Asphaltene deposition remains one of the most severe causes of formation damage in carbonate reservoirs, leading to rapid permeability loss and costly flow assurance problems. To mitigate these effects, a new low-molecular-weight asphaltene inhibitor, denoted as Inh-C, was developed and systematically evaluated under high-temperature and high-salinity conditions representative of carbonate formations. Static bottle tests conducted at a concentration of 300 ppm yielded an inhibition efficiency exceeding 94 %, outperforming commercial benchmarks such as DBSA, PAO-amine, and Nano-NiO by 14–50 %. Spectroscopic analyses (ATR-FTIR) confirmed that the inhibition originates from multi-site adsorption through π–π-cation and hydrogen-bonding interactions between Inh-C functional groups and asphaltene aromatic cores. Complementary dynamic light scattering and zeta potential measurements performed under dynamic shear conditions (1000 s -1 ) demonstrated excellent colloidal stabilization, maintaining a hydrodynamic diameter (D h ) below 80 nm and surface charge magnitude |ζ| greater than 28 mV. Rheological testing further revealed a decrease of >60 % in non-Newtonian viscosity of asphaltene-laden crude, indicating effective disruption of flocculated structures. Coreflood experiments conducted in cleaned carbonate cores (k 0 = 215 ± 18 mD) showed that more than 94 % of the initial permeability (k/k 0 ) was preserved after 500 pore volumes (PV) of post-flush. HPLC-UV analysis of effluent samples confirmed a sustained inhibitor concentration above 100 ppm for over 435 PV, with desorption behavior well described by a Langmuir-type isotherm (half-life = 328 PV; R 2 = 0.99), reflecting strong yet reversible adsorption onto carbonate surfaces. The dual-mode mechanism of Inh-C, comprising macroscopic floc peptization and nanoscale electrosteric repulsion, accounts for its superior performance across static, dynamic, and flowing systems. By delivering prolonged inhibition at reduced dosage, Inh-C establishes a new benchmark for sustainable asphaltene management, significantly extending squeeze lifetime while minimizing chemical consumption and operational costs in carbonate reservoirs.
Golab et al. (Wed,) studied this question.