification pour obtenir des fractions pures. Des tests de caractérisation réalisés par diverses techniques (analyse élémentaire, DRX, adsorption d’azote, IR, etc.) ont été effectués sur les adsorbants obtenus. Les essais d’adsorption réalisés avec le charbon ont montré qu’aucune élimination des AH n’a été observé. La raison principale serait le manque de groupements fonctionnels sur la surface du charbon préparé. Les tests d’adsorption conduit avec les argiles ont montré que ces matériaux sont capables d’éliminer les AH. Les résultats ont révélé que l’argile la plus riche en kaolinite (celle de Yamoussoukro) a une capacité d’adsorption maximale largement supérieure (115 mg/g) par rapport aux autres (20 et 15 mg/g pour Dabou et Katiola respectivement). Cette différence trouve son explication dans la composition minéralogique et structurale de chacune des argiles. Les tests de photocatalyse menés ont montré une dégradation des macromolécules d’AH en des composés de plus petites tailles. La minéralisation de la matière organique a été observée avec une réduction du carbone organique total de l’ordre de 72 et 82 % respectivement aux pH 7 et 3. En mettant en série à pH 3, les deux procédés à savoir l’adsorption suivie de la photocatalyse, une réduction de 95% du carbone organique total des AH est obtenue. Le procédé hybride ainsi réalisé montre un avantage certain car il permet d’éliminer la quasi-totalité de la pollution organique initiale. / Water resources are threatened by various forms of pollution and the proposed treatment processes are often complex with results that are not always satisfactory. This study aims to develop a simple and inexpensive treatment to minimize the presence of humic acids (HA), an organic pollutant, in water. The approach adopted is the establishment of a hybrid process combining adsorption and heterogeneous photocatalysis performed with titanium dioxide. The adsorption method was carried out primary with activated carbon and secondary with three clays from Ivory Coast. Activated carbon was prepared from coconut shell by a simplified procedure, without chemical additives, in order to obtain an economic and ecological adsorbent. The three raw clays (Dabou, Yamoussoukro and Katiola) each underwent purification operations to obtain pure fractions. Characterization tests including various techniques (elemental analysis, XRD, nitrogen adsorption, IR, etc.) were carried out on the adsorbents obtained. Adsorption tests carried out with the coal showed that no elimination of HA was observed. The main reason is the lack of functional groups on the surface of the prepared coal. The adsorption tests conducted with the clays have shown that these materials are capable of removing HA. The results revealed that the clay richest in kaolinite (Yamoussoukro) has a much higher maximum adsorption capacity (115 mg/g) compared to the others (20 and 15 mg/g for Dabou and Katiola respectively). This difference found its explanation in the mineralogical and structural composition of each of the clays. Photocatalysis tests showed a degradation of the macromolecules of HA into smaller sizes compounds. The mineralization of the organic matter was observed with total organic carbon reduction rate equal to 72 and 82% at pH 7 and 3 respectively. By placing in series the two processes namely adsorption followed by photocatalysis, the removal percentage of HA obtained at pH 3, is about 95%. This hybrid process shows an advantage since it makes it possible to eliminate almost all of the initial organic pollution.

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