The adsorption of asphaltene on the rock surface and the changes in its wettability are very relevant issues in flow assurance and oil recovery studies, and for carbonate reservoirs, they are even more important. During microbial enhanced oil recovery (MEOR) processes, wettability alteration is considered a crucial mechanism leading to improved oil recovery. Therefore, it is essential to understand the mechanisms of surface wettability changes by bacteria and biosurfactants and find new and reliable methods to prevent asphaltene adsorption. Hence, the main aim of this research was to investigate the effect of a mixture of thiobacillus thiooxidans and thiobacillus ferooxidans microorganisms with an optimum effective temperature of around 30 °C (referred to as mesophilic bacteria), as well as a mixture of two moderate thermophiles Sulfobacillus thermosulfidooxidans for operating temperatures around 50 °C (referred to as moderately thermophilic bacteria) on the adsorption of asphaltene samples isolated from two different crude oils onto main reservoir minerals (i.e., quartz and dolomite). The results indicated that after two weeks of mineral aging in moderate thermophilic bacteria, the adsorption of asphaltene on both minerals increased between 180 and 290%. Fourier-transform infrared spectroscopy (FTIR) analysis for quartz and dolomite samples demonstrated that after aging in bacterial solution, bonds related to the adsorption of bacterial cells and biosurfactant production appear, which are the main factors of change in wettability. Alteration in wettability towards hydrophilicity expands hydrogen bonds on the surface, thus improving asphaltene adsorption due to polar interaction. Asphaltene 1 changed the contact angle of dolomite from 53.85° to 90.51° and asphaltene 2 from 53.85° to 100.41°. However, both strains of bacteria caused a strong water-wetting effect on the dolomite rock samples. The influence of moderate thermophilic bacteria on surface wettability is more significant than that of mesophilic bacteria, which may be caused by the high protein content of these bacteria, which expands hydrogen bonding with the surface. Adsorption of asphaltenes on dolomite rocks previously aged with bacteria showed that the wetted rock samples retained their water-wet state. This study highlights the dual impact of the used microorganisms. On one hand, they significantly reduce contact angles and shift wettability towards a strongly water-wet condition, a crucial positive factor for MEOR. On the other hand, these microorganisms can elevate the adsorption of asphaltenes on reservoir rock minerals, posing a potential challenge in the form of formation damage, particularly in low-permeability reservoirs.

沥青质在岩石表面的吸附及其润湿性的变化是流动保证和采油研究中非常相关的问题，对于碳酸盐岩油藏来说，它们更为重要。在微生物强化采油（MEOR）过程中，润湿性改变被认为是提高采收率的关键机制。因此，有必要了解细菌和生物表面活性剂改变表面润湿性的机制，并找到新的、可靠的方法来防止沥青质吸附。因此，本研究的主要目的是研究最适有效温度为 30 °C 左右的氧化硫硫杆菌和亚铁氧化硫杆菌微生物（称为嗜温菌）的混合物，以及两种中度嗜热菌的混合物的效果。工作温度约为 50 °C 的热硫化氧化硫化杆菌（称为中度嗜热细菌）对从两种不同原油中分离出的沥青质样品吸附到主要储层矿物（即石英和白云石）上的影响。结果表明，矿物在中度嗜热细菌中老化两周后，两种矿物对沥青质的吸附量增加了 180% 至 290%。对石英和白云石样品的傅里叶变换红外光谱（FTIR）分析表明，在细菌溶液中老化后，出现与细菌细胞吸附和生物表面活性剂产生相关的键，这是润湿性变化的主要因素。润湿性向亲水性的改变扩大了表面上的氢键，从而由于极性相互作用而改善了沥青质的吸附。沥青质1将白云石的接触角从53.85°改变为90.51°，沥青质2从53.85°改变为100.41°。然而，这两种细菌菌株都对白云石岩石样品产生了强烈的水润湿作用。中度嗜热细菌对表面润湿性的影响比嗜温细菌更显着，这可能是由于这些细菌的蛋白质含量较高，扩大了与表面的氢键作用所致。先前用细菌老化的白云石岩石上的沥青质吸附表明润湿的岩石样品保持其水润湿状态。这项研究强调了所用微生物的双重影响。一方面，它们显着降低接触角，并将润湿性转变为强水润湿条件，这是 MEOR 的关键积极因素。另一方面，这些微生物可以提高储层岩石矿物上沥青质的吸附，从而以地层损害的形式构成潜在挑战，特别是在低渗透储层中。