Scottish Association for Marine Science (SAMS), Scottish Marine Institute, Oban, Argyll, PA37 1QA, UK.
School of Engineering, The University of Edinburgh, Edinburgh, EH9 3FB, UK.
J Environ Manage. 2021 Jul 15;290:112620. doi: 10.1016/j.jenvman.2021.112620. Epub 2021 Apr 22.
Macroalgal biosorption has shown promise for the removal of metal ions from wastewaters, whose presence can pose a threat to the aquatic environment. There is a wealth of literature published on macroalgal biosorption, the common thread being that the biosorbent material was collected from the field, under undefined conditions. These studies offer little insight into the impact of prior cultivation or biomass production practices upon the biosorbent material, its adsorptive physico-chemical properties and its subsequent capacity for metal removal. The present study sought to investigate the influence of changes in macroalgal cultivation, specifically nutrient regime, upon biomass properties and the resultant adsorption performance. The macroalga Cladophora parriaudii was cultivated under six different nutrient regimes; 2:1 and 12:1 N:P molar ratios, with nitrogen supplied either as ammonium (NH), nitrate (NO), or urea (CO(NH)). These nutrient regimes were designed to produce biomass of varying biochemical and cell surface profiles. After cultivation, the biomass was rinsed, dried, biochemically analysed and then used for the removal of four individual metals from solution. Metal removal varied considerably between treatments and across initial metal concentrations, with removal values of 46-85%, 9-80%, 8-71%, and 49-94% achieved for Al, Cu, Mn, and Pb, respectively, with initial metal concentrations varying between 0 and 150 mg L. The observed variation in metal removal can only be attributed to differences in biochemistry and cell surface properties of the biosorbent induced by nutrient regime, as all other variables were constant. This study demonstrates that prior cultivation conditions influence the biochemistry of a biosorbent material, namely macroalgae Cladophora parriaudii, which has an impact upon metal removal. This aspect should be given due consideration for future biosorption research and when reviewing already published literature.
大型藻类的生物吸附已显示出从废水中去除金属离子的潜力，因为这些金属离子的存在会对水生环境构成威胁。大量文献报道了大型藻类的生物吸附，其共同点是生物吸附材料是从野外、在未定义的条件下收集的。这些研究几乎没有深入了解先前的培养或生物质生产实践对生物吸附材料、其吸附物理化学性质及其随后的金属去除能力的影响。本研究旨在调查大型藻类培养条件的变化，特别是营养盐条件，对生物质特性和随后的吸附性能的影响。采用六种不同的营养盐条件（N:P 摩尔比为 2:1 和 12:1），分别用铵（NH）、硝酸盐（NO）或尿素（CO(NH)）作为氮源，培养 Cladophora parriaudii 藻类。这些营养盐条件旨在产生具有不同生化和细胞表面特征的生物质。培养后，将生物质冲洗、干燥、生化分析，然后用于从溶液中去除四种不同的金属。不同处理和初始金属浓度之间的金属去除率差异很大，Al、Cu、Mn 和 Pb 的去除率分别为 46-85%、9-80%、8-71%和 49-94%，初始金属浓度在 0 至 150 mg/L 之间变化。观察到的金属去除率的变化只能归因于营养盐条件引起的生物吸附剂的生物化学和细胞表面特性的差异，因为所有其他变量都是恒定的。本研究表明，先前的培养条件会影响生物吸附材料（即大型藻类 Cladophora parriaudii）的生物化学性质，从而影响金属的去除。在未来的生物吸附研究和审查已经发表的文献时，应该考虑到这一方面。
