Mia Gotovuša, Ivona Pečurlić, Valentino Petrić, Paula Huzjak, Marta Krasić, Martina Zadravec, Lucija Konjević, Fabio Faraguna
{"title":"Influence of Reaction Parameters and Feedstock Type on the Synthesis of Fatty Acid Propyl, Butyl, Isobutyl, Pentyl, and Isopentyl Esters","authors":"Mia Gotovuša, Ivona Pečurlić, Valentino Petrić, Paula Huzjak, Marta Krasić, Martina Zadravec, Lucija Konjević, Fabio Faraguna","doi":"10.15255/cabeq.2023.2184","DOIUrl":"https://doi.org/10.15255/cabeq.2023.2184","url":null,"abstract":"In recent decades, conventional biodiesel synthesis from methanol or ethanol and sunflower and rapeseed oil as feedstock has also introduced the use of higher and branched alcohols and the use of waste sources of triglycerides. This study examined the influence of reactant molar ratio (5:1–12:1), mass fraction of the potassium hydroxide catalyst (1–3 wt%), time (30–120 min), type of feedstock and alcohol on the conversion of fatty acid alkyl esters. The results showed that the presence of structural branching had a negative influence on the reaction conversion. Regarding the feedstocks, the high - est conversions were obtained when using coconut oil rich in short-chain saturated fatty acids, while the conversions of biodiesel obtained from animal fat and unsaturated oils were lower. Molar ratio of the reactants and the mass fraction of the catalyst had the highest influence on the reaction conversion.","PeriodicalId":9765,"journal":{"name":"Chemical and Biochemical Engineering Quarterly","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135591029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Lauric Acid-based Polyol Esters as Potential Bio-based Lubricants for Diesel Fuel","authors":"Ivan Pucko, Kristina Crnjac, Fabio Faraguna","doi":"10.15255/cabeq.2023.2185","DOIUrl":"https://doi.org/10.15255/cabeq.2023.2185","url":null,"abstract":"In this paper, lubricants based on lauric acid and different polyols – neopentyl glycol (NPG), trimethylolpropane (TMP) and pentaerythritol (PE) – were synthesized. After purification, their purity of > 97 mol% was confirmed by infrared spectroscopy and pro - ton nuclear magnetic resonance. Synthesized lubricants 100 to 5000 ppm formulations with diesel showed similar density, kinematic viscosity, and low-temperature behavior to diesel according to standard tests, meaning that they can be used in current diesel engines. They have improved the lubricity of the formulations, as confirmed by a lower coefficient of friction, and an almost 50 % improvement in wear scar diameter (accord - ing to EN 12156-1).","PeriodicalId":9765,"journal":{"name":"Chemical and Biochemical Engineering Quarterly","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135592391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Martina Miloloža, Ula Rozman, D. Kučić Grgić, Gabriela Kalčikova
{"title":"Aquatic Toxicity of Polyethylene and Microcrystalline Cellulose Microbeads Used as Abrasives in Cosmetics","authors":"Martina Miloloža, Ula Rozman, D. Kučić Grgić, Gabriela Kalčikova","doi":"10.15255/cabeq.2023.2181","DOIUrl":"https://doi.org/10.15255/cabeq.2023.2181","url":null,"abstract":"Microplastics have been part of personal care products for years, but due to micro - plastic pollution, many companies have replaced microplastics with natural particles, such as microcrystalline cellulose. Although natural particles are considered more envi - ronmentally friendly, their ecotoxicological profile is unknown. In this context, the aim of this study was to compare the ecotoxicity of polyethylene and microcrystalline cellu - lose microbeads, both extracted from a cosmetic product. The effects of the two types of particles on the aquatic macrophyte Lemna minor and the crustacean Daphnia magna , as well as the bioadhesion of the particles to Lemna minor were evaluated. The results showed no significant effects of either particle on the specific growth rate, root length, and chlorophyll content of Lemna minor . The bioadhesion of both types of particles to the plant biomass was comparable. Furthermore, no significant effects were observed on the mobility and body length of Daphnia magna . Thus, the investigated polyethylene and cellulose microbeads showed no significant toxic effects on the tested organisms. How - ever, due to the persistence of polyethylene in the environment, the use of polyethylene microbeads in cosmetics and personal care products should be avoided","PeriodicalId":9765,"journal":{"name":"Chemical and Biochemical Engineering Quarterly","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135592222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Liverić, Tamara Holjevac Grgurić, E. Govorčin Bajsić, Marko Kršulja
{"title":"Effect of Silver Addition on Cu-based Shape Memory Alloys","authors":"L. Liverić, Tamara Holjevac Grgurić, E. Govorčin Bajsić, Marko Kršulja","doi":"10.15255/cabeq.2023.2186","DOIUrl":"https://doi.org/10.15255/cabeq.2023.2186","url":null,"abstract":"Shape memory alloys (SMAs) are smart materials with unique properties of super-elasticity and shape memory effect. These properties are the consequence of thermoelastic martensitic transformation, which can occur under thermal or mechanical deformation. Cu-Al-Ag alloys have high temperatures of martensite transformation, unlike other SMAs, which makes them suitable for use in specific applications. In this paper, Cu-10Al-1Ag alloy was prepared by melting pure metals in an electric arc furnace and casting the melt in a cylindrical mold. The microstructure of the as-cast and quenched material was determined by optical microscopy (OM) and scanning electron microscopy (SEM) equipped with energy dispersive analysis (EDS). X-ray diffraction (XRD) analysis was performed to identify crystal phases in the microstructure, while transformation temperatures were determined by differential scanning calorimetry (DSC). The hardness of Cu-Al-Ag SMA was also determined with a microhardness tester. The results showed partially formed martensite in the as-cast state, and fully formed martensite structure, 18R-type, in the quenched Cu-10Al-1Ag alloy.","PeriodicalId":9765,"journal":{"name":"Chemical and Biochemical Engineering Quarterly","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135592214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Filip Brleković, Katarina Mužina, Sanislav Kurajica
{"title":"Characterization of Sol-gel Derived Cobalt-doped Willemite via 2D Correlation Spectroscopy","authors":"Filip Brleković, Katarina Mužina, Sanislav Kurajica","doi":"10.15255/cabeq.2023.2189","DOIUrl":"https://doi.org/10.15255/cabeq.2023.2189","url":null,"abstract":"Cobalt blue is one of the world’s most famous blue pigments, but it presents a threat to human health since it is toxic when inhaled or ingested. A safer and environmentally preferable way of obtaining cobalt blue-like pigments is doping of various nontoxic compounds with small amounts of cobalt. In this work, doping of zinc silicate (willemite, Zn 2 SiO 4 ) was carried out with 5, 10, and 15 mol% of Co with the aim of obtaining Zn 2– x Co x SiO 4 solid solution. Thermal properties of sol-gel derived samples were examined with simultaneous differential thermal and thermogravimetric analysis (DTA/TGA), which showed dehydration, decomposition, and burning effects, accompanied with mass loss and willemite crystallization effect at 800 °C. X-ray powder diffraction analysis (XRD) indicated the formation of willemite phase at 800 °C, accompanied with ZnO phase and increase in willemite crystallinity with annealing temperature rise from 800 to 1100 °C. Fourier transform infrared spectroscopy (FTIR) showed characteristic bands for present oxides and their bonds along with adsorbed water and carbon dioxide. Coloura-tion of prepared samples changed with annealing temperature, whereas higher Co concentrations and temperatures accentuated the intense blue colour. Diffuse reflectance spectroscopy (DRS) revealed an increase in absorbance with annealing temperature and specific bands as a result of different Co coordination present in the samples. The 2D correlation analysis of FTIR and UV-Vis spectra of the samples thermally treated at various temperatures was utilized to investigate and correlate the changes in the structure with the rise of the annealing temperature. The obtained correlation facilitated the finding of optimal process parameters for the desired pigment quality","PeriodicalId":9765,"journal":{"name":"Chemical and Biochemical Engineering Quarterly","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135592714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Converting Waste into Products and Energy Using Complete Circular Economy and the Hydrogen Effect Technique to Reduce Dependence on Natural Gas","authors":"A. Kovač Kralj","doi":"10.15255/cabeq.2022.2157","DOIUrl":"https://doi.org/10.15255/cabeq.2022.2157","url":null,"abstract":"Conversion of waste into products and energy has the potential to reduce CO 2 emis - sion through implementation of a complete circular economy and utilisation of the hy - drogen effect technique. This study considers the novelties of the hydrogen effect tech - nique, which incorporates an upgraded input unit mathematical model. It includes real-simulated results obtained using an Aspen Plus ® simulator, and enlarged production. This technique is developed for optimal municipal solid waste (MSW) combustion, gas - ification, and reforming, presented as an upgraded input unit for syngas production, which can reduce CO 2 emissions by 3·10 6 kmol a –1 . This approach is exemplified by utilizing existing methanol and dimethyl ether production processes from natural gas, as they can be achieved and exceeded using MSW with varying hydrogen amounts. The optimal upgraded methanol and dimethyl ether production processes can increase pro - duction by 47 % and 16 %, including only the upgraded input unit, as well as decrease the temperature in the product reactors by 30 °C.","PeriodicalId":9765,"journal":{"name":"Chemical and Biochemical Engineering Quarterly","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46952828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of Process Parameters on Chitosan-mediated Microalgae Flocculation","authors":"S. Akiş, B. Inan, D. Özçimen","doi":"10.15255/cabeq.2022.2152","DOIUrl":"https://doi.org/10.15255/cabeq.2022.2152","url":null,"abstract":"Today, microalgae have received considerable interest as an alternative feedstock for biofuel, animal feed, human food, and pharmaceuticals because they possess valuable oils and biomolecules. The main problem of the cost of microalgae production is generally associated with the harvesting process. Flocculation is an effective method to harvest microalgal biomass and minimize the operating cost. In this study, the effect of the chitosan solution, different pH conditions, and flocculation time on flocculation process of Chlorella minutissima and Nannochloropsis oculata were investigated, and the obtained data were evaluated statistically. Flocculation efficiency of C. minutissima and N. ocula ta were the highest under the conditions of 10 pH, 100 mg L –1 chitosan concentration, and flocculation time of 60 min, and found as 97 % and 85 %. It was also found that chitosan flocculation could be improved with pH increase. This study showed that chitosan is a favorable flocculant because of its high efficiency, being non-toxic, and en-abling the reusability of the growth medium after flocculation.","PeriodicalId":9765,"journal":{"name":"Chemical and Biochemical Engineering Quarterly","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45166028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Bashyal, S. Aryal, R. Rai, P. Lohani, S. K. Gautam, M. R. Pokhrel, B. R. Poudel
{"title":"Effective Biosorption of Phosphate from Water Using Fe(III)-Loaded Pomegranate Peel","authors":"N. Bashyal, S. Aryal, R. Rai, P. Lohani, S. K. Gautam, M. R. Pokhrel, B. R. Poudel","doi":"10.15255/cabeq.2022.2174","DOIUrl":"https://doi.org/10.15255/cabeq.2022.2174","url":null,"abstract":"Removal of phosphate from wastewater is necessary for the safety of public health and environmental protection. The present study used an easily available and affordable biosorbent obtained from the pomegranate peel for the excision of phosphate from water. The biosorption behavior of raw pomegranate peel powder (RPGPP) was found negligible. The RPGPP was further saponified with Ca(OH) 2 followed by Fe(III) loading to obtain Fe(III)-loaded pomegranate peels (Fe(III)-PGPP), which was then employed for the phosphate uptake. Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray (EDX) spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD) were used to characterize the biosorbent. The batch adsorption test was used to evaluate the adsorption viability of biosorbents for removing phosphate from aqueous solution. Fe(III)-PGPP was determined to have a pH PZC of 5.40. The experimental data were best explained by the Langmuir isotherm and pseudo-second-order kinetic model. Fe(III)-PGPP had the largest phosphate biosorption capacity of 99.30 mg g –1 at the opti-mum pH of 3.0 and 2.5 hours of contact time. From the results obtained, Fe(III)-PGPP adsorbent can be regarded as an effective and cost-efficient material for the treatment of phosphate-anion-contaminated water.","PeriodicalId":9765,"journal":{"name":"Chemical and Biochemical Engineering Quarterly","volume":"1 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42462364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ivana Martinović, G. Zlatić, Z. Pilić, M. Šušak, F. Falak
{"title":"Antioxidant Capacity and Corrosion Inhibition Efficiency of Sambucus nigra L. Extract","authors":"Ivana Martinović, G. Zlatić, Z. Pilić, M. Šušak, F. Falak","doi":"10.15255/cabeq.2023.2180","DOIUrl":"https://doi.org/10.15255/cabeq.2023.2180","url":null,"abstract":"The cyclic voltammogram recorded in the potential range between 0 V and 800 mV with scan rate of 100 mV s −1 was used to determine the measure of antioxidants content (antioxidant capacity) present in Sambucus nigra L. extract. The antioxidant capacity of the extract was 4.06 mg GAE g −1 fw (mg of gallic acid equivalents per gram of fresh weight of the extract). The corrosion inhibition efficiency of Sambucus nigra L. extract on aluminium, copper, and bronze in 3 % NaCl solution was studied by potentiodynamic polarization and electrochemical impedance spectroscopy. Polarization data showed that extract acted as a mixed-type inhibitor, that the corrosion inhibition process was spontaneous physical adsorption (Δ G ≈ –16 kJ mol –1 ) of the extract molecules on metals surfaces and followed Freundlich isotherm. Impedance spectroscopy studies revealed that increasing the concentration of extract reduced the double-layer capacitance and increased the charge transfer resistance. The highest inhibition efficiencies (Cu: ~ 57 %, CuSn14: ~74 % and Al: ~58 %) were achieved for an extract concentration of 1.0 g L –1 .","PeriodicalId":9765,"journal":{"name":"Chemical and Biochemical Engineering Quarterly","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43584087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}