Fossil fuels are the significant contributor to the world energy demand [
1,
2,
3,
4,
5].It is reported that carbonate reservoirs rock formations exhibits massive volume of about 60% of all the global reserves. Hence, carbonate reservoirs are considered to be the crucial targets to fulfill the present day energy needs [
6,
7]. Exploitation and development of carbonate reservoirs is challenging due to heterogeneity and its complex multi-modal pore structures[
8,
9].Generally, low hydrocarbon recovery from carbonate reservoirs is mainly due to its nature of the mixed to oil-wet characteristics[
10,
11,
12]. For instance, oil-wet carbonate rocks shows higher residual oil saturations due to larger bonding of oil and reservoir rock[
13] and higher interfacial tensions (IFT) [
14]. Thus, this requires considerable attention by which wettability can be altered and to recover the trapped oil amounts. Most of these reservoirs are water-wet; thus, the residual trapping of oil is larger at the in-situ conditions and even at core scale [
15,
16]. Many studies have described the rock wetting phenomena in which higher amounts of residual oil are trapped within subsurface formations mainly due to the strong water-wet conditions [
15,
16,
17]. Though, the oil recovery from carbonate reservoirs via secondary recovery methods is ineffective. Generally, the oil is produced from fractures via secondary recovery flooding operations; however, the water is not absorbed into the matrix of the carbonate rocks due to its inherited oil-wet behavior [
18]. Thus, the oil remains trapped in carbonate reservoir rocks and the overall recovery by secondary recovery processes in such reservoirs achieved is up to 10-30% [
19].Basically, the displacement efficiencies of carbonate reservoirs are mainly affected by various parameters, such as fluid viscosities, IFT, rock pore morphology, and Wettability of the rock[
20]. Among all above mentioned parameters wettability is one of the more desirable to evaluate the flow behavior such rocks. In addition, the reservoir dynamic properties are mainly affected by wettability which in turn is affected by subsurface reservoir rock mineral composition and formation brines chemistry[
21,
22]. Therefore, the wettability is considered to be one of the most essential rock properties to influence the fluid flow in subsurface reservoir rocks [
23,
24,
25]. Obviously, the definition of wettability is very simple but it is very complex to underhand the expression at reservoir scale or even within core plug at lab scale due to the fact that rock exhibit complex pore morphologies, rock heterogeneities and divergent mineral constituents[
24]. Therefore, several methods have been introduced to modify the wettability of such rocks and to enhance the trapped oil recovery. Recently, an industrial waste i.e. the methylene blue dye and organic pollutant is in use to alter the wetting behavior of these carbonates has multiple advantages. Firstly, this mitigates the disposal of industrial waste-water (hazardous substances) into environment and may contaminate the water table. Secondly, the use of MB modifies the rock wettability and enhances the oil recovery and hydrogen geo-storage capacity[
7]. In addition, recently the use of nano materials by dispersing with distilled water as a base fluid to formulate the nanofluids has gained considerable importance in improving the oil recovery [
26,
27,
28,
29]. Generally the nanofluids are formed by dispersing the desired quantity of nanoparticles into the base fluid. Over the decades, various nano materials have been introduced for improved oil recovery including the TiO2 [
30] SiO2 [
31,
32,
33], Zinc oxide (ZnO)[
34]and the graphene [
35]. Thus, nanofluids have appeared as a prominent materials to recover the trapped oil by altering the oil-water IFT, changing the effluents viscosity and to increase the oil mobility[
36], to alter the rock wettability[
37]. Substantial oil and gas resources are present in the Central and lower Indus Basin, Pakistan. Numerous fields are the globe is currently produces from carbonate reservoirs which can be benefited. Existing production data shows that conventional methods of recovery are inefficient and challenging due to number of reasons i.e. diversified rock composition, complex pore network and fractured rocks. Thus, the present study’s key target is to improve the residual oil productivity of particularly from carbonate reservoir rocks through application of nano-fluids and MB treatments. By the applications of such treatments to Sui main limestone rocks, the oil recovery would be improved through wettability modifications[
7]. The following paper aims to investigate systematically, the impact of methyl blue, alumina nanoparticles over wide range of experimental conditions on wettability alteration as well as improving the enhanced recovery.