Alkaline flocculation of Phaeodactylum tricornutum induced by brucite and calcite.

Bioresour Technol

KU Leuven Kulak, Laboratory Aquatic Biology, Etienne Sabbelaan 53, 8500 Kortrijk, Belgium.

Published: November 2015

Alkaline flocculation holds great potential as a low-cost harvesting method for marine microalgae biomass production. Alkaline flocculation is induced by an increase in pH and is related to precipitation of calcium and magnesium salts. In this study, we used the diatom Phaeodactylum tricornutum as model organism to study alkaline flocculation of marine microalgae cultured in seawater medium. Flocculation started when pH was increased to 10 and flocculation efficiency reached 90% when pH was 10.5, which was consistent with precipitation modeling for brucite or Mg(OH)2. Compared to freshwater species, more magnesium is needed to achieve flocculation (>7.5mM). Zeta potential measurements suggest that brucite precipitation caused flocculation by charge neutralization. When calcium concentration was 12.5mM, flocculation was also observed at a pH of 10. Zeta potential remained negative up to pH 11.5, suggesting that precipitated calcite caused flocculation by a sweeping coagulation mechanism.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.biortech.2015.08.042DOI Listing

Publication Analysis

Top Keywords

alkaline flocculation
16
flocculation
9
phaeodactylum tricornutum
8
marine microalgae
8
zeta potential
8
caused flocculation
8
alkaline
4
flocculation phaeodactylum
4
tricornutum induced
4
induced brucite
4

Similar Publications

Study on the effect of water content on physical properties of bentonite.

PLoS One

January 2025

Lecturer College of Civil and Traffic Engineering, Henan University of Urban Construction, Ping Dingshan, China.

Moisture content profoundly influences the engineering properties of expansive soil, a critical consideration in various geotechnical applications. This study delves into the intricate relationship between water content and the physical properties of bentonite, a key constituent of expansive soil. Through a comprehensive analysis encompassing fundamental physical properties, rheological characteristics, permeability behavior, and microscopic features, we elucidate the complex interplay between water content and bentonite behavior.

View Article and Find Full Text PDF

Prospects of cowpea protein as an alternative and natural emulsifier for food applications: Effect of pH and oil concentration.

Int J Biol Macromol

January 2025

Department of Food Engineering and Technology, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University (UNESP), Street Cristóvão Colombo, 2265, São José do Rio Preto 15054-000, Brazil. Electronic address:

In response to the growing need to expand the knowledge base on novel, more sustainable protein sources, this study investigated the effectiveness of cowpea protein concentrate (CPC) as a natural emulsifying agent, examining the relationships between pH (3-11), oil concentration (2-10 %), and emulsion stability. pH and oil concentration significantly impacted droplet size distribution, with uniformity decreasing in the order of pH 9 > pH 11 > pH 7, which was attributed to droplet coalescence and flocculation. As evidenced by circular dichroism, alkalinity induced a slight increase in the beta-sheet content of CPC, while simultaneously reducing the alpha-helix content.

View Article and Find Full Text PDF

Microplastics, as a novel type of environmental pollutant, have attracted notable attention in environmental research due to their widespread distribution and potential biological toxicity. Drinking water treatment plants play a crucial role in ensuring the safety of the water supply, with a particular focus on the removal efficiency of microplastics in drinking water treatment plants. Different treatment processes in water plants exhibit various removal efficiencies of microplastics and they operate through distinct removal mechanisms.

View Article and Find Full Text PDF

Overcoming deep-dewatering challenges in food waste digestate with polyethylene oxide as an innovative conditioning agent.

Water Res

February 2025

Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Center of Wastewater Resource Reuse, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China. Electronic address:

The effective treatment of food waste digestate is critical for reducing environmental pollution and mitigating carbon emissions, with deep dewatering playing a pivotal role. Conventional dewatering agents such as polyaluminum chloride (PAC) and polyacrylamide (PAM), commonly employed in municipal sludge treatment, exhibit limited efficacy when applied to food waste digestate due to the latter's high salinity and advanced fermentation stages. This study introduces polyethylene oxide (PEO) as a novel conditioning agent and investigates its dewatering performance in comparison to PAC and PAM, elucidating the underlying mechanism.

View Article and Find Full Text PDF

Background: Alkaline-extracted walnut protein isolates (WPI) exhibit limited solubility, which poses challenges for their application in the food industry. The present study investigated the effects of protein-glutaminase (PG) deamidation on the physicochemical characteristics, solubility and emulsifying properties of WPI.

Results: The deamidation process of WPI was monitored by assessing the release of free ammonia and the reduction in solution turbidity.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!