Efficient removal of Congo red and methylene blue using biochar from Medulla Tetrapanacis modified by potassium carbonate

Biochar (BC) prepared from Medulla Tetrapanacis was recognized as having potential in environmental remediation because of its porous texture, abundant chemical surface groups and mineral composition. In this study, a novel modified biochar (KBC) derived from Medulla Tetrapanacis achieved efficient adsorption of Congo red (CR) and methylene blue (MB). Characterization results suggested that the modification had little effect on the group distribution of KBC, but a dramatic expansion of specific surface area was observed on KBC (1180.45 m2/g) compared to BC (198.51 m2/g). KBC exhibited a maximum sorption of 584.17 mg/g for CR and 318.01 mg/g for MB. Kinetic and isotherm studies revealed sorption of CR and MB by KBC was chemosorption, which occurred on the monolayer surface. The comprehensive analysis also provided the basis for the application of KBC to practical production. These outcomes suggested that KBC may become a new option for the effluent treatment.

Surface modification of cellulose with succinic anhydride in dimethyl sulfoxide using potassium carbonate as a catalyst

Cellulose succinates (CSs) having degrees of substitution (DSs) ranging from 0.78 to 2.77 were successfully obtained by reacting cellulose with succinic anhydride (SA) in dimethyl sulfoxide at room temperature using a small amount of inexpensive solid potassium carbonate as a catalyst. Interestingly, CSs with higher DS values were obtained with a much smaller amount of catalyst than previously reported. Moreover, it is possible to control the DS by tailoring the reaction time and mass ratio of cellulose/SA. The hydroxyl groups at the C-6, C-2, and C-3 positions were the main esterification positions. In this process, most of the raw materials are either incorporated into the product or are recoverable. The E-factor, which reflects the sustainability of a given process, was demonstrated to be reduced by 93% by recovering the raw materials.

Oxidative torrefaction of microalga Nannochloropsis Oceanica activated by potassium carbonate for solid biofuel production

Oxidative torrefaction is a promising way for biomass upgrading and solid biofuel production. Alkali metals are considered to be efficient activators for enhancing biofuel upgrading during the thermal reaction process. Herein, the microalga Nannochloropsis Oceanica is selected as the feedstock for assessing potassium carbonate activated effect on solid biofuel production through oxidative torrefaction. The potential of potassium carbonate on microalgal biofuel properties upgrading is deeply explored. SEM observation and BET analysis show that torrefied microalgae can be transformed from a spherical structure with wrinkles to smaller particles with larger surface areas and higher total pore volumes, implying that potassium carbonate is a promising porogen. Moreover, potassium carbonate can significantly change the DTG curve at the temperatures of 250 °C and 300 °C from one peak to two peaks, inferring that the activated effect of potassium carbonate occurs on the torrefied microalgae. ¹³C NMR analysis reveals that the microalgal components significantly change as the torrefaction severity increases, with the decomposition of carbohydrate and protein components. When the potassium carbonate ratio increases from 0:1 to 1:1, the graphitization degree increase from 3.065 to 1.262, along with the increase in the HHV of solid biofuel from 25.024 MJ kg^-1 to 31.890 MJ kg^-1. In total, this study has comprehensively revealed the activated effect of potassium carbonate on improving the properties of microalgal solid biofuel.

Microalgal feedstock for the production of omega-3 fatty acid ethyl esters and ɛ-polylysine

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Microalgal omega-3 fatty acids can be an alternative for fish based omega-3 fatty acids.

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Potassium carbonate is the efficient catalyst for the ethyl ester production.

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ɛ-polylysine can be produced from the spent biomass after transesterification.

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Co-production of two products could be the promising bio-refinery approach.

Microalgal omega-3 fatty acids are considered as an efficient alternative for fish-based omega-3 fatty acids. Ethyl esters derived from omega-3 fatty acids are being considered as the drug for hypertriglyceridemia. In this study, omega-3 fatty acids rich Chlorella sp. was utilized for the transesterification for the ethyl ester production using a potassium carbonate alkaline catalyst. At the optimized conditions of transesterification, 86.2% ethyl ester yield was achieved with solvent to algae ratio (20 mL/g), water addition (45 %), catalyst (4 %), temperature (75°C), and reaction time (60 min). Additionally, the acid-hydrolysed spent biomass was used for the production of ɛ-polylysine by fermentation using Streptomyces sp. as fermentative organism. The maximum yield of 1.78 g/L was achieved after 90 h fermentation. This study established a biorefinery approach where two highly valuable compounds could be produced from the Chlorella sp. by transesterification followed by fermentation.

A gas-free electrodialytic pH modifier for ion chromatography

We for the first time describe a gas-free electrodialytic pH modifier deployed at the pump outlet side to manipulate carbonate eluent used for ion chromatography (IC). It is in sandwich configured, in which the central eluent channel is spatially isolated from two outer regenerant chambers by a stacked cation exchange membranes (sCEM) and a bipolar membrane (BPM) plus a stacked anion exchange membranes (sAEM) (BPM-sAEM), the cation exchange side of BPM is facing the central channel (the cathode direction). One electrode is put in each regenerant chamber and the sCEM side is cathode with respect to the anode of BPM-sAEM side. When a potassium carbonate eluent is pumped into the central channel and a DC current is applied, a controlled amount of potassium ions will be removed by migrating across sCEM into cathodic chamber. Meanwhile, hydronium ions generated from enhanced water splitting at the intermediate layer of BPM will electromigrate into central channel to form bicarbonate. By controlling the current, the potassium carbonate eluent can be manipulated to obtain a mixed eluent with different ratio of carbonate and bicarbonate. At least 10 mM K₂CO₃ eluent can be online changed modified into 10 mM KHCO₃ with near-ideal Faradaic efficiency (∼92%). The device demonstrated good reproducibility, as indicated by retention time of relative standard deviation (RSD) < 0.43% and the peak area of RSD <0.93%.

Co-valorization of delayed petroleum coke - palm kernel shell for activated carbon production

In this study, a binary mixture of petroleum coke and palm kernel shell had been investigated as potential starting materials for activated carbon production. Single-stage potassium carbonate (K₂CO₃) activation under nitrogen (N₂) atmosphere was adopted in this research study. Effect of several operating parameters that included the impregnation ratio (1-3 wt./wt.), activation temperature (600-800 °C), and dwell time (1-2 hrs) were analyzed by using the Box-Behnken experimental design. Influence of these parameters towards activated carbon yield (Y₁) and carbon dioxide (CO₂) adsorption capacity at an atmospheric condition (Y₂) were investigated. The optimum conditions for the activated carbon production were attained at impregnation ratio of 1.75:1, activation temperature of 680 °C, and dwell time of 1 h, with its corresponding Y₁ and Y₂ is 56.2 wt.% and 2.3991 mmol/g, respectively. Physicochemical properties of the pristine materials and synthesized activated carbon at the optimum conditions were analyzed in terms of their decomposition behavior, surface morphology, elemental composition, and textural characteristics. The study revealed that the blend of petroleum coke and palm kernel shell can be effectively used as the activated carbon precursors, and the experimental findings demonstrated comparable CO₂ adsorption performance with commercial activated carbon as well as that in literatures.

Dechlorination of polyvinyl chloride electric wires by hydrothermal treatment using K2CO3 in subcritical water

Polyvinyl chloride (PVC) waste generation has significantly increased in recent years and their disposal is considered a major environmental concern. Removal techniques of chlorine from PVC waste are being studied to minimize a negative environmental impact. In this work, the use of K₂CO₃ as an alkaline additive to improve the dechlorination efficiency (DE) in the hydrothermal degradation of PVC wires was studied. Different experiments were carried out varying both temperature (175, 200, 225, 235 and 250 °C) and K₂CO₃ concentration (0.025, 0.050 and 0.125 M), using a solid/liquid ratio of 1:5 in order to determine the evolution of the dechlorination efficiency with time. About 4.66, 21.1, 24.4, 45.7 and 92.6 wt% of chlorine in PVC wire was removed during hydrothermal dechlorination (HTD) with an additive/chlorine ratio of 1:25 (K₂CO₃ solution of 0.050 M) at 175, 200, 225, 235 and 250 °C, respectively. Optimal additive/chlorine ratio decreased to 1:50 (K₂CO₃ solution of 0.025 M) at 250 °C, obtaining a dechlorination degree of 99.1% after 4 h without the need of metallic catalysts. Concerning the solid phase behavior during dechlorination, a linear correlation between the DE reached and the weight loss of PVC was found.

Potassium phosphate and potassium carbonate administration by feed or drinking water improved broiler performance, bone strength, digestive phosphatase activity and phosphorus digestibility under induced heat stress conditions

Potassium phosphate (K₂HPO₄) and potassium carbonate (K₂CO₃) administration by feed or water were evaluated on broiler performance, bone strength, alkaline phosphatase activity (ALP), and phosphorus digestibility under heat stress and high chloride condition. Experimental groups include control; 15 cc/kg K₂HPO₄; 30 cc/kg K₂HPO₄; 15 cc/l K₂HPO₄; and 3.7 g/kg K₂CO₃. Body weight (BW), feed and water consumption, plasma potassium, phosphorus, and calcium concentration along with plasma and digestive ALP and intestinal digesta pH were measured during the trial. Tibia ash, calcium and phosphorus content, and breaking strength were measured on days 21 and 42 and phosphorus digestibility on day 36 of age. As a result of this, study feed and water consumption was increased by supplementation of the feed or water with K₂HPO₄ (P ≤ 0.001). K₂HPO₄ increased body weight at 42 days of age (P ≤ 0.001). Tibia ash and phosphorus content was increased by K₂HPO₄ supplementation (P ≤ 0.004; P ≤ 0.003). K₂CO₃ did increased tibia ash but not changed tibia phosphorus content significantly. Tibia shear force, shear energy, extension, and length were improved by K₂HPO₄ administration at 42 days of age (P ≤ 0.001). Administration of either feed or water with K₂HPO₄ increased plasma potassium, phosphorus, and calcium concentration at 21 days of age, whereas K₂CO₃ reduced plasma potassium at 21 days of age (P ≤ 0.05). Plasma ALP reduced by addition of 15 cc K₂HPO₄ and K₂CO₃ to diets at 42 days of age, whereas digestive ALP was increased by inclusion of K₂HPO₄ and not by K₂CO₃. Supplementation of either feed or water with K₂HPO₄ increased phosphorus digestibility, whereas K₂CO₃ reduced phosphorus digestibility (P ≤ 0.003). Jejunum and ileum pH was reduced by K₂HPO₄ or by K₂CO₃ at 21 and 42 days of age (P ≤ 0.006; (P ≤ 0.05). Over all, results of current study revealed that K₂HPO₄ can be a suitable potassium salt choice instead of KCL in hot weather conditions especially when the water or diet contains high levels of chloride.

Potassium carbonate improves fresh pork quality characteristics

Meat enhancement strategies like sodium tripolyphosphate (STP) are used to improve fresh meat quality attributes like color, water-holding capacity, and tenderness. However, alternatives are necessary because of reduced consumer acceptance of STP. One alternative is potassium carbonate (K₂CO₃). A study was conducted to evaluate K₂CO₃'s impact on fresh, boneless, center-cut pork loins enhanced with one of five treatments: a negative control, positive control (0.3% STP), and three concentrations of K₂CO₃ (0.1, 0.3, and 0.5%). Loins were cut into chops, stored under simulated retail display, and analyzed for color (L*, a*, b*), pH, cook loss, and tenderness. For each quality characteristic measured, the 0.3% and 0.5% K₂CO₃ maintained redness (a*), decreased yellowness (b*), reduced cooking loss, and maintained tenderness compared to STP. SDS-PAGE analysis further determined that both K₂CO₃ and STP extracted myosin heavy chain. Combined, these data suggest that K₂CO₃ may function as an alternative to STP in the fresh pork industry provided microbial safety and shelf-life are appropriately controlled.

Reduction of the frequency of recurrent diverticulitis episodes under treatment with the integrative medicine therapies Carpellum Mali comp. and Kalium aceticum comp.-A case report

BACKGROUND

Colonic diverticula develop in at least 60% of elderly patients. Less than 25% of these develop diverticulitis. Recurrent episodes are experienced by about 13% of the symptomatic patients. The effect on prevention of recurrent diverticulitis of currently used therapies is controversial. Surgical colon resection is used in some patients in emergency or to prevent future episodes and complications. Carpellum Mali comp. (Juglans regia, Testa; Pirus malus, Carpellum) and Kalium aceticum comp. (Kalium carbonicum, Acetum vini destillatum, Antimonit, Crocus sativus, Spiritus e vino, Corallium rubrum) - preparations of Integrative Anthroposophic Medicine - have been used for at least 60 years to improve chronic abdominal pain and to treat obstipation, irritable bowel syndrome and colitis.

CASE PRESENTATION

A 72-year-old retired physician presented in 2013 with a 7-year history of recurrent diverticulitis. During the first 6 years, three to four episodes each year required antibiotic therapy. In 2013 the episodes became more frequent, occurring approximately every 2 months. The patient was concerned about risks from repeated antibiotic treatment and the potential need for surgery. Oral Carpellum Mali comp. and subcutaneous Kalium aceticum comp. treatments were added to the therapy in March. The patient experienced improvement over 4 months without any symptoms. In the following 28 months she had 4 minor diverticulitis episodes, followed by 11-months without any flares; she reported no side effects in the 41-month follow-up period.

CONCLUSION

Carpellum Mali comp. and Kalium aceticum comp. seem to have been helpful in the case presented here. Experiences with theses remedies in recurrent diverticulitis should be collected to determine whether it would be meaningful to carry out further investigations.

KRS 101 using potassium carbonate

A new in-situ transesterification method was developed for wet biomass: K₂CO₃ was used as an alkaline catalyst and, Aurantiochytrium sp. KRS 101 as oleaginous DHA-producing microalgae. It was found that the presence of water greatly impaired the overall efficiency even with the powerful catalyst that had worked surpassingly well with dry biomass, and thus a mechanical aid like ultrasonication was needed to make advantage of full potential of the alkaline catalyst. The total fatty acid ethyl ester (FAEE) recovery yield of 94.6% was achieved with sonication at 100 g/L of biomass (40% moisture), 3% of K₂CO₃, 70 °C and 30 min. All these suggest that the ultrasound assisted in-situ transesterification can offer a feasible means for FAEE recovery and it was so by way of overcoming the physical limitation of mass transfer caused the presence of water and providing effective contacts between reactants.

Adsorption of ciprofloxacin and norfloxacin from aqueous solution onto granular activated carbon in fixed bed column

Carbonization of Phoenix dactylifera L stones followed by microwave K₂CO₃ activation was adopted for preparation of granular activated carbon (KAC). High yield and favorable pore characteristics in terms of surface area and pore volume were reported for KAC as follows: 44%, 852m²/g, and 0.671cm³/g, respectively. The application of KAC as adsorbent for attraction of ciprofloxacin (CIP) and norfloxacin (NOR) was investigated using fixed bed systems. The effect of flow rate (0.5-1.5ml/min), bed height (15-25cm), and initial drug concentration (75-225mg/l) on the behavior of breakthrough curves was explained. The fixed bed analysis showed the better correlation of breakthrough data by both Thomas and Yoon-Nelson models. Inlet drug concentration was of greatest effect on breakthrough data compared to other fixed bed variables. Experimental and calculated breakthrough data were obtained for CIP and NOR adsorption on KAC, thus being important for design of fixed bed column.

KRS 101 using potassium carbonate

The aims of this work were to evaluate K2CO3 as a potent alkaline catalyst for in situ transesterification of Aurantiochytrium sp. KRS 101, one step process in which oil extraction and conversion take place together. This K2CO3-based in situ transesterification was optimized in terms of recovery yield of fatty acid methyl esters (FAMEs) by way of varying biomass concentration, reaction temperature, reaction time, and catalyst concentration. The optimal condition was achieved at 50g/L of biomass concentration and 1% of K2CO3 in the methanol, 25°C of reaction temperature, and 5min of reaction time, resulting in the FAME recovery yield over 90%. It was found that K2CO3 performed better than any other tested catalysts including acids, supporting the notion that K2CO3 is a promising catalyst, especially for in situ transesterification.