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Some coal mines suffer from problem of having huge deposits of bentonite that they regard as undesirable, since bentonite can cause problem due to its swelling property. Instead of piling stacks of bentonite and regarding it as ecological problem the bentonite can be used as enzyme support by immobilization of enzymes as the challenging new application in the field of biotechnology. The enzyme catalysts in the industrial application present lower energy costs and are more environmentally friendly in comparison to traditional chemical processes. The advantages of enzymes are even more prominent when enzymes are applied in immobilized form. In this work the enzyme supports were prepared from bentonite from Coal mine "Bogovina", Serbia where bentonite, although valuable resource, is still considered to be tailings. Bentonite was modified by common methods: acid activation (AA), pillaring (P), and pillaring followed by acid activation (PAA) and tested as enzyme support. All the obtained materials were characterized by the X-ray powder diffraction and FTIR spectroscopy. The amylase, xylanase, and pullulanase were immobilized on different bentonite based supports by 24 h adsorption at 25 °C. The experimental results revealed that under the investigated conditions AA, P, and PAA, were the most suitable for amylase (106 IU/g), xylanase (74 IU/g), and pullulanase (45 IU/g) immobilization, respectively.

Catalytic degradation of Tartrazine in the presence of Oxone® activated by Co-supported chitosan derived carbon-montmorillonite as catalyst was investigated. The catalyst was synthetized using impregnation-carbonization method. The carbonization temperature was 500 °C. The catalytic experiments were performed at different temperatures in range from 25 °C to 40 °C in order to determinate kinetics parameters. The kinetics data showed best fit with the first-order kinetics model. The activation energy of the investigated degradation process was calculated according to the Arrhenius equation.

Our previous study demonstrated that cobalt content strongly affected the electro-activity of aluminum pillared clay-supported cobalt (CoAP) toward glucose oxidation. It was found that the electro-activity of CoAP increased with the increase of cobalt loading. However, at the 10 wt.% of cobalt content, the electro-activity significantly decreased. In the present study, the focus is on the investigation of the nature of the surface sites that might cause the difference in the electro-activity of CoAP. For this purpose, CoAP with 3 wt.% and 10 wt.% cobalt contents (x%CoAP, x=3 and 10) were characterized using FE-SEM and HR-TEM with EDX techniques, and XPS. The microscopic techniques coupled with EDX have shown that cobalt oxide nanoparticles were evenly distributed in both samples. However, the higher cobalt loading resulted in cobalt oxide agglomeration that led to larger particle sizes. The results of XPS confirmed the presence of Co (II) in the 3%CoAP. On the other hand, the presence of Co3O4 which contains both Co (II) and Co (III) was confirmed in 10%CoAP. It is clear from this study that the electro-activity of CoAP strongly depends on the oxidation state of cobalt. However, the effect of agglomeration and cobalt oxide particle sizes cannot be ruled out.

Mixed Al, Fe pillared clay (AlFePILC) was synthesized from Na-exchanged Wyoming clay (Na-Wy) rich in montmorillonite. In the pillaring process Na-Wy was modified with a mixed intercalating (Al, Fe) solution with molar ratio of Fe3+/(Al3++Fe3+) = 10%. The obtained AlFePILC was impregnated with cobalt using the incipient wetness impregnation method, dried at 110 ºC and calcined at 450 ºC (Co-AlFePILC). Co-AlFePILC was tested as a catalyst in catalytic oxidation of tartrazine in the presence of Oxone®. Decolorization was monitored at wavelength =426 nm, while degradation of aryl groups was followed at =257 nm using UV-Vis spectroscopy. The influence of the mass of the catalyst on degradation process was followed in the mass range from 10 mg to 50 mg at 30 °C. It was found that mass increase was beneficial for the decolorization rate. The effect of temperature was investigated from 30 ºC to 60 ºC. The decolorization was over 90% after only 10 minutes for the temperature of 60 ºC, while with the temperature decrease, the decolorization rate decreased. Co-AlFePILC was found to be an efficient catalyst in degradation of tartrazine in the presence of Oxone®.

In this work smectite pillared with mixture of aluminium and cobalt poly(hydroxo metal) cations (Al,Co-PILC) was synthesized and tested as catalyst in degradation of food dye tartrazine by peroxymonosulfate. The Al,Co-PILC was obtained using a common procedure consisting of the following steps: grinding, sieving, Na exchange, intercalation, drying and calcination. Co2+ to (Al3++Co2+) molar ratios in the pillaring solution was 10%. Catalytic tests were carried out in a semibatch reactor under stirring and constant temperature maintained by circulation of thermostatic fluid using Julabo MC 4 heating circulator. Initial dye concentration was 50 ppm in the presence of excess of peroxymonosulfate. Decolorization of tartrazine solution was monitored using UV-Vis spectrophotometry at max= 426 nm. The influence of the mass of the catalyst and reaction temperature was investigated. Catalyst mass and temperature increase were beneficial for dye degradation rate. The catalytic process at 30 ºC reached 97% for 120 min and besides decolorization included further degradation of products of tartrazine oxidation. At 50 ºC complete decolorization occurred for only 30 min. This work showed that application of smectite pillared with mixture of aluminium and cobalt poly(hydroxo metal) cations as peroxymonosulfate activators for degradation of water pollutants is very promising.

α-Amylase from Bacillus paralicheniformis (BliAmy) is a highly efficient raw starch digesting enzyme. Starch is an inexpensive source of many food industrial products. Naturally occurring clay are non-toxic, environmentally friendly and inexpensive. Therefore, immobilization of BliAmy by adsorption on three differently modified bentonites was studied. Modifications included common Na-exchange procedure, acid activation, and alkali activation. The modified clays were characterized by X-ray powder diffraction, mercury intrusion porosimetry and the points of zero charge were determined. The adsorption of the enzyme was significantly influenced by the type of modification of bentonite, being the highest for the acid-activated bentonite with the highest porosity. On the other hand, the highest enzyme activity for immobilized α-amylase was obtained with alkali-modified bentonite (98 U/g), suggesting it as a good candidate for immobilization of α-amylase for application in the food industry.

Catalytic advanced oxidative degradation of organic pollutants in water is a promising technique for the purification of industrial effluents. Cobalt-based catalysts wa proven to be very efficient in peroxymonosulfate activation and generation of SO4•− radicals, species with high oxidative potential [1]. This work, for the first time, reports the hydrothermal procedure in the synthesis of cobalt-containing chitosan-derived carbon-smectite catalyst. The obtained catalyst was used for activation of Oxone® (potassium peroxymonosulfate). Activated Oxone® was applied in catalytic degradation of toxic textile dye - Orange G dye, that was used as a model of the water pollutant. Based on the presented results, the catalyst can be considered as an eco-friendly catalyst that was evaluated as highly efficient in the process of the oxidative degradation of selected organic dye, and potentially for a variety of water pollutants.

In this work cobalt-supported carbon-smectite catalyst was synthesized and tested as peroxymonosulfate (in form of Oxone®) activator in the degradation of food dye tartrazine. The incipient wetness impregnation method was used to introduce cobalt species into chitosan-smectite biocomposite. The impregnated sample was carbonized in a tube furnace at 500 ºC in a nitrogen atmosphere. The obtained catalyst was characterized by FTIR spectroscopy and N2 physisorption. The FTIR spectra indicated the presence of bands characteristic for carbonaceous structures. It was observed that the presence of cobalt has a significant impact on the textural properties of the resulting cobalt-supported carbon-smectite catalyst. Catalytic tests were performed in 50.0 mg dm-3 tartrazine solution using 10 mg of catalyst in the presence of 0.130 mmol Oxone®. As the first step in catalytic degradation of tartrazine solution, decolorization was monitored using UV-Vis spectrophotometry at λmax= 426 nm. The catalytic process was fast at 30 ºC and besides decolorization included further degradation of products of tartrazine oxidation. After 60 minutes of reaction, the degree of decolorization reached 97%. The influence of the initial pH of reaction solution on catalytic efficiency was tested.

The aluminum pillared clay (AP) was synthesized and impregnated with various cobalt loadings (x%CoAP, x=1, 3, 5, and 10 wt.%) by incipient wetness impregnation method. All samples were characterized by using X-ray powder diffraction (XRPD), inductively coupled plasma optical emission spectroscopy (ICP-OES) and low temperature N2 physisorption techniques. The chemical analysis confirmed the successful incorporation of cobalt in all impregnated samples. Nevertheless, only cobalt oxide (Co3O4) was identified for samples having higher cobalt contents. Furthermore, different cobalt loading was mainly affected the microporous region in such way that micropore surface area decreased with the increase of cobalt.

Chemical degradation by activated Oxone® is one of the most attractive advanced oxidation processes (AOPs) for the treatment of various pollutants including toxic azo dyes. However, the development of an effective heterogeneous catalyst for activating Oxone® is still challenging. In this work a novel cobalt supported carbon-smectite catalyst (Co/cC-S) was prepared through a two-step synthesis. First, the incipient wetness impregnation method was used for the cobalt species to be introduced into chitosan-smectite biocomposite. The impregnated sample was then carbonized in a tube furnace at 400 °C in a nitrogen atmosphere for 1h. The obtained catalyst was characterized using FTIR spectroscopy and low temperature N2 physisorption. The Co/cC-S catalyst was tested as peroxymonosulfate (in the form of Oxone®) activator in the degradation of two textile dyes, Acid orange 10 (AO10) and Basic Blue 41 (BB41), from their single component and two component aqueous solution. As the first step in catalytic degradation of dyes, decolorization was monitored using UV-Vis spectrophotometry (λmax=478 nm and 605 nm, for AO10 and BB41, respectively). The results showed that Oxone® alone is ineffective in the degradation of both dyes. The combination of Co/cC-S and Oxone® significantly improved their degradation. The investigated catalytic process at 30 °C in the single component dye solution was very fast for AO10 and somewhat slower for BB41. The AO10 decolorization from the two-component solution was as fast as from the single component solution. On the other hand, the degradation efficiency for BB41 substantially decreased when two dyes co-existed. This result suggests that Co/cC-S activated Oxone® exhibited a relatively high priority for attacking AO10. Co/cC-S showed to be a promising peroxymonosulfate activator in the catalytic treatment of wastewaters containing textile azo dyes.

CASE REPORT — patient M.T., female, age 21, diagnosis paranoid schizophrenia (F20.O) with severe form of extrapyramidal syndrome (EPS). Patient was hospitalized in University Department of Psychiatry in the year 2007 within 3-month period. In the beginning of the treatment patient is mutistic, in the state of stupor with muscular rigidity, reacting on the rough stimulus, with hyperthermia, hypotension and incontinence of urine and stool. Parenteral appliance of nutrition and therapy is maintained. After a week there is a improvement regarding peroral intake of therapy and little amounts of mash food, with the help and encouragement of the medical staff. During short time periods patient is sitting in the wheel chair or takes a few steps (by the aid) inside of the room, with the presence of rigidity of the body and tether walk. After three weeks patient is more independent, with deficient contact, regulation of urine and stool is established during the day. After two months of hospitalization in the acute department she is transferred in the department of sociotherapy without the presence of psychopathological symptoms and neurological side effects which were expressed during first month of treatment. Aim: to point out the importance of performing the adequate health care