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Optimization of (2E)-3,7-dimethyl-2,6-octadien-l-ol (geraniol) transformation process parameters using Response Surface Method (RSM)

Fajdek-Bieda Anna, Wróblewska Agnieszka

Polish Journal of Chemical Technology

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2024

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Vol. 26, nr 1

24--38

EN

This paper presents the results of studies on the transformation of geraniol (GA) in the presence of the natural mineral bentonite. The paper determines the influence of temperature, catalyst content, and reaction time on the course of the process. In order to determine the most favorable process conditions, the catalytic tests were carried out without solvent and under atmospheric pressure. Three functions were chosen to determine the most favorable process conditions: GA conversion and the selectivities of the main products: linalool – LO and beta-pinene – BP. In addition, the paper optimize GA transformation process based on response surface methodology (RSM). The impact of the most relevant process indicators was presented. For all factors of the method, their effects on all primary parameters were determined in the form of second-degree polynomials, and such process conditions were determined to achieve their maximum.

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Isolation of citronellal and geraniol from citronella (Cymbopogon winterianus) oil by vacuum fractional distillation: Effect of operating conditions on the separation

Le Minh-Trung, Vu Duc-Phuong, Nguyen Thanh Ngoc, Le Xuan-Tien

Polish Journal of Chemical Technology

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2023

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Vol. 25, nr 4

67--80

EN

This study used fractional distillation to separate citronellal and geraniol from citronella (Cymbopogon winterianus) essential oil to improve their market value. The one-factor-at-a-time methodology investigated operating parameters’ optimum conditions and effects, including system pressure, packing types, and column height. All investigations were evaluated based on their main fraction’s citronellal and geraniol content and recovery. Regarding the effect of the variables, a higher system pressure improved the separation while increasing the temperature range of each fraction and distillation time. The packing types would also improve the separation by providing a large surface area. Finally, the column height also positively impacted the separation. In the optimum citronella oil fractionation, citronellal content experienced a 2.5-fold increase, from 37.68% to 94.33%. Geraniol purity reached 40.61% from an initial content of 17.33% in the raw CW oil. The distillation could recover up to 90.00% of citronellal and 68.18% of geraniol.

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Green method of conversion of geraniol to value-added products in the presence of selected minerals

Fajdek-Bieda Anna, Wróblewska Agnieszka, Perec Andrzej, Miądlicki Piotr

Polish Journal of Chemical Technology

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2023

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Vol. 25, nr 1

47--60

EN

The study presents the results of research on the process of geraniol (GA) transformation in the presence of natural minerals: montmorillonite, mironekuton, halloysite and also in the presence of halloysite modified with 0.1 M water solution of H2SO4. To obtain information on the structure of the used catalysts, instrumental studies were performed (SEM, XRD, FT-IR, XRF, BET). The second part of the research consisted in examining the influence of individual parameters (temperature, catalyst content, and reaction time) on the course of GA transformation process. The syntheses were carried out without the application of solvent and under atmospheric pressure. To determine the most beneficial process conditions, two functions were selected: GA conversion and selectivity of GA. The proposed method of GA transformation on such minerals: montmorillonite, mironekuton, halloysite, has not been described in the literature so far.

4

Evaluation of chemical composition of essential oils derived from different Pelargonium species leaves

Szutt Adriana, Dołhańczuk-Śródka Agnieszka, Sporek Monika

Ecological Chemistry and Engineering. S

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2019

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Vol. 26, nr 4

807--816

EN

Plants have been used for their aromatic and medicinal purposes for centuries. The genus Pelargonium contains about 250-280 species and cultivated around the world for the production of essential oils and absolutes. Pelargonium species are remarkable for their odour diversity, from fresh, lemon and minty scent, through floral, rose, fruity up to spicy and camphoreous smell as well as many health beneficial properties, that is why their essential oils are widely used in perfume, cosmetic, food and pharmaceutical industries. The aim of this study was to determine variability in populations of Pelargonium genus by evaluating their differences in quantitative and qualitative essential oils compositions. This study determined that of all the examined essential oil, the one of P. graveolens indoor cultivar has the closest C:G ratio (1.16) which makes it a very valuable product. In comparison with available literature, beside the geographical region of plant growth, all essential oils from P. graveolens contain a diverse range of compounds, nevertheless, in every single one, geraniol and citronellol are present in the most significant fraction of the total oil. The examined P. roseum essential oil was characterized by the highest level of citronellol (44.62 % of total oil), but it can be due to the chemical reactions (conversion geraniol into citronellol) occurring in stored product.

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Otrzymywanie środków zapachowych na drodze utleniania terpenów z wykorzystaniem zasad zrównoważonej chemii

Feliczak-Guzik A., Nowak I.

Wiadomości Chemiczne

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2010

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[Z] 64, 9-10

787-808

EN

The review presents some of the key catalytic transformations of a major monoterpene feedstocks. Green chemistry is a philosophy of chemical research and engineering that encourages design of products and processes that reduce the use and generation of dangerous substances. Thus one of the challenging goals of organic synthesis and catalysis is to develop stable heterogeneous catalysts capable to operate at ambient conditions perform selectivity as high as that of homogeneous catalysts. Terpenes represent one of the largest and most diverse classes of compounds, with over 55,000 members isolated to date. Their further oxidation and rearrangement results in an almost endless number of conceivable structures. Monoterpenes are key ingredients in the flavor and fragrance industry, with α- and β-pinene (obtained from turpentine) being some of the most important. The review focuses on the terpenes: pinene, limonene, and the interconversion of the monooxygenates: geraniol, nerol, citronellol, and citronellal. The major areas covered are catalytic hydrogenation/hydrogenolysis, dehydrogenation, rearrangement/ isomerization. However, this review focuses mainly on the oxidation of pinene and geraniol on heterogeneous catalysts.