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1

Shortening synthesis process of zirconium hydroxide as a hydrolysis product of sodium zirconate

Muzakky, Poernomo Herry, Prabasiwi Devi Swasti, Amiliana Rahmatika Alfia

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 3

art. no. 167965

EN

This research was focusing on shortening the process of Zirconium hydroxide (Zr(OH)4) synthesis to get a more efficient process. In the earlier method, Zr(OH)4 was produced through ZOC, which was the product of Na2ZrO3 reacted with HCl. While this study offers a new method to synthesize Zr(OH)4 through the hydrolysis process of sodium zirconate (Na2ZrO3), removing the leaching step of Na2ZrO3 with HCl. The hydrolysis process of Na2ZrO3 was carried out in a multistage stirred reactor at 70°C. The multistage hydrolysis process occurred in 13 stages with 4000 grams of feed and 890 liters of water. This process produced 2500 grams of Zr(OH)4. Then the impurities analysis was done using UV-Vis and atomic absorption spectroscopy (SAA). The UV-Vis analysis was done to analyze Si concentration, while the atomic absorption spectroscopy (SAA) was done to analyze Na concentration. Si and Na concentrations could decrease to 23.98 μg/ml and 1.05 μg/ml, respectively. The Zr(OH)4 contained in the residue was characterized using X-Ray Diffractometer (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). Then, the calcination process of Zr(OH)4 was done at 300°C and 400°C for 1 hour, and characterized using XRD. The XRD result shows crystals of zirconium titanium oxide or srilankite, and SiO2 crystals that are separated from ZrO2 or TiO2 crystals. Surface analysis was done using Scanning Electron Microscope - Energy Dispersive X-Ray (SEM-EDX), the result shows that the hydrolysis process at the 3rd, 7th, and 13th stages have different amorphous crystals with bright colors. At the 13th hydrolysis stage, Zr concentration increased to 63.38%, and Si concentration decreased. Thus, the shorter process of Zr(OH)4 synthesis has been done successfully.

2

Counterion effects on the alkali dissolution mechanism of quartz

Yao Yu-yun, Tang Yun, Yang Yong, Li Guo-hui, Wu Bo, Dai Wen-zhi

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 1

art. no. 160038

EN

In gold ore, quartz plays an important role in mineral formation by acting as the follower. Understanding counterion release, transport, and deposition in alkali solution is a prerequisite for evaluating the potential role of gold separate from quartz deposits in pretreatment. In this work, the aggregation, retention, and release of counterion in alkali solution media were investigated by kinetic research and pure mineral experiments, the correlation and mechanism of these processes were revealed by combining geochemical theory, interaction energy calculation, and quantum chemistry. The results showed that the retention and release of counterion were closely related to the dissolution and corrosion rate of quartz. The NH4+ and Fe2+ with higher mineral affinity reduced the quartz stability, and the dispersion stability and mobility of the quartz were greatly improved by an alkaline substance due to the enhancement of steric hindrance effects. Quantum chemical calculation results show that ammonium ion promotes the dissolution of quartz stronger than ferrous ion, which is mainly reflected in reducing the activation energy required for the formation of transition state (TS1), which can be verified by kinetic calculation. These findings provide essential insight into the extraction of gold coated by quartz as well as a vital reference for the experiment of gold-loaded quartz leaching in mineral processing.

3

Bioethanol Production from Chlorella Pyrenoidosa by Using Enzymatic Hydrolysis and Fermentation Method

Yerizam Muhammad, Jannah Asyeni Miftahul, Aprianti Nabila

Journal of Ecological Engineering

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2023

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Vol. 24, nr 1

34--40

EN

Starch can be found in microalgae, the raw material for the third generation of bioethanol production. One of them is C. pyrenoidosa. This study was conducted to analyze the effect of α-amylase enzyme concentration on the glucose contents produced and the effects of fermentation time on bioethanol contents produced. The hydrolysis process of this study was conducted using an α-amylase enzyme produced by A. niger. Several analyses in this research were carried out, including the analysis of enzyme activity using the Fuwa method, the analysis of glucose levels from enzymatic hydrolysis using the DNS method, and the analysis of bioethanol contents using the density method and GC-MS. The highest glucose content was 0.67 mg/mL, which was obtained from the addition of 40% (v/w) α-amylase enzyme, and the yield of bioethanol content from the sample treated 40% (v/w) α-amylase enzyme and fermented for 9 days was the optimum, which produced 28.07% of bioethanol content.

4

Anaerobic Co-Digestion of Sewage Sludge and Waste in High Solid State

Aboulfotoh Ahmed M., Marie Ahmed I., El-Hefny Rehab

Journal of Ecological Engineering

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2022

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Vol. 23, nr 6

1--13

EN

In this study, the effect of thermal pre-treatment (TP) on the physical characteristics and co-digestion of a mixture of food waste and sludge was investigated. The food waste (FW) to sewage sludge (SS) ratio used in this research is 1:2 (VS-based) to form a final concentration of 11.20%. The inoculum to substrate ratio was set at 1:1 (volumebased). Undoubtedly, the results show that TP has changed the physical characteristics of the food waste to sewage sludge mixture. The results show that the pretreatment increased the biogas production from 4385 ml for the untreated reactor to 5685 for the reactor R2(140) at 140 °C and the improvement in biogas production reaches 29.65% in the reactor R2(140) and the removal of volatile solids was 58.90%. Therefore, after the biomethane potential test, the temperature of 140 °C was found to be optimal in the production of biogas. The optimal condition is to use a mixture of pre-treated SS at the temperature of 140 °C and untreated FW, so TP is recommended to be used in anaerobic digestion of the mixture of food waste and sewage sludge.

5

Prediction of long-term performance of thermoplastic composites, based on accelerated aging test results

Siwek Artur, Malinowski Łukasz, Bednarowski Dariusz, Król Julita, Nowak Tomasz

Inżynieria Materiałowa

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2022

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Vol. 43, nr 3

32--37

EN

In this paper the results of accelerated aging tests of two grades of polybutylene terephthalate (PBT) are presented. The degradation process of the mechanical properties was monitored with the help of 3-point bending test, supported with the results of gel permeation chromatography (GPC) measurements. Based on performed experiments, it can be concluded that the hydrolysis resistant (HR) PBT ages approximately 3 times slower as compared to standard grade. To predict the long-term behaviour of studied materials, the time-temperature superposition concept was applied. The respective shift factors, describing degradation of material properties as a function of time, were derived. It was found that the temperature increases by 10°C and relative humidity (RH) increase by 10% decrease the expected material life time by a factor of 2.5 and 1.3, respectively.

PL

W artykule przedstawiono wyniki przyspieszonych testów starzenia dwóch rodzajów poli(tereftalanu butylenu) (PBT). Proces degradacji właściwości mechanicznych monitorowano za pomocą 3-punktowego testu zginania, popartego wynikami pomiarów chromatografii żelowej (GPC). Na podstawie uzyskanych wyników stwierdzono, że PBT odporny na hydrolizę (HR) starzeje się ok. 3 razy wolniej w porównaniu ze standardową wersją. Aby przewidzieć długoterminowe zachowanie badanych materiałów, zastosowano koncepcję superpozycji czasowo-temperaturowej. Wyprowadzono odpowiednie czynniki przesunięcia opisujące degradację właściwości materiału w funkcji czasu. Stwierdzono, że wzrost temperatury o 10°C i wzrost wilgotności względnej (RH) o 10% zmniejszają przewidywany czas życia materiału o odpowiednio 2,5 i 1,3.

6

Use of isoperibolic reaction calorimeter for the study of reaction kinetics of acetic anhydride hydrolysis reaction: Effect of acetic anhydride and water ratio

Kumar Rajendra, Tiwari Anurag Kumar

Chemical and Process Engineering

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2022

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Vol. 43, nr 2

255-–264

EN

Reaction kinetics of acetic anhydride hydrolysis reaction is being studied at a fixed reaction temperature and ambient pressure using an isoperibolic reaction calorimeter. Temperature versus time data along with heat and mass balance is used to determine the kinetics parameters i.e. activation energy and Arrhenius coefficient. It has been studied with the varying volumetric ratio of acetic anhydride and water; and kinetics parameters were compared and plotted for each ratio. Such a study has not been done previously to determine the kinetics dependency on varying the acetic anhydride water ratio. As the acetic anhydride hydrolysis reaction is exothermic in nature, the present study will help to decide the safe and suitable operating conditions such as concentration and temperature for conducting this reaction at plant scale. The kinetic data presented can be used further for the mathematical modeling and simulation of such exothermic hydrolysis reactions.

7

Wyznaczanie energii aktywacji oraz optymalnej temperatury reakcji hydrolizy palmitynianu p-nitrofenylu katalizowanej przez lipazy

Miłek Justyna

Przemysł Chemiczny

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2021

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T. 100, nr 1

103--104

PL

Na podstawie modelu matematycznego opisującego wpływ temperatury na aktywność lipaz z Rhizopus oryzae 3562 oraz Enterobacter aerogenes wyznaczono energie aktywacji Ea i dezaktywacji Ed oraz optymalne temperatury Topt procesu hydrolizy palmitynianu p-nitrofenylu (p-NPP). Wartości Ead, Topt wynosiły odpowiednio 32,86±14,86 kJ/mol, 59,74±8,72 kJ/mol i 298,02 ± 3,02 K dla lipazy R. oryzae 3562 oraz 45,37 ± 16,28 kJ/mol, 59,28 ± 14,07 kJ/mol i 295,00 ± 2,74 K dla lipazy E. aerogenes. Założono, że reakcje hydrolizy p-NPP katalizowane przez badane lipazy przebiegały zgodnie z kinetyką pierwszego rzędu ze względu na stężenie enzymu.

EN

Exptl. data on the temp. relationship of lipases from Rhizopus oryzae 3562 and Enterobacter aerogenes activity published by Kumari et al. (2008), were used to calc. the optimum temp., activation energies and deactivation energies of the p-nitrophenyl palmitate hydrolysis according a resp. math. model of the reaction. The calcd. values were 298.02±3.02 K, 32.86±14.86 kJ/mol and 59.74±8.72 kJ/mol for lipase from R. oryzae 3562 and 295.00 ± 2.74 K, 45.37 ± 16.28 kJ/mol and 59.28 ± 14.07 kJ/mol for lipase from E. aerogenes.

8

Alkalizacja jako metoda wstępnej hydrolizy osadu czynnego przed procesem fermentacji beztlenowej

Grübel Klaudiusz, Wacławek Stanisław

Polish Journal of Materials and Environmental Engineering

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2021

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Vol. 1 (21)

16--25

EN

The aim of the research work was to determine the possibility of initial hydrolysis of the waste activated sludge with the use of the alkalization process. On the basis of the tests performed, it was found that the obtained pH value drops quite quickly after adding NaOH. In practice, after a period of 30 minutes, a further decrease in the pH value takes place, but at a lower rate. Therefore, 30 minutes was considered as a technically valid reaction time. After this reaction time, the COD (soluble COD; S-COD) values were recorded. They represented the release of organic matter into the liquid phase. In addition, a second disintegration method was carried out, on the alkalized earlier waste activated sludge, based on the phenomenon of hydrodynamic cavitation. Carrying out such a hybrid method of destroying activated sludge flocs and microorganisms contributed to the achievement of much greater hydrolysis effects. On the basis of the conducted research, it can be concluded that the use of such hydrolysis processes lead to good results in relation to further sludge processing, e.g. anaerobic digestion, which may result in a significant improve- ment in biogas production and an increase in biogas yield.

9

Analiza jakości gazu i pomiar w kontekście technologii Power to Gas

Mularczyk Paweł

Gaz, Woda i Technika Sanitarna

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2020

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Nr 7-8

2--8

PL

Istotą technologii Power to Gas jest wytworzenie gazu (wodoru lub metanu) przy wykorzystaniu energii elektrycznej. Zazwyczaj wykorzystuje się w tym celu jej nadwyżki, pochodzące ze źródeł fotowoltaicznych lub wiatrowych. technologia Power to Gas umożliwiająca integrację systemu elektroenergetycznego z systemem gazowym przez wtłoczenie wodoru do systemu gazowniczego. Zabieg ten umożliwia to magazynowanie energii, zarówno w sieci, jak i w istniejących już magazynach. Dodatkowym atutem tego rozwiązania jest to, że rozległość sieci gazowniczych dystrybucyjnych i przesyłowych pozwala na transport energii na duże odległości. Zatłaczanie wodoru do systemu gazowniczego jest opłacalne, lecz infrastruktura systemu gazowego pozwala na wtłaczanie jedynie ograniczonej i określonej ilości wodoru.

EN

The essence of the Power to Gas technology is to produce gas (hydrogen or methane) with the use of electric energy. For this purpose, its surplus is usually used that comes for photovoltaic or wind sources. The Power to Gas technology allows to integrate a power grid system with a gas system by pumping hydrogen into a gas system. This procedure enables to store energy, both in a network and in already existing storage facilities. An additional advantage of this solution it that widespread gas distribution and transmission networks allow to transport energy on large distances. Pumping hydrogen into a gas system is cost-effective, but the infrastructure a gas system allows to pump in only a limited and specific quantity of hydrogen.

10

Metoda otrzymywania ε-kaprolaktonu przez chemo-enzymatyczne utlenianie cykloheksanonu w emulsji

Sitko Magdalena, Szelwicka Anna, Szmatoła Michał, Skwarek Andrzej, Schimmelpfennig Lech, Dziuba Krzysztof, Morawiec-Witczak Magdalena, Iłowska Jolanta, Chrobok Anna

Przemysł Chemiczny

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2019

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T. 98, nr 10

1587--1593

PL

Opracowano efektywną metodę otrzymywania ε-kaprolaktonu w wyniku chemo-enzymatycznego utleniania Baeyera i Villigera cykloheksanonu. Jako biokatalizator etapu generowania in situ nadkwasu zastosowano natywną formę lipazy B z Candida antarctica. Opracowano układ reakcyjny, w którym równoobjętościowa mieszanina prekursora nadkwasu (kwasu dekanowego) oraz cykloheksanonu pełniła funkcję rozpuszczalnika, a 35-proc. wodny roztwór nadtlenku wodoru w 2-krotnym molowym nadmiarze był utleniaczem. Uzyskano wysoką wydajność (81%) i selektywność (96%) produktu w krótkim czasie reakcji (2 h) w łagodnych warunkach (45°C, ciśnienie atmosferyczne). Proponowane rozwiązanie umożliwia prowadzenie procesu w sposób bezpieczny, z wyeliminowaniem stosowania dodatkowych rozpuszczalników. Dodatkowo, formowanie się emulsji zwiększa efektywność wymiany masy, dzięki czemu uzyskuje się korzystniejsze wskaźniki technologiczne niż w opisanych dotychczas procesach chemo-enzymatycznego utleniania cykloheksanonu do ε-kaprolaktonu.

EN

A mixt. of cyclohexanone, decanoic acid (1:1 by vol.) as well as 35% aq. H₂O₂ was applied. Cyclohexanone was used as both reagent and solvent. Native form of lipase B Candida antarctica was used as a biocatalyst to generate in situ an org. peracid. The high yield of product (81%) with very high selectivity (96%) was achieved after 2 h under mild conditions (45°C, atm. pressure).

11

Abiotyczna hydroliza wybranych antybiotyków stosowanych w weterynarii, toksyczność przewlekła produktów

Adamek Ewa, Baran Wojciech, Adamczyk Roman

Proceedings of ECOpole

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2019

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Vol. 13, No. 1-2

97--106

PL

Substancje chemiczne w hydrosferze ulegają transformacji na skutek udziału w wielu równoległych procesach chemicznych i biologicznych. Produkty takich procesów oraz ich oddziaływanie na środowisko mogą być różne. Jednym z takich procesów jest hydroliza abiotyczna. Celem badań było wyznaczenie kinetyki hydrolizy trzech wybranych, stosowanych w weterynarii antybiotyków (ampicyliny, doksycykliny i tylozyny), oraz ocena toksyczności chronicznej roztworów zawierających produkty hydrolizy tych antybiotyków. Reakcje hydrolizy prowadzono w warunkach aseptycznych w temperaturze 30 °C przez okres 144 dni przy naturalnym pH. W tym czasie oceniano zmiany stężeń badanych leków, zmiany stężeń węgla organicznego oraz zmiany sumarycznej toksyczności przewlekłej ich roztworów. W badanym przedziale czasowym wartości stałej szybkości hydrolizy dla ampicyliny, doksycykliny i tylozyny wynosiły, odpowiednio, 0,068; 0,0075 i 0,003 dni–1. W trakcie eksperymentu nie zaobserwowano obniżenia stężenia węgla organicznego w badanych próbkach, natomiast ulegała obniżeniu ich sumaryczna toksyczność przewlekła.

EN

In the hydrosphere, chemical substances are transformed by abiotic or biotic mechanisms in chemical and biological processes. The formed products and/or intermediates as well their effect on the environment may be different. One of these processes is an abiotic hydrolysis. The aim of the study was to determine the kinetics of hydrolysis of three selected antibiotics used in veterinary, i.e. ampicillin, doxycycline and tylosin. Additionally, the chronic toxicity of solutions containing the hydrolysis products of these antibiotics was assessed. Hydrolysis reactions were conducted under aseptic conditions at the natural pH (without correction) at temp. 30 °C for 144 days. At this time, the changes in drugs concentration, the changes in organic carbon content and the changes in cumulative chronic toxicity of antibiotics solutions were assessed. During the experiment, the hydrolysis rate constants for ampicillin, doxycycline and tylosin were 0.068; 0.0075 and 0.003 days–1, respectively. A decrease in the organic carbon content in the studied samples was not observed but the cumulative chronic toxicity decreased.

12

Enzymatic bioconversion of feather waste with keratinases of Bacillus cereus PCM 2849

Ciurko Dominika P., Łaba Wojciech, Piegza Michał, Juszczyk Piotr, Choińska-Pulit Anna, Sobolczyk-Bednarek Justyna

Polish Journal of Chemical Technology

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2019

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Vol. 21, nr 3

53--59

EN

Enzymatic preparation from culture of keratinolytic Bacillus cereus PCM 2849 was applied for hydrolysis of whole chicken feathers, after sulphitolytic pretreatment. This process was optimized using a three-factor Box-Behnken design, where the effect of substrate concentration, sulphite concentration during pretreatment and reaction temperature was evaluated on the release of amino acids. Obtained results revealed the highest impact of reaction temperature, followed by substrate content and sulphite during pretreatment. Optimal process conditions were established, i.e. temperature 44.4°C, feathers 4.7% and treatment with 25.3 mM sulphite. Amino acid composition of the obtained hydrolysate was analyzed. Glutamic acid (9.21 g·kg−1) and proline were dominant, however significant amount of branched-chain amino acids was also observed. The FTIR analysis of residual substrate revealed the cleavage of disulphide bonds in keratin through the presence of thioester residues. The absence of reduced cysteine residues was confirmed, along with minor changes in proportions of keratin substructures.

13

Chemical recycling of polyesters

Dębowski Maciej, Iuliano Anna, Plichta Andrzej, Kowalczyk Sebastian, Florjańczyk Zbigniew

Polimery

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2019

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T. 64, nr 11-12

764--776

EN

In the presented paper, two basic strategies that can be used in the processes of chemical recycling of polyester material were described. The first of them involves increasing the molar mass of recycled materials in the solid-state polycondensation (SSP) process and/or joining their chains with various types of substances easily reacting with the end groups of polyesters (so-called extending agents). The essence of the second strategy is the degradation of the material under the influence of various protogenic agents (such as water, alcohols, glycols and amines) to obtain low-molecular products or oligomers that can be used as raw materials in the synthesis of many classes of polymers. The methods that are already used in PET [poly(ethylene terephthalate)] recycling and the possibility of their extension to other types of polyesters are both shown.

PL

W pracy przedstawiono dwie podstawowe strategie możliwe do wykorzystania w procesach chemicznego recyklingu tworzyw poliestrowych. Pierwsza z nich polega na zwiększeniu masy molowej utylizowanych tworzyw polimerowych w procesie polikondensacji w ciele stałym (SSP) i/lub łączeniu ich łańcuchów za pomocą różnego typu substancji łatwo reagujących z grupami końcowymi poliestrów (tzw. czynników przedłużających). Istotą drugiej strategii jest degradacja tworzywa pod wpływem różnych czynników protogennych (takich jak: woda, alkohole, glikole i aminy) w celu uzyskania produktów małocząsteczkowych lub oligomerów, które można wykorzystać jako surowce w syntezie wielu klas materiałów polimerowych. Omówiono metody stosowane już w recyklingu PET [poli(tereftalanu etylenu)], a także możliwość ich rozszerzenia na inne gatunki poliestrów.

14

Utilization of Stalks Waste of Sorghum to Produce Bioethanol by Using Saccharomyces cerevisiae and S. cerevisiae-Pichia stipitis Consortium

Pandebesie Ellina S., Kartini Audiananti Meganandi, Wilujeng Susi A., Warmadewanthi IDAA

Journal of Ecological Engineering

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2019

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Vol. 20, nr 4

54--60

EN

Sweet Sorghum (Sorghum bicolor (L.) Moench) stalks as lignocellulosic agricultural biomass residues are one of the agricultural wastes that do not have economic value and are abundant enough in Indonesia. Compared to sugar cane, total sugar in the sorghum stalk had almost same juice yield. On the basis of the sufficient total sugar content in the sorghum crop residues, sorghum stalk is one of the promising potential sources for bioethanol production. This study was conducted to determine the optimum substrate concentration and microorganism capability to fermentation sorghum stalks using Separated Hydrolysis and Fermentation (SHF) method. The pretreatment conducted in this study was carried out using physical and chemical methods. The sorghum stalks were treated with chopping, drying, grinding and separate with the concentration of 25 grams (5%) and 50 grams (10%), then 0.25% H2SO4 was added and heated at the temperature of 121°C for 10 minutes. The enzymatic hydrolysis method using T.viride and A.niger was performed. After hydrolysis, 20% S.cerevisiae CC 3012 or 20% consortium S.cerevisiae CC 3012-P.stipitis were added for the fermentation process. The data obtained in this research pertanied to the value of lignin, cellulose, hemicellulose, reducing sugar, C, N, P, and bioethanol. The results of this study indicated the highest ethanol yield is produced by 50 g substrate as the optimum substrate using the consortium of S. cerevisiae CC 3012-P. stipitis for 24 hours of fermentation.

15

Membrane reactor for enzymatic depolymerization – a case study based on protein hydrolysis

Noworyta A., Trusek A., Wajsprych M.

Polish Journal of Chemical Technology

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2018

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Vol. 20, nr 4

44--48

EN

The efficiency of enzymatic depolymerization in a membrane reactor was investigated. The model analysis was performed on bovine serum albumin hydrolysis reaction led by three different enzymes, for which kinetic equations have different forms. Comparing to a classic reactor, the reaction yield turns out to be distinctly higher for all types of kinetics. The effect arises from increasing (thanks to the proper selectivity of the applied membrane) the concentration of reagents in the reaction volume. The investigations indicated the importance of membrane selectivity election, residence time and at non-competitive inhibition the substrate (biopolymer) concentration in feed stream. Presented analysis is helpful in these parameters choice for enzymatic hydrolysis of different biopolymers.

16

Coagulant cost optimization for surface water coagulation process

Wolska M., Mołczan M., Solipiwko-Pieścik A., Urbańska-Kozłowska H.

Architecture Civil Engineering Environment

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2018

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Vol. 11, no. 3

153--161

EN

This paper presents the results of a study concerning application of different coagulants used in surface water coagulation process. Even though the use of this process is quite wide-spread and several different coagulants are used it would be vital to identify which coagulants are the most effective from the economical point of view. The choice of parameter, such as doses, contact time, speed of mixing are important for cost optimization while maintaining satisfactory results for WTP. Four of the most effective coagulants were taken to the second stage. Three of the four coagulants chosen for the second stage of the study were the same for both tests regardless at water quality parameters. The cost of the process depended above all on raw water contamination, and therefore the coagulant dosage. An analysis of the results has shown that only the non pre-hydrolyzed coagulant allowed for high process effectiveness at low process costs. This coagulant was also the only one to require a pH correction after coagulation. However, this did not significantly increase the coagulation cost.

17

Wydajność procesów hydrolizy i fermentacji w technologii wytwarzania bioetanolu z drewna topoli (Populus sp.)

Szadkowski J., Radomski A., Antczak A., Szadkowska D., Lewandowska A., Marchwicka M., Kupczyk A.

Przemysł Chemiczny

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2017

|

T. 96, nr 3

518--520

PL

Drewno topoli (Populus sp.) rozdrobnione do postaci wiórów (frakcja 0,43-1,0 mm) poddano ekstrakcji mieszaniną chloroform-etanol. Tak przygotowane wióry posłużyły do uzyskania celulozy metodą Kürschnera i Hoffera i holocelulozy metodą z użyciem chloranu(III) sodu. Następnie celulozę i holocelulozę poddano hydrolizie enzymatycznej za pomocą handlowych enzymów Dyadic Cellulase CP CONC (pH 5,3) i Dyadic Xylanase 2XP CONC (pH 5,4). Hydrolizowano także drewno nieekstrahowane. Proces hydrolizy enzymatycznej prowadzono przez 24 h i 60 h. Hydrolizaty po 60 h poddano dodatkowo fermentacji alkoholowej przy zastosowaniu drożdży gorzelniczych (Saccharo-myces cerevisiae). Uzyskany alkohol poddano destylacji prostej i analizie HPLC.

EN

Poplar wood (Populus sp.) was ground to chips (0.43-1.0 mm) and extd. with a CHCl3/EtOH mixt. to obtain Kürschner-Hoffer cellulose and chlorite holocellulose. All the materials were hydrolyzed with Dyadic Cellulase CP CONC (pH 5.3) and Dyadic Xylanase 2XP CONC (pH 5.4) for 24 and 60 h. Non extd. wood was also hydrolyzed for comparison. The hydrolyzates after 60 h were fermented to EtOH with a distillery yeast (Saccharomyces cerevisiae). The resulted alc. was septd. by simple distn. and analyzed by high-performance liq. chromatog.

18

Enzymatic activity of some industrially-applied cellulolytic enzyme preparations

Dąbkowska K., Mech M., Kopeć K., Pilarek M.

Ecological Chemistry and Engineering. S

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2017

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Vol. 24, nr 1

9--18

EN

Enzymatic hydrolysis is the essential step in the production of 2nd generation biofuels made from lignocellulosic biomass, i.e. agricultural or forestry solid wastes. The enzyme-catalysed robust degradation of cellulose and hemicellulose to monosaccharides requires the synergistic action of the independent types of highly-specific enzymes, usually offered as ready-to-use preparations. The basic aim of the study was to experimentally determine the enzymatic activity of two widely industrially-applied, commercially available cellulolytic enzyme preparations: (i) Cellic® CTec2 and (ii) the mixture of Celluclast® 1.5L and Novozyme 188, in the hydrolysis of pre-treated lignocellulosic biomass, i.e. (a) energetic willow and (b) rye straw, or untreated (c) cellulose paper as well, used as feedstocks. Before the hydrolysis, every kind of utilized lignocellulosic biomass was subjected to alkaline-based (10% NaOH) pre-treatment at high-temperature (121°C) and overpressure (0.1 MPa) conditions. The influence of the type of applied enzymes, as well as their concentration, on the effectiveness of hydrolysis was quantitatively evaluated, and finally the enzyme activities were determined for each of tested cellulolytic enzyme preparations.

19

Podatność polilaktydu na degradację w wybranych składnikach kosmetyków

Krasowska K.

Zeszyty Naukowe Akademii Morskiej w Gdyni

|

2016

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nr 93

146--151

PL

Celem pracy była ocena podatności polilaktydu (PLA) na degradację w wybranych składnikach kosmetyków oraz określenie wpływu modyfikacji PLA na szybkość jego degradacji. Degradację prowadzono w temperaturze 40oC w: wodzie, etanolu, etanolowym roztworze kwasu salicylowego i ciekłej parafinie. Podatność na degradację oceniano na podstawie obserwacji makro- i mikroskopowych powierzchni, zmian masy, twardości i krystaliczności PLA przed degradacją i po niej w wybranych mediach. Stwierdzono, że PLA jest podatny na degradację w niektórych mediach, będących składnikami kosmetyków, a szybkość procesu jego rozpadu zależy od rodzaju medium degradacji i od zastosowanej modyfikacji PLA. Uzyskane wyniki mogą stanowić wskazówkę dla projektantów opakowań dotyczącą możliwości wykorzystania PLA w przemyśle opakowaniowym produktów kosmetycznych.

EN

The estimation of degradability of poly(lactide) (PLA) in the selected cosmetic ingredients and determination of the influence of modification of PLA on the rate of degradation process was the subject of this paper. Degradation was carried out in distilled water, ethanol, salicylic acid in ethyl solution and liquid paraffin at the temperature 40°C. The degradability of PLA was studied by macro- and microscopic observations of surfaces, changes of weight, hardness and crystallinity of polymer samples before and after incubation. The obtained results indicate that PLA was susceptible to degradation in selected cosmetic ingredients. The rate of degradation process depends on the type of medium and used modification of PLA. These results can provide indications for designers of packaging concerning the possibility of the use of PLA in the packaging industry of cosmetic products.

20

Application of fibres from recycled PET bottles for concrete reinforcement

Wiliński D., Łukowski P., Rokicki G.

Journal of Building Chemistry

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2016

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Vol. 1, iss. 1

1-9

EN

Waste PET can be reused as partial or complete substitute of an aggregate in a concrete composition or as a concrete reinforcement. However, the main drawback of such applications is the hydrolysis of ester linkages of poly(ethylene terephthalate) in highly alkaline environment of the cement matrix. To prevent alkaline hydrolysis, the PET fibres were coated with commercially available ethylene/vinyl acetate copolymer (EVA). Effectiveness of the use of copolymer EVA as a protection layer against strong alkali solutions has been demonstrated and discussed. Chemical changes in PET fibres after alkaline treatment have been referred to mechanical properties of the fibres. Mechanical properties, like compressive and flexural strength of the composites as well as the long-term durability performance of recycled PET fibres in alkaline environment were also investigated. The preliminary results indicated that the introduction of the PET fibres does not deteriorate the mechanical strength of the concrete composite.