• Publicationsclose
• Research dataclose
• Research softwareclose
• Open Access close
• Kemija u Industriji close

Blast furnace sludge-BFS is a by-product and waste material of the iron and steel industry. Recently, the adsorption capabilities of blast furnace sludge have been attracting great interest. It is known that materials with modified surface properties can be obtained by different chemical and thermal treatments. The aim of this work was to investigate the influence of chemical treatment by acetic acid and thermal treatment by heating at 700 °C, on the surface properties of blast furnace sludge. Chemical treatment was performed by acetic acid adsorption on BFS. Microscopic observation was conducted using scanning electron microscopy (SEM method). Changes in examined surface area properties were analyzed by Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH) methods. Increasing of specific surface area, decreasing of pore size and better pore size distribution in BFS samples were registered after the applied experimental procedure. The obtained results revealed that the performed chemical and heat treatment presented the activation of blast furnace sludge. Različitim postupcima kemijske i toplinske obrade mogu se dobiti materijali poboljšanih površinskih svojstava. Visokopećni mulj - VPM je nusproizvod i otpadni materijal industrije željeza i čelika, čije su adsorpcijske sposobnosti u posljednje vrijeme sve zanimljivije. Cilj ovog rada je ispitivanje utjecaja kemijske i toplinske obrade na površinska svojstva VPM. Kemijska obrada je provedena octenom kiselinom, a toplinska zagrijavanjem visokopećnog mulja na 700 °C. Mikroskopska ispitivanja provedena su pretražnom elektronskom mikroskopijom (SEM). Promjene ispitanih površinskih svojstava analizirane su metodama Brunauer-Emmett-Teller (BET) i Barrett-Joyner-Halenda (BJH). Povećanje specifične površine, smanjenje veličine pora i bolja raspodjela pora VPM-a registrirani su nakon provedenih ispitivanja. Dobiveni rezultati pokazali su da provedena kemijska i toplinska obrada predstavljaju aktivaciju visokopećnog mulja.

Today's chemical and physical-chemical wastewater discoloration methods do not completely meet demands regarding degree of discoloration. In this paper discoloration was performed using Fenton (FeSO4 · 7 H2O + H2O2 + H2SO4) and Fenton-like (FeCl3 · 6 H2O + H2O2 + HCOOH) chemical methods and physical-chemical method of coagulation/flocculation (using poly-electrolyte (POEL) combining anion active coagulant (modified poly-acrylamides) and cationic flocculant (product of nitrogen compounds) in combination with adsorption on activated carbon. Suitability of aforementioned methods was investigated on reactive and acid dyes, regarding their most common use in the textile industry. Also, investigations on dyes of different chromogen (anthraquinone, phthalocyanine, azo and xanthene) were carried out in order to determine the importance of molecular spatial structure. Oxidative effect of Fenton and Fenton-like reagents resulted in decomposition of colored chromogen and high degree of discoloration. However, the problem is the inability of adding POEL in stechiometrical ratio (also present in physical-chemical methods), when the phenomenon of overdosing coagulants occurs in order to obtain a higher degree of discoloration, creating a potential danger of burdening water with POEL. Input and output water quality was controlled through spectrophotometric measurements and standard biological parameters. In addition, part of the investigations concerned industrial wastewaters obtained from dyeing cotton materials using reactive dye (C. I. Reactive Blue 19), a process that demands the use of vast amounts of electrolytes. Also, investigations of industrial wastewaters was labeled as a crucial step carried out in order to avoid serious misassumptions and false conclusions, which may arise if dyeing processes are only simulated in the laboratory. Današnje kemijske i fizikalno-kemijske metode obezbojavanja otpadnih voda ne zadovoljavaju u potpunosti zahtjeve vezane uz stupanj obezbojavanja. U ovom radu obezbojavanje se provodilo pomoću Fentonove kemijske metode (FeSO4· 7 H2O + H2O2 + H2SO4) i modificirane Fentonove kemijske metode (FeCl3 · 6 H2O+H2O2+ HCOOH), te pomoću fizikalno-kemijske metode upotrebom koagulanata/flokulanata (polielektrolita-POEL), koja kombinira anionski koagulant (modificirani poliakrilamid) i kationski flokulant (produkt dušikovih spojeva) uz adsorpciju na aktivnom ugljenu. Prihvatljivost opisanih metoda ispitivana je za reaktivna i kisela bojila, s obzirom na njihovu raširenu primjenu u tekstilnoj industriji. Također, provedena su ispitivanja na bojilima različitih kromogena (antrakinon, ftalocijanin, azo i ksanten) s ciljem određivanja važnosti prostorne strukture molekule. Oksidativno djelovanje Fentonovog i modificiranog Fentonovog postupka dovodi do razgradnje obojenog kromogena i visokog stupnja obezbojavanja. Međutim, ustanovljena je nemogućnost dodavanja POEL u stehiometrijskom odnosu (također prisutno kod modificiranog Fentonovog postupka), odnosno dodavanje koagulanata u suvišku kako bi se postigao viši stupanj obezbojavanja, što u konačnici dovodi do opterećenja voda POEL-ima. Kvaliteta vode na ulazu i izlazu kontrolirana je pomoću spektrofotometrijskih mjerenja i uobičajenih bioloških parametara. U prilog tome, dio ispitivanja bio je vezan za industrijske otpadne vode bojadisaone, u kojoj se pamučni materijal bojadisao bojilom C. I. Reactive Blue 19 i to tehnološkim postupkom koji zahtijeva uporabu velike količine elektrolita. Također, ispitivanje industrijskih otpadnih voda označeno je ključnim korakom izbjegavanja niza krivih pretpostavki i zaključaka, koji bi mogli nastati u slučaju laboratorijskog simuliranja procesa bojadisanja.

The seeds of the castor oil plant (Ricinus communis L.) are commonly used for obtaining castor oil that has various use in several industries, such as chemical, pharmaceutical, agricultural, and other industrial sectors. It is utilised for the production of care products, such as soaps and shampoo, lubricants, plastics, etc. Previous research has shown the benefits of using castor oil as a biodiesel and a renewable energy source. The aim of this work was to determine the physical and chemical properties of castor oil. Physical and chemical properties of selected sample of castor oil were analysed according to standard analytical methods for fats and oils. The results of analysis showed that castor oil, due to its physical and chemical properties, has a potential and relevance in cosmetic and pharmaceutical application. It can be used as raw material in different formulations, as well as for production of valuable co-products, such as glycerol. Sjemenke biljke ricinusa (Ricinus communis L.) obično se upotrebljavaju za dobivanje ricinusova ulja, koje ima različitu primjenu u nekoliko industrija, kao što su kemijska, farmaceutska, poljoprivredna i druge industrijske grane. Upotrebljava se za proizvodnju sredstava za njegu, kao što su sapuni i šamponi, lubrikanti, plastika itd. Prethodna istraživanja pokazala su prednosti uporabe ricinusova ulja kao biodizela i obnovljivog izvora energije. Cilj ovog rada bio je odrediti fizička i kemijska svojstva ricinusova ulja. Fizička i kemijska svojstva odabranog uzorka ricinusova ulja analizirana su prema standardnim analitičkim metodama za masti i ulja. Rezultati analize pokazali su da ricinusovo ulje zbog svojih fizičkih i kemijskih svojstava ima potencijal i značaj u kozmetičkoj i farmaceutskoj primjeni. Može se upotrebljavati kao sirovina u različitim formulacijama, kao i za proizvodnju vrijednih nusproizvoda, poput glicerola.